Document 3N95JB0KX314wX97zQa0o1D6a

% ' 'A. -1 VOLUME FOUR-1975 CASE HISTORIES OF ACCIDENTS IN THE CHEMICAL INDUSTRY i i !I \ f rHzDa Ml c.< MANUFACTURING CHEMISTS ASSOCIATION TS2S CONNECTICUT AVENUE, N.W. - WASHINGTON, D.C. 20009 i i CMA. 0487X3 I '3 <r 3 7 0 ft 1 * S i 4 c t'. I / Ifc cif <1, ;i C A L 1 CMA 048714 I*--* CASE HISTORIES OF ACCIDENTS IN THE CHEMICAL INDUSTRY Published as an activity of the SAFETY AND FIRE PROTECTION COMMITTEE of the MANUFACTURING CHEMISTS ASSOCIATION VOLUME FOUR Copyright 1975 by the Manufacturing Chemists' Association, Inc, CMA 04B715 APRIL 1975 LIBRARY MANUFACTURING CHEMISTS' ASSN 1825 CONNECTICUT AVE.. N. W. WASHINGTON. D. G. 20008 tar FOREWORD Since 1951, member companies of the Manufacturing Chemists Association have voluntarily cooperated in the Association's safety program by submitting case histories of accidents or near-accidents occurring in chemical plants. Behind this unique joint endeavor is the compelling concern of industry managements for the welfare of employees. It reflects an open resolve by leaders of the industry that mistakes or omissions of today will not be repeated tomorrow. Accident case histories are written by plant foremen, operating personnel, or other local company representatives. They are edited only as necessary to preserve a standard format and are published as an activity of MCA's Safety and Fire Protection Committee. Since they are submitted on a confidential basis the company name is not divulged. Industry reception of this monthly publication has been encouraging. Many companies engaged in operations similar to those described in particular case histories have adopted the preventive measures recommended, A number of companies purchase multiple copies of the monthly issue for distribution to plants, for study at safety meetings. This edition, Volume Four, is a compilation of accident case histories published in the bulletin during the 1970-74 period. Volume Three contains accident case histories Nos. 1098 through 1623, published 1966-69. Volume Two--1966 contains accident case histories Nos. 597 through 1097, published 1960-65. Volume One--1960 contains acci dent case histories selected from those published 1951-1959. MCA's Safety and Fire Protection Committee is grateful to companies which have cooperated in the accident case history program. It looks for increasing cooperation. Those who find this volume helpful are asked to contribute to future issues by submitting to MCA case histories of accidents or near-accidents should they occur. Please address correspon dence to The Editor-Secretary, Safety and Fire Protection Committee, Manufacturing Chemists Association, 1825 Connecticut Ave., N.W., Washington, D.C. 20009. The case histones contained in this volume have been submitted in good faith by the chemical companies which experienced the accident or incident described. No warranty, guarantee, or representation is made by the Manufacturing Chemists Association as to the correctness or sufficiency of any information, statement of accident cause, or recommenda tions for preventive measures contained herein or that other or additional measures may not be required. CASE HISTORIES of Accidents in the Chemical Industry CASE HISTORY NO. 1624 Ortho-nitroaniline Explosion Description: An ortho-nitroaniline (ON A) reaction went out of control resulting in overpressure and consequent violent rupture of the reactor. Four men sustained disabling in juries. The building was destroyed and damage to the adja cent area was widespread. ONA is produced by reacting ortho-nitrochlorobenzine (ONCB) with aqueous ammonia. ONCB is pumped from a storage tank to a volumetric measuring tank for charging to the reactor. The reactor was being charged with OCNB at 7; 15 p. m. When the sight glass in the charge line failed to run empty in the usual time, the operator realized he had forgottoi to shut down the pump from the ONCB supply tank to the ^suring tank. An interlock, normally used to prevent this ^ffor, was not in service due to the temporary use of a tank car and temporary feed pump while the regular ONCB storage tank ahd pump were out of service for repair. Operators had been cautioned to use extra care in charging while the inter lock was out of service. Assuming a probable overcharge of ONCB, the operator intentionally undercharged the ammonia to avoid overload ing the reactor. He did not report the batch abnormality to his supervision. After heat was applied to raise the batch to the reaction temperature, difficulty was experienced in controlling temp erature and pressure by application of cooling water or by release of ammonia vapor to an absorber. By 12:18 a.m., pressure was rising rapidly in spite of an open manual vent line, and the rupture disc and relief valve opened. The operators ran for the exits, but the reactor exploded in a matter of seconds. Cause: Investigation revealed a number of factors contribut ing to the accident. 1. The cooling system, adequate for original design con ditions, was marginal at increased production rates and inadequate to handle the heat load in the abnormal batch. 2. Absence of the interlock, coupled with operator error, resulted in overcharge of ONCB and abnormal operat ing conditions. . The 650-pound rupture disc relief valve system, origi ns nally installed immediately on the reactor, had at some time in the past been relocated to a point several feet downstream in the vent line system. The disc origi nally specified for 660 lbs. at high temperature had a much higher bursting pressure at the near-ambient temperature under which it was actually operating. At the temperatures equivalent to the actual relieving pressure in the system, the reaction rates far exceeded the combined capacity of the cooling system and the venting system. Temperatures and pressures continued to rise rapidly overpressuring the vessel to its bursting point. Preventive Measures: In the new ONA installation, added precautions will be taken in the form of: 1. More adequate interlocks on raw material charge sys tem. 2. Dual independent temperature and pressure control and alarm systems. 3. More adequate emergency relief system with pressure bleed and gauge protection between disc and backup valve. 4. Secondary emergency relief line with higher pressure disc alone and no back-up valve. 5. Outdoor installation of pressure vessels. CASE HISTORY NO. 1625 Sulfuric Acid Burns Description: Four carpenters were erecting a scaffold around a column in an acid area to facilitate the removal of an overhead vapor line. The job was located in a sulfuric acid area. The carpenters were completing the first level of the scaffold when a 2" line in the area failed. One of the carpenters was severely burned with 90% sulfuric acid, suf fering second and third degree acid bums over 40% of his body. Cause: 1. The carpenters were working in an operating area without adequate protective equipment. 2. Thin walls of the sulfuric acid lines, due to internal corrosion, contributed to failure of brittle cast iron. Preventive Measures: 1. Positive indoctrination will be given to unassigned maintenance personnel by maintenance supervision prior to working in a sulfuric acid restricted area or on sulfuric acid equipment. 2. Maintenance personnel will be instructed in and will adhere to the Sulfuric Acid Safety Standard, which will be reviewed once each year. 3- - CtiK 048717 3. The thickness and general condition of the sulfuric acid pipe system will be investigated routinely. Pipe showing evidence of excessive thinning will be re moved. Cast iron pipe will be removed as soon as possible. 4. Sulfuric acid restricted areas will be examined and their scope revised as necessary to reduce accidental exposure to personnel in adjacent areas. 5. The sulfuric acid systems in use in other areas will be investigated. Long Range Preventive Measures: 1. Ladders and operating platforms will be installed on existing and future sulfuric acid towers as required. 2. A continuation of a search for better piping materials for sulfuric acid will be made. Improved routing and segregation will be considered for piping outside restricted areas. 3. Piping and equipment within the restricted areas will be examined and revised with particular attention given to the following areas; (a) Remote operation of pumps and valves where practical, (b) Improved support and layout. (c) Improved methods for draining. EDITOR'S COMMENT: A correspondent writes that the 2" line failure was apparently caused by a general thinning of the pipe due to uniform corrosion -- a failure typical of spun cast iron pipe which usually has a uniform wall thickness and usually fails suddenly in the manner of an egg shell fracture. Failure, he says, can be controlled by 1/16 to 1/8" holes drilled to a depth of about 1/3 the wall thickness at strategic points where high velocity may help to cause failure or at selected points on a straight run of case iron pipe. These points will be the first to fail and will give an acid drip indicating a general thinning of the pipe. The drill holes should be so located to minimize exposure of personnel. CASE HISTORY NO. 1626 Fire Caused by 35% Hydrogen Peroxide Description and Causes: Forty 300# drums of 35% hydro gen peroxide were stored in the warehouse on wooden pal lets, five drums to a pallet, tiered four pallets high. One drum on the top pallet developed a leak although this was not discovered until the pallet was moved for shipment. When the pallet was lowered to the floor in front of the shipping door a small area, about 4" diameter, of a pallet board burst into flame. The lift-truck operator attempted, unsuccessfully, to extinguish the fire using two 2 Vi lb. dry chemical extinguishers, one from the truck he was operating, one from another truck. He then used a nearby standpipe fire hose, by which time the fire had grown to about 12" in diameter, and the fire was extinguished. That considerable heat of decomposition had built up in the saturated area is suggested by the fact that water had to be applied several times over a period of about 3-4 minutes (sic) before the fire was finally extinguished. Preventive Measures: 1. More frequent inspections to detect possible "leakers" and as far as practicable avoid tiering of palletized drums of peroxide to facilitate such inspec tion. 2. Seriously reconsider the use of metal pallets pre viously ruled out on account of much higher cost and greater possibility of drums sliding off the metal surface when being transported. 3. Keep stock to the minimum necessary to service cur rent sales. 4. Segregate peroxide stock from combustible stock to avoid the possibility of the latter coming in contact with possible leakage. 5. Give regular training to employees in use of extin guishers, emphasizing what type should be used, e.g., water on fire involving H2O2. CASE HISTORY NO. 1627 Employee Overcome by Benzene Vapors Description: An employee was overcome while cleaning scale from the interior of a tank car that had been in benzene service. The car had been boiled out. Flame and oxygen tests had been made and a check made for odor. All tests were satisfactory. Cleaning proceeded for about two hours with a man inside of the car hosing and pushing sludge out of the bottom outlet, a safety man on top of the car and a man rodding the bottom outlet from the outside. Sludge coming from the bottom outlet was checked for odor and only a slight trace detected. Cleaning was stopped for about an hour and a half to permit a car drill. A half hour after cleaning was resumed, the employee lost consciousness. Cause: Benzene had apparently been trapped in the sludge and was released as it was removed. The three men who had taken turns working in the car at no time were aware of a strong enough smell of benzene to alert them to any danger. Preventive Measures: To prevent a recurrence of this type of accident, the following will be done: 1. Ventilation will be provided in accordance with the requirements set forth in MCA Safety Guide SG-10, "Entering Tanks and Other Enclosed Spaces." 2. An engineering study has been initiated to determine if an improved method for cleaning tank cars can be developed. Emphasis will be placed on eliminating the need for men entering the cars. 3. A Job Safety Analysis will be prepared on tank car cleaning. CASE HISTORY NO. 1628 Fell Through Asbestos Roof Description: An employee was fatally injured when he fell through a corrugated asbestos roof approximately 45 feet. Two men had been assigned to dean up granular coal which CMA 048718 had spilled from a belt conveyor onto a valley in the roof " a production building. They shoveled most of the spillage ay in the morning and after lunch decided to hose down the little coal that remained. During this operation a 2 ft. square section of the roof gave way where one of the two workers was standing. The other with the hose was 25 ft. away but he saw his coworker fall with arms extended above his head. The roof was about 20 years old and had been patched with tar in a number of places, Cuu.se: This tragic accident clearly demonstrates that corru gated asbestos roofs even when new may not be sufficiently strong enough to safely support a man. Prevenrive Mensures: 1. Permanent or temporary scaffolding or ladders are needed to safely work on a roof of this type. 2. The International Occupational Safety and Health Information Center in Geneva, Switzerland reported in February 1969 that the risks involved in working on corrugated asbestos roofs are generally underes timated. The report recommends the installation of wire mesh (about 12-gauge, 4" squares) before the asbestos roofing is applied as a permanent safety measure. The wire mesh is reported to be cheaper than using life nets or building adequate scaffolds and walks to make the roof safe. CASE HISTORY NO. 1630 Molten Wax Spill Description: A tank car of wax had been heated for unload ing into storage. A mechanic was removing the bottom unloading cap, with the intent of connecting the unloading line prior to opening the outlet valve. When the unloading cap was disconnected, a stream of molten wax began drain ing from the tank car. Approximately 8500 gals, of wax was lost before the valve could be closed. Cause: When the mechanic checked the outlet valve, it appeared to be closed. He attempted to turn it and it would not turn. It was discovered later that the valve was jammed partially open and apparently the T/C was loaded with the valve in this condition. Preventive Measures: 1. Explore and implement use of external valve assembly to be installed prior to heating wax to molten state. 2. Determine that tank car valve will travel full range from open to closed position prior to removing unload ing cap. CASE HISTORY NO. 1631 ^ CASE HISTORY NO. 1629 Wne Fatality -- Unloading Tank Car of Liquid Sulfur Description: Two tank cars had been shunted inside the unloading shed. The serviceman climbed onto the platform to loosen the bolts of the tank covers. He had done this on one car and he was found lying unconscious on the platform of the s-'-ond one. He was immediately taken into hospital where the death was certified a few minutes after his arrival. According to the doctor the death could have occurred some 40 minutes before. Pipe Blockage Description: A fitter's mate sustained disabling chemical bums while attempting to open a blocked bottom outlet in a production vessel. He was assisting the shift fitter in removing the 3 " NB crosspiece containing the thermocouple unit on the bottom outlet of No. 2 Luwa (see sketch). The outlet was blocked with a by-product and the process re quired removal of the crosspiece for thorough cleaning. Cause The employee exposed himself to a high accumula tion of HiS gas by loosening the tank cover inside the building Orders were to always do this outside of the shed. Preventive Measures: 1. It will be ensured that tank covers are always loosened outside by: (a) Requesting that the train crew be given a written order by the car unloader before entering any tank car inside the shed. (b) Covers will always be loosened outside the shed, on day shift only, and in the presence of at least one workmate in the immediate area. 2. A special tool will be supplied to the employee to loosen the nuts. With this tool the employee will loosen the cover while standing in full upward position . thus keeping above the possible gas evaporation when the cover is loosened. 3. Self-contained breathing apparatus to be worn when opening tank covers. 5- - AT T.MS CMA 048719 A pipe breaking permit was issued by the leading operator who specified face shield and gloves as the necessary protec tive clothing. The men were wearing normal overalls, wrist length PVC gloves and hooded face shields He also cautioned the two men as to the possibility of hot liquid being present above the blockage. The blank on one horizontal branch of the crosspiece had been removed earlier in the day for inspection purposes, and process supervision had attempted to clear the blockage by rodding from this opening. The fitter proceeded to unbolt the bottom flange of the crosspiece and there was no liquid discharged when the flanges were parted. He then removed all but one of the bolts in the top flange and swung the crosspiece clear on the one remaining bolt. After waiting for some minutes and observing there was still no flow of liquid he called his mate to assist in lowering the crosspiece to the platform floor. The fitter was standing 4 treads up a set of platform steps and as his mate arrived at this point, a small quantity of hot liquid suddenly discharged from the bottom cone of the Luwa and splashed over the fitter's wrist and the mate's forearm. The bums to the fitter were minor but more serious in the mate's case. Both men were transferred to the hospital for treatment. The shift fitter was able to resume work after treatment. Cause: Both production and maintenance supervision and all personnel involved were interviewed and confirmed the details of the accident as reported. The committee deter mined the causes of the accident were: 1. Inadequate protective clothing was w'orn by both men. 2. The inability to positively determine the presence of a pocket of hot liquid in the bottom cone of the Luwa, despite extensive efforts to do so by process super vision. 3 The blockage could not be removed without removing the crosspiece. Preventive Mensures: 1. Personnel must wear full protective clothing which includes the full Nylon suit and PVC gauntlets when clearing blockages on these units and all routine instructions shall be closely followed. 2. Regular routine clean outs of the units should be car ried out starting at a two monthly frequency. 3. All supervision to be reminded at their next safety meeting of the need to pay particular attention to safety clothing requirements when hot, toxic or corrosive sub stances are involved. 4. Publicize the types of gloves available and their recommended uses. CASE HISTORY NO. 1632 Pressure Release from Pfaudler Kettle Description: During the cooling period, while processing a batch in a Pfaudler Kettle, the operator loosened the bolts of the manhole cover. When there was only one bolt left, hot material was released between the manhole and its cover, spraying up to a distance of 7 feet. Some of it entered the operator's right safety shoe causing bums. He was accompanied to the Medical Department for first aid and they sent him to the hospital. The investigation revealed that at 1:50 a.m. when the accident occurred, the temperature shown in the instrument chart was 94C. Prior to loosening the bolts, the batch had been vented and the gauge indicated zero pressure. Operating procedure indicates; "when the batch tempera ture reaches 85=C'., set on manual a jacket temperature of 8(TC.. open the manhole and the bottom valve of the kettle. The vent valve stays open." It is theorized that the pressure existing when the manhole cover was opened, was generated by the CO; desorption at a greater rate than the opened vent line could release. Cause: Unsafe operating procedure. Preventive Measures: 1. Insist on observance of operating procedures. 2. Eliminate the opening of the manhole cover until the transfer is almost completed. CASE HISTORY NO. 1633 Resin Reactor Erupts Description: A research technician sustained multiple sec ond degree burns over his face, arms and upper torso when a 100-gallon reaction vessel in the research pilot plant erupted through a covered, but unbolted 4-inch sample port. He was sprayed with phenol-formaldehyde resin which was at approximately 125-135C. Two other men in the operating area were also partially burned; one required overnight hos pital observation and medication and the other required only first aid for superficial bums. Just prior to the accident, at approximately 4:50 p.m., a routine sample had been taken for melting point. This sample is used to determine the adequacy of a devolatiliza tion step carried out to remove water and unreacted phenol and formaldehyde. The reactor agitator had been stopped, the sample port cover unbolted and the sample taken using specified safety equipment, viz. safety glasses, rubber gaunt let gloves and a hard hat. Slight vacuum was applied on the kettle to sweep air into the sample port and prevent exposure to kettle vapor. After the sample was taken, the sample port cover was replaced on its bolts but not bolted down as procedure specifies. The agitator was started and almost simultaneously the contents of the reactor erupted forcing the 15-pound sampling port cover off and spraying the technician, two other men and equipment in the area with hot 125+C phenol-formaldehyde resin. The three men involved in the accident were met coming down the grated stairway leading to the reactor level by another man passing through the pilot plant. He assisted them in getting under the two emergency showers located in the pilot plant and called for additional help. The injured man's clothes were cut off as completely as possible and his skin washed with soap and lukewarm water. This minimum amount of rubbing caused some peel ing of the skin and resin and was halted. After washing the injured as well as possible under the cold shower for over 15 minutes, he was then placed under a warm shower 6-- -- CHA 048720 in the Research Department for five minutes and then transrted by ambulance to the hospital emergency room. A combination of the rapid response by people in the area and excellent first aid treatment resulted in the injured man suffering only second degree bums. No chemical bums or toxic effects were experienced by the injured despite the fact that the erupted resin contained approximately 15Cr of unreacted phenol. Cause: Inadequate procedures. Analysis of resin samples from the reactor, erupted resin on the equipment, and a sample taken from the reactor 15 minutes prior to the accident indicates that during the time the technician was taking the reactor sample (just prior to the eruption) the vessel contents were still reacting and essentially at the boiling point of the mass. With the agitator shut off for several minutes to facilitate sampling via a tube probe, the exothermic heat of reaction, though relatively mild, was not dissipated throughout the batch and resulted in localized heat buildup and super-heated batch contents. When the agitator was turned on after the sampling the rapid thermal mixing of the resin and immediate vapor expansion of the volatiles resulted in enough pressure build up to activate a 2 psig swing check relief valve, hurl the sample port cover off its opening and spew resin over the technician and equipment, Failure to bolt down the manhole cover was an operational cause. Although bolting down the manhole cover would not have prevented the high pressure development, it would have contained the erupted resin in the emergency pressure Hief tank and prevented the injury. Other Comments: The men were wearing prescribed safety equipment. Glasses obviously saved the eyes of two men. Gloves protected the hands and lower arms of the man taking the sample; he was the one most severely injured. Preventive Measures: The process involved in this incident is different from standard phenol-formaldehyde polymeriza tion. It involves a mild secondary reaction converting phenol formaldehyde ether groups to a long chain (Thermoplastic) resin, and sampling to determine end point of devolatiliza tion is undertaken on a mixture which is at its boiling point at atmospheric pressure. 1. New procedures have been established for manufac turing and sampling this specific material as follows; (a) A stepwise devolatilization will be carried out to ensure completion of the secondary reaction before sampling for end point. (b) Devolatilization will be carried out under vacuum. At the time the sample is to be taken, the reactor will be raised to atmospheric pressure and thereby be safely below its boiling point. 2. Process safety audits of the pilot plant and phenolic research laboratory will be initiated immediately. 3. Manufacturing locations should critically review their process sampling procedures and required safety equipment. The research and pilot plant department will do so as part of their process safety audits. Chemi cal goggles are recommended as an improvement over safety glasses for this operation. 4. All phenolic resin manufacturing locations producing this type of product have been sent specific informa tion regarding this accident. Details of the technical aspects of the concerned reaction will be com municated. CASE HISTORY NO. 1634 Fire and Explosions Involving Vacuum Collection System Description: Two employees were in the process of cleaning and removing the explosive dust (Composition A-5) col lected in two primary vacuum collection chambers. As they were emptying one of the collection containers into a metal scrap explosives container, a flash fire occurred. One of the employees immediately rushed to the adjacent operating building and notified his supervisor, who in turn, activated the alarm and deluge systems. Evacuation of the line had been completed when an explosion occurred at the primary vacuum cubicles. A second explosion also occurred in the secondary vacuum collection and exhauster building, which was located on the other side of a barricade. There were no injuries. Cause: Exact cause unknown. Probable cause, friction static or pinching of explosives as the explosives were being trans ferred from one container to another. The primary explosives vacuum collection chamber cubi cles were completely destroyed. Severe damage occurred to the adjacent operating building, ramps, and the secondary explosives vacuum collection building. Total estimated damage amounted to $106,587. Approximately twenty-five pounds of explosives were present in each of the two primary vacuum collection cubi cles and approximately five pounds in the secondary unit. Preventive Measures: (a) To eliminate necessity for pouring explosive dust from one container into another, disposable bags should be used in collection containers and delivered to the explosives burning ground for destruction. (b) If pouring dry explosives dust is necessary, grounded, conductive, nonmetallic containers should be used. Floors should be of conductive and non-sparking material. (c) Wet primary explosive vacuum collection systems are preferred and should be used where possible. (d) Explosive dusts should be removed from dry explo sives vacuum collectors frequently enough to prevent unnecessary and hazardous concentrations of explo sives. (e) Good housekeeping should be maintained in cubicles containing dry explosive vacuum collectors to prevent accumulation of explosive dust. (f) The entire dry explosive vacuum dust collection sys tem should be cleaned weekly. Armed Services Explosives Safety Board Case History CASE HISTORY NO. 1635 Tank Entry Description: Chemical workers are still going down to their deaths in tanks. An employee of a large chemical plant CMA 048721 recently was asphyxiated when he entered a tank to clean it. The tank had been inerted with nitrogen and evidently he was not wearing an air mask or a life line. A co-worker wearing a filter mask and life line attempted rescue but, of course, he also soon lost consciousness since filter masks or ordinary gas masks do not supply needed oxygen. For tunately, the rescuer was pulled out of the tank by the life line and revised. The fire department was called and a deputy chiet wearing a self-contained breathing apparatus removed the body from the tank. Came: It is not only senseless and often fatal to enter tanks without taking common sense precautions but it is a violation of safety regulations in many states. If you are not thoroughly familiar with the precautions which must be followed when working in tanks, see MCA Safety Guide SG-10, "Entering Tanks and Other Enclosed Spaces." CASE HISTORY NO. 1636 Bromine Burns Description, A production operator received 2nd and 3rd degree burns about the face, eyes, and neck. The Maintenance Department changed out a leaking valve on the liquid bromine line. Standard practice for catching bromine drips is to fill a bucket half full of 25% caustic solution, catch and neutralize the drips when flanges are opened. This job was performed without incident, except the bucket containing caustic and bromine was not disposed of. Two shifts later, on the midnight shift, an operator was cleaning up the area and discovered the bucket. Due to the brownish-purple color of the material, he assumed it to be a dilute solution of potassium permanganate, a material commonly used in this area. The operator picked up the bucket and attempted to dump it in a grated trench containing hot water from steam traps. While being poured, the contents of the bucket reacted vio lently and erupted, splashing the operator about the face and neck. Although he was hospitalized for several days, the man recovered without permanent injury. His eyes were not permanently damaged because of his safety glasses. Come: Subsequent to the accident, it was demonstrated in the laboratory that liquid bromine will drop through the caustic solution without being completely reacted, and form a phase of pure bromine in the bottom of the container. The color of the bromine phase gives the bucket contents a color easily confused with potassium permanganate, par ticularly at night under artificial light. Under certain temperature and agitation conditions, the two phases will mix and react vigorously. Preventive Measures: While a safer method of containing tend neutralizing bromine drips is under investigation, all maintenance and operating personnel have been instructed to promptly dispose of all buckets and similar containers of drippings and spills. The person who collects the material is responsible for its prompt disposition. CASE HISTORY NO. 1637 Eruption -- Pressure Dyeing Machine Description: In shutting down an electrically heated, air pressurized dyeing machine, routine procedure was followed without fault. Yet, when the machine was opened, hot water erupted, burning three employees, one seriously. Came: Residual pressure in the inner chamber forced out the hot water. Although the pressure gauge indicated zero, it was demon strated that some nominal pressure could be present at a zero reading. Doubt was also expressed over the reliability of the vent which is operated by an electric solenoid. Preventive Measures: Replace pressure gauge with one whose scale more closely reflects the operating range. Provide a mechanical valve and separate vent in the vent line before the solenoid to be manually operated. Establish pre-start-up checkout list in which all controls are proven operative. CASE HISTORY NO. 1638 Hoist Failure -- But The Warning Sign Was There! Description: A 540 lb. load dropped three ft. to the floor after the chain failed on a half-ton Lodestar Electric Hoist. The corrosive contents of the container splashed out but no injuries occurred. Cause: This particular hoist, although inspected weekly, was not "tom down" and thoroughly examined at the first signs of trouble. Erratic movement of the chain and chatter ing noise had been noticed when the hoist was in motion, previous to the failure. This had been reported, but the hoist had not been "tom down" because the noise had not been constant and the hoist inspection group had not found signs of abnormal wear on the chain. The chain failed because it became wedged in the chain guide which had broken some time before. Preventive Measures: 1. Are your hoists inspected often enoughObviously this should be based on frequency and severity of use. 8- - CMA. 048722 2. Are your operators aware that at the first sign of trouble the use of the hoist should be stopped ... until the hoist is repaired! 3. Is the slack-chain catch-bag (installed on some hoists) large enough to accommodate all of the chain and still ha\e free space? We believe that if the bags arc not large enough the chain does not have sufficient room to straighten out before entering the chain guide. CASE HISTORY NO. 1639 Phenol Burn Description: While experiencing trouble with a false reading on four load cells under a phenol head tank, a maintenance man received a phenol bum. The phenol head tank is supported on four load cells, but these cells were giving a false reading. The trouble was due to the weight of the discharge line off the bottom of the head tank. It was decided to remove this discharge line and install a flux connector in the line to relieve this weight. The head tank had no sight glasses on it, nor was there a valve directly on the bottom of the head tank, so it could not be shut off to the discharge line. The tank was pumped empty and then pumped a second ne to make sure there was no phenol in the head tank before the lines were removed. All tracers on the tank and the discharge line were shut off so that any material left in the lines would become solid. Phenol becomes a solid at temperatures below 105F. After disconnecting the tracers, the maintenance men waited a period of time for the lines to cool off and for any phenol that might be trapped in the lines to set up. The bolts on the connecting flange were loosened and a screwdriver was inserted between the flange faces so the line could drain if any liquid remained in the line. There was no liquid drainage at this time, so the maintenance men started to remove the bolts from the flange. As they started loosening the bolts, several gallons of the liquid phenol started gushing out of the flanges. The maintenance men were wearing face-shields, safety glasses, rubber gloves and aprons. The resulting injury was a small bum about the size of a dime on the face of one of the men, which probably splashed in behind his face-shield as he ran from the area. Preventive Measures: 1. Install sight glasses on the head tank so that a visual determination can be made to insure that the tank is empty. 2. Install a valve on the bottom of tank so tank can be shut off from existing lines. 3. Install a bleed-off line in the discharge line so that any material in the line could be bled off. 4,. Hook hot water tracers into cooling water lines, then when maintenance work is needed, cooling water w ould lower the temperature of the phenol well below the 105F melting point. CASE HISTORY NO. 1640 Rupture Disc Fails to Protect Description: This incident points out a hazard in the use of rupture discs and relief valves that is not readily apparent. Fortunately , in this instance there was no injury to persons although the equipment was seriously damaged. An autoclave was charged with reactants and inadver tently was charged with an excess of material. The resulting reaction overpowered the cooling capacity of the reactor and pressure built up rapidly. The vessel was protected by a rupture disc and a safety relief valve in series. Although the plant standards provide for a small vent (try cock) to the space between the rupture disc or relief valve, it appears that this vent was closed, plugged or may not have been installed. It also appears that there was a leak in the rupture disc itself which permitted pressure from the reactor to build up in the space between the rupture disc and relief valve. This would have the effect of pre venting the disc from rupturing at its normal design pressure. As a result, pressure built up in the reactor itself resulting in failure of the reactor itself. Preventive Measures: Two methods of preventing such a failure are suggested. One method would be the installation of a pressure switch and alarm to the space between disc and valve to give warning of any pressure increase. The second method would be the provision of a permanent vent at this point. Standards for installation of relief devices on reactors should include these provisions. CASE HISTORY NO. 1641 Flammable Work Clothing Description: While arc welding, an employee had his work clothing ignite and continue to bum. Fortunately, the fire was extinguished without injury. We have also heard of a similar experience in another company in which the employee received third degree bums. The material in both cases was regular work clothing (shirt and trousers) purchased commercially. Similar cloth ing in the past has been all-cotton and, while it will bum, does not ignite readily from welding sparks and has not created a fire problem. Preventive Measures: We are starting a thorough investiga tion of materials now used in work clothing, especially of the "permanent press" variety. It should be noted that one synthetic fabric "Nomex" has been found to have excellent flame resistance. It is, however, quite expensive. Its use may be merited in some situations. CASE HISTORY NO. 1642 Operator Burned Moving Pressured Line Description: Operator attempted to insert a pressured line further into the loading port of a tank truck. It was his intent to take up slack in the safety chain, which was already -9 -- CMA 048723 snapped, so that there was no possibility of the pipe coming out of the opening. He lost control of the pipe, however, and the end came out of the port. Caustic splashed against the manway and deflected up into his face. Line pressure was approximately 100 p.s.i. The burns he sustained resulted in loss of sight in his left eye, and minor bums to inside of mouth. The operator was wearing monogoggles and hard hat. with the monogoggles strap over the bach of the hat, and the monogoggles over his eyes. Can.sc Neglecting to shut off pump before relocating load ing pipe. Operator assumed he could do job even though line was under pressure. Preventive Measures: 1. Re-emphasize to all employees that moving equip ment, or lines under pressure, are not to be worked on. 2. Installation of better tie down device for loading arms. CASE HISTORY NO. 1644 Walk-in Refrigerator Description: The injured employee together with a coworker was working inside a walk-in refrigerator containing various chemicals. After working for some time in the refrigerator, they noted headaches and eye irritation. They reported to the medical department and were treated for chemical irritation of the eyes. The investigation disclosed that one of the pails containing an irritating chemical was leaking because of corrosion on the bottom chime. Cause: A metal container of a corrosive and irritating chemi cal had been stored too long causing it to corrode and leak in a confined area. Preventive Measures: Closer inspection and inventory con trol of chemicals has been instituted. The Safe Work Permit will be extended to include work ing in any confined areas in accordance with Safety Standard for Method and Equipment S-6 "Entering Tanks and Other Enclosed Spaces". CASE HISTORY NO. 1643 Safety Goggles in Shirt Pocket -- Useless When Caustic Liquor Splashes Description: A pipefitter, accompanied by an apprentice, was assigned to replace a 2" pipe plug which was leaking on a 6" pipeline of caustic liquor. An operator of the Chemi cal group went along with them; his duty was to go and close the valve in order to replace the plug. Scale had accumulated around the pipe plug and the pipefitter, with a hammer, attempted to knock off this scale to find the exact location of the leak. It was only after a few light blows that the pipe plug broke and caustic liquor suddenly splashed from the line which had not yet been closed. The tradesman and his apprentice were both burnt to the eyes; their safety goggles were in their shirt pocket. The operator, who was standing some 10 feet away, received a discharge of liquor in the mouth and was burnt to the face and throat. He was fortunately wearing personal corrective glasses. Cause: 1. The employees were not wearing their safety glasses. 2. For some unknown reasons, a hollow body pipe plug had found its way into our stock. Solid model type of plug should have been in place. Note: The hollow type model wears out as much as three times faster under circulation of caustic liquor. Preventive Measures 1 The hollow type of plug has been canceled from our stock throughout the plant and replaced by the solid type. 2. The two employees of the trades group were disci plined. It will be emphasized among their coworkers that safety goggles should always be worn when work ing on liquid lines in this area. CASE HISTORY NO. 1645 Be Wary of Expansion Joints Description: A TFE expansion joint ruptured recently. One thousand pounds of molten (180C.) organic chemical cas caded through two levels of open grating and stairway to the ground floor. The sheet metal guard around the joint did not prevent splashing or protect personnel on lower levels. The absence of people is all that averted a serious injury. GUARDING WAS NOT ENOUGH! Cause: This type of failure could be caused by: 1. Over-extension or compression beyond recommended limits, 2. Misalignment. 3. Excessive temperature and/or pressure. Preventive Measures: Realignment of all expansion joints. -10 - CMA 048724 CASE HISTORY NO. 1646 enol Eruption Description: A research specialist sustained disabling chemical burns when superheated phenol erupted from his distillation unit. The injured was heating phenol, containing some water, in a glass distillation unit. The unit consisted of an Oldershaw Column and a 2-liter still pot. He was using an electric heating mantel and mechanical agitation in preparation for atmospheric dehydration by distillation. At a still temperature of approximately I40-150C. re fluxing started. At this point the agitator and heat were shut off to repair a vapor leak in a vapor line joint. After the repair was made, the agitator was connected and started. Sudden vigorous boiling pushed the agitator bearing out of the pot and separated the vapor line from the column. Phenol sprayed into the area. The injured was sprayed with phenol. He immediately washed the exposed area at the sink, and then went to the washroom where he continued washing with Isopropanol. After washing, he changed clothes and was taken to the dispensary. From the dispensary he was sent to a hospital for treatment and observation. Cause: Sudden vaporization of apparently super-heated phenol-water. Improper procedure. Full heat was being applied at the time the agitator and heat were turned off, but the mantel was not lowered from around the still pot. Seating of the liquid was localized giving rise to super-heat. ^Further, the liquid was not allowed to cool below its boiling point prior to restarting the agitator. Preventive Measures: 1. The use of safety shields for all distillation units was reviewed. 2. Proper procedure was reviewed and stressed: (a) Have the heating element easily removable instead of an integral part of the setup, fb) Make sure system has been cooled below the liquid boiling point before making repairs or starting agitator. CASE HISTORY NO. 1647 Engine Exhausts in Closed Building Description: Employees were affected by exhaust gases from a diesel powered truck air conditioner. The common carrier's refrigerated truck was in the branch's unloading dock for several hours without stopping the refrigerator. The exhaust fumes were picked up by the recirculating build ing air conditioning system and distributed throughout the branch. After about two hours practically all of the employees began to feel ill. The Fire Department was called and administered oxygen to some of the employees. Later, the warehouse manager collapsed, oxygen was adminis tered, and he was taken home. fcate; Obviously internal combustion motors should not be kept running in dosed buildings because their exhaust contains carbon monoxides and other harmful gases. Estimated lost time -- 5 days. CASE HISTORY NO. 1648 Fire Caused by 50% H2O2 Description: A lot of 333 export drums were filled with 50% hydrogen peroxide over a three-day period (July 27th to 29th) and were placed in outside storage on the asphalt pad of the Miscellaneous Chemicals shipping area, stacked in a double row, three tiers high, on wooden pallets. The drums, 15-gallon polythene containers in steel overpacks, holding 140 lbs. of peroxide, were inspected in the normal fashion for flaws before filling, and again, for leaks, after filling, before being placed in storage and covered with polythene tarpaulins to exclude dust and dirt. On July 30th a passing transport truck driver noticed smoke coming from the pile of drums. He returned to the gatehouse and notified the watchman who immediately called the power house to sound the fire alarm. He then called the city fire department as well as Works supervisory personnel. By this time, open flames had developed. The Works fire crew and the fire department arrived with in minutes and the fire was quickly extinguished. A number of pallets were destroyed by fire and 100 drums were so badly damaged with melted liners that the drums and contents had to be discarded. The remaining 233 drums suffered varying degrees of surface damage but the liners were intact and the contents are now being analyzed and returned to stock. Cause: A leak developed in one of the liners after the drums were placed in storage, allowing peroxide to escape through the drainage holes in the steel overpack and react with the wood of the pallet below, eventually producing sufficient heat to start a fire. Tests have shown that 50% hydrogen peroxide does not normally react with wood violently enough to cause ignition. In this case, however, very dry pallets which could have had some chemical impregnation, the black plastic tarpaulins, which could attract or retain heat, and the hot, dry weather may have combined to provide ideal kindling conditions. The present export drum has proven to be a satisfactory container for one-way shipments of hydrogen peroxide to foreign markets. Considerably less than 1% of the liners are found to be faulty on inspection and subsequent leaks are extremely rare. On only one occasion previously, slight charring of a wooden pallet occurred when a leak developed in a drum. Preventive Measures: 1. Export drums of this type should be stored outside in an intermediate area, and re-inspected before ship ment or transfer to a final storage area. 2. The height and length of storage piles should be limited to minimize the extent of damage in case of fire, and alleyways should be provided between rows to facilitate inspection. CASE HISTORY NO. 1649 Secondary Reaction or Unknown Instability Description: An explosion occurred involving a 3.000 gal lon stainless steel storage tank containing 1,500 gallons CMA 048725 of a nitro aromatic compound, para-nitro-meta-cresol. The eight employees in the area had left the building prior to the explosion, but two who had not proceeded far enough from the building were burned and one of these men later died. Extensive damage occurred in the building. The tank was used to feed product to the final stage of the process and was equipped with plate coils and com pletely insulated except for the manhole cover. Tank con tents were to be held at 154C. Melting point was 127C. and it was known that instability could occur above 220C. The explosion occurred during the initial start-up. Product had been fed to the tank intermittently for three days. The first product in the tank was subjected to temperatures in excess of 160C. as a result of initial steam application to the plate coils. Tests conducted since the explosion have shown that the product undergoes free radical induced polymerization at temperatures as low as 160C. This reaction takes place slowly, with little heat evolved. However, the reaction was being fed by additional product coming into the tank and the heat evolved was greater than the heat losses from the vessel. Over a three day period the temperature increased slowly to the second stage decomposition temperature, which under these conditions could have been reduced to 200C. Tests have also shown that the decomposition temperature is decreased on aging at temperatures above the melting point, the higher the temperature and the longer the period of time held, the lower the decomposition temperature. This decomposition reaction proceeds rapidly with a considerable increase in temperature and pressure. The tank was calculated to have ruptured at 358 psi. At that time the tank contents may have been above the autoignition temperature (525C) and could have ignited spontaneously on being released to the building or the prod uct spraying from the tank contacted a source of ignition created by the shock wave from the tank rupture (broken electrical fixture). Preventive Measures: 1. Hold smaller amounts of product and not for pro longed periods. 2. Maintain as low a storage temperature as is consistent with preventing solidification. 3. Maintain temperature control using two separate tem perature reading instruments, one of them recorded. 4. Maintain emergency cooling system for use if tem peratures start to rise. 5. Provide the largest possible vent on the storage vessel. 6. Determine that there is no possible holdup permitted in heated equipment or piping. 7. Potentially hazardous compounds will be tested to relfect the conditions that will apply in plant operation. Any contemplated change in the plant will require reevaluation and additional testing. CASE HISTORY NO. 1650 Acetic Anhydride Description: The injured was standing inside the Super visor's office, near the door, when the Analyst operator entered carrying two 10 oz. glass stoppered sample bottles containing acetic anhydride at 98.57L As he passed the injured, one bottle slipped out of his hand and hit the concrete floor. The sample bottle did not break, but the stopper flew out and some of the contents of the bottle splashed upwards into the injured's left eye. Some also splashed the operator carrying the sample up to the height of his thigh. Cause: Failure to follow procedure (sample basket not used). Preventive Measures: 1. That at all times samples be carried in the baskets provided. 2. Supervision to ensure that these safety measures are enforced. 3. All eye injuries are to be treated as serious until show n to be otherwise. CASE HISTORY NO. 1651 Cleaning Mechanical Equipment Description: A printer operator received severe lacerations to his left hand which required 81 stitches. He was cleaning a rotating rubber print roll using a rag in either hand at an open, in-running nip. A web of material was running through the nip at the time. One of the rags was a dry one for the final wiping action. The dry rag caught in the nip which had a gap of approximately 1/4". His hand was pulled into the nip at which time both he and the man beside him pulled the emergency stop cord. This braked the nip rolls to a stop and opened the gap another 1/2" by means of a timed electric screw . Another employee went to the machine control panel and operated the electric raising screws with the manual control. The injured was released with the badly bleeding wound. An experienced first aid man helped reduce the bleeding until he was taken to the hospital by plant personnel. Cause: Failure to follow procedure. The accident occurred because the injured failed to raise the printer bed roll until the nip gap was at a safe opening and was not using the "idle" drive control for the cleaning operation which are two of the established plant safety practices. Contributing Factors 1. The web was being run during the cleaning operation in order to save time by feeding in the "leader" at the same time. 2. The print roll was a "special" one which had a rubber cover. Preventive Measures: 1. Cleaning procedures and operator training are being reinforced to emphasize the proper cleaning pro cedure. 2. Recently-completed metal screen nip guards will be installed. These will force the setting of a wide open nip to do a roll cleaning. These will be the first nip guards installed on printers in this plant. CMA 048726 CASE HISTORY NO. 1655 Question of Responsibility Description: A potentially serious situation developed dur ing the startup of a new 3-inch propylene pipe line. This w'as a long line extending from a tank farm area to an operating area of the plant. Much of the line was outside of the normal jurisdictional area of either the tank farm or the operating plant. During hydrostatic testing of the line, it was found that there were no drip connections at low points along the line. Eight such drip connections were installed following the hydrostatic test. When the line was put in service and filled with propylene, the operator who had opened the necessary valves noticed white vapor clouds blowing from three locations. Realizing that the situation was extremely serious, the operator started running back toward the propylene pump but found that a railroad train had blocked his route causing him to run a considerable extra distance in order to reach the pump. Operating people were informed and spray sprinkler sys tems tripped in the heater section of the cracking plant. The operator climbed to the pipe rack and closed the three valves on the drip legs which were discharging propylene. It is extremely fortunate that ignition did not occur as the vapor clouds were blowing directly toward cracking fur naces . Cause: Investigation indicated that all valves w'hich were ^ithin the jurisdictional area of the operating plant were properly closed and this was also true near the tank farm area. In the intervening space which was not under the direct jurisdiction of either area, three valves had been left open. Apparently operators had assumed that "someone else" had taken care of the pipe line between the two operat ing areas. There have been other instances of accidents caused by persons who had assumed that maintenance matters were outside of their particular areas of responsibility. Preventive Measures: There are two important lessons. First, that of making sure that responsibilities are correctly assigned for all areas and that the extent of responsibility is fully understood. The second point is that supervision should always be alert to the possibility that checking and maintenance outside of their assigned jurisdiction may not have been carried out. CASE HISTORY NO. 1656 Human Failure Causes Pipe Failure Description: A high pressure ethylene leak created an extremely hazardous situation. It is extremely fortunate that jgnition of ethylene escaping at a high pressure did not peur. This leak occurred at a pressure gauge connection on the second stage discharge of an ethylene compressor. This connection consisted of a stainless steel pipe nipple specified as an ANSI Schedule 80 stainless steel pipe. Actually, it was found that a Schedule 40 nipple had been used in error, It is also fortunate that the connection did not fail com pletely. The leak was noticed by the compressor operator who notified his foreman. The foreman requested a replacement nipple and, while waiting for it, applied a piece of wire to the valve on the nipple in an attempt to keep the leak from opening up further. The compressor was left in operation. About a half hour after the leak was noticed, the foreman called the Safety Department for a safe work permit to replace the nipple. The Safety Department representative on arrival felt that the leak was serious enough to justify application of water to disburse the gas. With the help of the Fire Department, water spray was applied manually for about 10 minutes until the compressor was shut down. Preventive Measures: This incident again demonstrates the hazards which can be created by substitution of specified materials in the field. There was also delay in this case in proper notification of a serious situation. In general it is much better to be overcautious than to take a chance when spills or leaks of flammable gases or liquids are involved. CASE HISTORY NO. 1657 Chemical Plant Accident Re-emphasizes Old Lesson Description: This accident again emphasizes the seriousness of a type of human failure that has happened all too often in chemical operations. An ortho-nitroaniline (ONA) reaction went out of control resulting in overpressure and consequent violent rupture of the reactor. Four men sustained disabling injuries. The building was destroyed and damage to the adjacent area was widespread. ONA is produced by reacting orthonitrochlorobenzene (ONCB) with aqueous ammonia. ONCB is pumped from a storage tank to a volumetric measuring tank for charging to the reactor. The reactor was being charged with ONCB at 7:15 p.m. When the sight glass in the charge line failed to run empty in the usual time, the operator realized he had forgotten to shut down the pump from the ONCB supply tank to the measuring tank. An interlock, normally used to prevent this error, was not in service due to the temporary use of a tank car and temporary feed pump while the regular ONCB storage tank and pump were out of service for repair. Operators had been cautioned to use extra care in charging while the interlock was out of service. Assuming a probable overcharge of ONCB, the operator intentionally undercharged the ammonia to avoid over loading the reactor, He did not report the batch abnormality to his supervision. After heat was applied to raise the batch to the reaction temperature, difficulty was experienced in controlling tem perature and pressure by application of cooling water or by release of ammonia vapor to an absorber. By 12:18 a.m., pressure was rising rapidly in spite of an open manual vent line, and the rupture disc and relief valve opened. The operators ran for the exits, but the reactor exploded in a matter of seconds. -14- OlA 046721 CASE HISTORY NO. 1652 Truck Canopy Guard Tested Description For over fifteen years this company has fabri cated and installed its own canopy guards on industrial power trucks. The decision to do this was made when it was found that, unfortunately. most factory-installed guards would not provide adequate protection against a direct, heavy blow from above. The locally-made guard was carefully engi neered and extensively tested to withstand any normally expected load of falling product or material. Recently, however, the guard was given its severest actual field trial -- and performed beautifully. A fork truck operator assigned to a warehouse in the Stores Division was moving under a pallet load of light material when he caught movement in the comer of his eye. The movement, he quickly realized, was that of a 1,720 pound roll of paper toppling at him from across the aisle and 16 feet in the air. He tried to back his Clark counterbalanced truck clear of the falling stack of paper, but was unable to react in time. Fortunately, he did just as he was taught in the com pany's Power Truck Operators' course -- he stayed with the truck. The roll hit the mast a glancing blow and struck full-force on top of the canopy guard before landing on the floor. The driver suffered no injury, but did explain to an Industrial Safety Department investigator that he could not talk for five minutes after the incident. rolls were stored four-high on end on four-way entry pallets. Following the incident, supervision took a second look at the use of four-way pallets for paper storage and decided to revert to the use of two-way entry pallets until additional tests can be made. It appears that the four-way skids do not offer the necessary stability for such a heavy load of this shape. CASE HISTORY NO. 1653 Sodium-Moisture Explosion Description: While operator was rolling a 55-gallon drum containing 4"-5" of sodium sludge mixed with soda ash toward disposal area, a pressure-buildup occurred inside the drum. Although the lid had been securely fastened, it blew off, hitting and fracturing employee's right wrist. Cause: Investigation revealed there was moisture in the drum, causing the explosion. Preventive Measures: Drums containing sodium sludge will no longer be sealed, and will not be held overnight before being taken to disposal area. Not only did the incident make the employee realize the extent to which he was protected on his truck, but it made a sizable impression on the guard itself. The two-inch, heavy-wall, steel pipe guard was bent down (Photo #1) slightly, and the bolts holding the fore and aft whip sockets which anchor the guard were stretched as much as 3/4" (Photos #2 and #3). Even the massive counterweight at the rear was pushed back. Preventive Measures; In addition to the unexpected test, another lesson was learned. The 36" diameter, 45" wide CASE HISTORY NO. 1654 Chemical Exposure Description: Dimethylsulfate refining still had been shut down to test the system for air leakage. While insulating piping on the same DMS still system, a mechanic received DMS exposure, for which he was treated at the plant hospital and released when no symptoms of distress developed during the next five hours. Respiratory inflammation developed during the night, and he was hospitalized the next morning. Cause: Maintenance employees not needed in the area dur ing pressure test. Preventive Measures: Only necessary personnel will be present when testing is being done in this area. -13- CMA. 048728 Cause: While the absence of the interlocking system ^Aributed to this accident, the lesson we wish to reUPtasize is a type of human failure. This is the tendency of an operator, having made one blunder, to attempt to correct it or "cover up" by making another. Preventive Measures: We must do everything possible to let our people realize that, having made an honest mistake, the thing to do is to bring it immediately to the attention of supervision. From then on it becomes the supervisor's responsibility -- not the operator's. And another thing we must drive home is to get our supervisors to act in such a way that operators will be encour aged to report blunders. CASE HISTORY NO. 1658 Treatment of Phosgene Exposures with Hexamethylenetetramine Description: Six men suffered exposure to phosgene and their attending physician, a general practitioner in the area, treated five of the exposed men with hexamethylene tetramine, also known as methenamine and urotropine. None of these developed any measure of pulmonary edema or other expected symptoms. The sixth man who claimed he had not breathed any phosgene was not given the medication and developed pulmonary edema some six hours later, was hospitalized, and eventually became a fatality. any inquiries have been received for supporting literareferenccs and for further information on the method of administration, dosage etc. The following descriptive material has been made avail able by a member company of the Association. It does not have the endorsement of the Association's Occupational Health Committee but is published here for the information and consideration of those concerned. EDITOR Phosgene Poisoning Mechanism of Phosgene Poisoning: Earlier, it was believed that the action of phosgene was equivalent to that of the nitrous gases and chlorine, since upon contact with moist mucous membranes active hydrogen chloride is set free from the phosgene. This is, however, improbable according to the experiments carried out in the last world war. The action probably depends (Gilman and Cattell) on a direct chemical reaction of the C'-O groups set free, making possible the rapid combination with a whole series of substances (e.g. amino acids -- i.e., protein compounds and numerous en zymes). Thereby, metabolic processes important to life are blocked and, above all, certain amino acids are destroyed. It can be shown in animal experiments that the poison action begins immediately and is detectable long before the occurr ence of lung edema. Certain substances have the power to intercept the active C-O groups, and one of the best msphylactic agents as shown through animal experimenta- is hexamethylenetetramine. Nature of Poisoning: Exposure to low concentrations may not produce symptoms for several hours -- 3,6 or 8 depend ing on the concentration and duration of exposure. Suddenly very heavy irritation phenomena in the breathing area occur with the signals of a lung edema. In contrast with these drastic changes with regard to the lungs, after the latent period local irritation phenomena of the eyes and the throat remain in the background. Rapidly, a very heavy cyanosis develops with racking coughs and abundant brownish-foam ing sputum and increasing respiratory distress. The pulse is light and frequent. In many cases, in this state of the heavily toxic lung edema, death occurs by asphyxiation. Blood thickening is typical in all heavy cases (increase of the MB, the red cell and the hematocrit) because of plasma loss. The lung picture shows the typical form of lung edema with fine to coarse spotting of the entire lungs. Even if the poisoning by the lung edema is overcome, subsequent heavy pneumonia may result as in the nitrous gas poisoning, since secondary infections develop very easily in the dam aged lungs. These infections include embolism, myocardial damage, neuritis, encephalitis and perhaps metabolic distur bances. Death, however, can also be caused by circulatory disturbances. A common aftereffect of phosgene damage is a bronchial asthma and emphysema (Buess & Lerner). With very high concentrations, the otherwise typical latent period is lacking. The irritation phenomena begin very rapidly, leading to vomiting, gastric pains and vertigo. With out development of a lung edema, death occurs very shortly after the occurrence of the symptoms, apparently by bronchial convulsion. Prognosis: If the poisoned one is still alive after 24 hours, the prognosis is generally favorable. Pathological Anatomy: Lung edema is foremost, together with a strong reddening of the bronchial mucous membrane and perhaps the eyes. Therapy: Hexamethylenetetramine (Methenamine, Uro tropine) administered intravenously in a 20 percent solution (one 5 ml capsule with 15 ml sterile water injected over a 5 minute period). Precaution with chemical lung edema: If any lung edema is noticed after the inhalation of a lung poison, the patient must be watched closely and the blood pressure and the respiration checked half hourly or hourly. Prophylaxis of lung edema: 1. Corticosteroid injection: Immediate injection of 250300mg. Prednisolene succinateorphthalate(Meticortelon soluble, Soludacortin, Ultracorten H). Accord ing to special experimental experiences, the oc currence of a chemical lung edema can be hindered and this represents the best presently known mode of action. On the 2nd day, 50-75 mg. is given and then dropped down gradually. 2. Absolute rest, also with apparently light poisoning. Complete abstinence from further work, walking and driving etc., since thereby perhaps a later occurring lung edema would be much heavier. 3. Heat, but no introduction of liquid. 4. Oxygen introduction: Very important, e.g. with Oa-mask or any of the usual systems. In practice, the small Oa cylinders, which can be carried easily in a car, are especially suitable. In this case, up to -15- CMA. 048729 80% 02 can be administered, not more than 6 liters per minute. Thereby, however, sucking out of the edema liquid should not be forgotten. The 0-2 introduction must be regulated so that the possibility of the cyanosis of the patient disappears. Combination of Oa with helium (1:4) (Dickermann) is indicated in the combination of a lung edema with bronchial asthma, since the helium lowers the inhala tion resistance strongly and is non-toxic. 5. Hypertonic glucose solution 40%, 60 ml. intravenously. 6 Non-bloody venesection can occasionally also bring a considerable improvement. By the application of sleeves of 2 blood pressure apparatus on both upper arms, as proximal as possible, and by corresponding pressure regulation of venestasis, however with incomplete ischemia, and effect thereby the with drawal of a large amount of blood from circulation. The effect can be strengthened by the application of sleeves to the lower extremities. In this manner, ca. 600-700 ml. blood is withdrawn from the central cycle. 7. Venesection of 300-400 ml. Outstanding effect in many cases; however it can be omitted if the above precautions are adequate. The withdrawal of 250 ml. blood effects a drop of the lung pressure by 50 mm. (Sarnoff). Caution is required with heavy cerebral sclerosis not to take too large a venesection due to the danger of an encephalitic malacia. 8. Reduction of the mucous formation: Experimentally, good results have been attained with the application of`'methylpolysiloxane." Preparation: (XEC 151 -- Dow Corning Corp., Midland, Mich.) applied as an aerosol in a dilution of 1:10 with water (Nickerson and Curry). Alcohol solutions (30-40%?) have appar ently a less favorable effect and affect many by central depression. First Aid Procedure for Phosgene Exposure 1. Have patient in Oat position -- head may be elevated. 2. Cover eyes with wet towel -- (Silicone Oil is irritating but not harmful to the eyes). 3. Attach bottle of Silicone Spray to atomizer tube on suction machine, checking first to be sure it is working properly. 4. Spray Silicone Mist with each inhalation for 10 minutes. Wait 15 minutes and repeat as above. Do this for four consecutive times which gives 40 minutes total of Silicone Spray. 5. Inhalation of oxygen may be given if necessary. Notes: Silicone Oil should be kept in bottle attachment at all times. Keep two hand atomizers filled with Silicone Oil to be used in case more than one person is involved in an incident. In case of severe or questionable exposure always contact company doctor for further treatment. Literature: Suess, H., and Lerner, R.: Zschr. Praventivmed. 2,64 (1956). -- Buscher, H.: Grun- andGelbkreuz. Hamburg 1932. -- Counice, P.C., and Ross, G.L.: Lancet 1946, II 670. -- Plury, P., and Jemick, F.: Schadliche Gase, Verlag Apringer 1931. -- Gilman, A., et al.: Advances in Milit. Med., Little Brown and Co., Boston 1948. -- Loschke, E.: Die wichtigsten Vergiftungen. Vlg. Lehmann. Munchen 1933, S. 129. -- Muntsche, O.: Leitfaden der Pathologie und Therapie der Kampfgaserkrankungen. Leipzig 1932. --Zangger, H.: Die Gasschutzfrage. Vlg. Ruber. Born 1932. CASE HISTORY NO. 1659 Two Hydrogenation Incidents (a) Description; A hydrogenation process was involved in several incidents which fortunately did not cause appreciable damage or injuries. An ignition occurred in a 3,000 gal. stainless holding tank which blew the 40 lb. manhole cover over a 20 ft. high building. The ends of the tank were also dished out by the explosion, and the tank had to be removed from service. The accident was caused by a frozen flame arrestor which did not allow the small amounts of entrained hydrogen to escape plus a pyrophoric catalyst which had passed through the filter and dried on a hot steam coil above the liquid level. Presently available flame arrestors will not effectively stop a hydrogen flame propagation. Therefore, the arrestor will be removed from the tank vent which will be fitted with a weather shield. Steam jacketed flame arrestors are available for use in services where icing up is a problem. The problem of catalysts getting past the filter has not been completely solved. Periodically cleaning the tank of catalyst lines and keeping the steam coils below the liquid level should reduce chances of another ignition. (b) Description; The other hydrogen incident occurred when a 2,250 psi rupture disc on a hydrogenation reactor failed at about 1,000 psi. The vent line from the disc had two 90 and one 45 elbows. These hampered the sudden pressure release sufficiently to cause the vent line to whip and damage the explosion vent wall on the high pressure cubicle. Hydrogenations are operated by remote control so no one was injured when the vent line attempted to straighten out its bends. Rupture discs often fail from fatigue and should be replaced periodically depending on pressures and the corro sive properties of the materials being processed. Elbows in vent lines should be kept to a minimum or the vent line sized to compensate for additional elbows. In this instance only one elbow was used when the vent line was replaced. CASE HISTORY NO. 1660 Laboratory Explosion Description: This incident took place sometime after normal working hours. A bottle of chromous chloride solution exploded on a shelf in a storeroom, scattering chemical and glass into the adjoining laboratory. Since the explosion took place while the laboratory was empty, no one was hurt; but clearly at any other time of the day there could have been a serious accident. -16- CMA 048730 The fragmented top of the bottle was found with the astic seal still intact, which indicated that it had never Ren opened. Remains of the label also were found, and there were no indications of the existing hazardous nature of the chemical or the shelf life. The bottle was dated December 1968. Cause: The exact cause of the explosion is unknown. Probable cause. Normal heating and cooling over a period of time caused moisture to enter the bottle in sufficient quantity to react with solution, causing excessive pressure. Preventive Measures. 1. All chemicals which have a suspected shelf life or those which are known to be hazardous when stored for long periods of time will be labeled and dated at the time of purchase with a definite disposal date included. 2. Laboratory supervisors will be required to check their inventory every six months and discard those chemi cals which are outdated. 3. Manufacturers or suppliers which sell chemicals directly to the laboratories without passing through normal channels will be required to carry this informa tion on their label. CASE HISTORY NO. 1661 Acetone and Chloroform: An Explosive Mixture In the course of disposal of waste solvents used for chro matography, chloroform was added to a residue bottle con taining other solvents including acetone. A strongly exother mic reaction ensued, and a few seconds later the bottle exploded with considerable violence; two people were injured by flying glass. There was no immediate explanation since the only materials present were waste solvents which would normally be regarded as innocuous and comparatively unreactive. Dr. L. Bretherick of BP Research Centre, Sunburyon-Thames and Mr. A, Kruk-Schuster of Laboratory Chem icals Disposal Company, whom I approached for advice, inform me that chloroform will undergo a highly exothermic condensation with acetone to form "chloretone" (1,1,1trichloro-3-hydroxy-3-methylketone). The reaction is basecatalysed but basic substances may well have been present from the chromatographic materials. Moreover, in contact with alumina, acetone will condense to yield mesityl oxide and phorone, which may have triggered the reaction, Chloroform and acetone are common laboratory reagents which should be kept apart, and in particular, separate ar rangements should be made for disposal of residues. (From a letter to the editor "Chemistry and Industry" Feb ruary 1970.) CASE HISTORY NO. 1662 Electrocution Possibility Description: A potentially very hazardous situation developed when a structural framework and associated pip ing for a water spray system for a horizontal flare w'as being moved. This unit is approximately 18 feet high, 12 feet wide, and 18 feet long. It was being moved to location by dragging it by a winch truck and crane car. The unit was being pulled beneath an overhead power line at 12,500 volts. Three of the legs of the unit had passed beneath the line which was less than 18 feet above ground. The fourth leg struck the line creating an arc and energizing the framework. Realizing they had struck the line, the operators of the truck and crane car remained on the equipment and backed the unit away from the line. Only seconds before the unit was struck, there were personnel pushing on it in an effort to guide it. Fortunately, they were not touching it when contact was made. Preventive Measures: An accident investigation committee, set up following the incident, has recommended a minimum of 27 feet in height for all high voltage wires at their lowest sag points with a 30 foot minimum at all road crossings. It was further recommended that where it is necessary to cross roads that consideration be given to running the high voltage lines underground. Where this is not feasible, signs should be installed beneath the lines to warn of their exis tence. The report has also recommended that a clearance of not less than 6 feet be maintained unless special precautions are set up. CASE HISTORY NO. 1663 Type EE -- Electric Lift Trucks The term TYPE EE is used to designate battery powered trucks in which parts that may present a fire hazard are enclosed or shielded. Sometimes called "vapor-proofing" or "totally enclosed, this construction is usually specified for trucks working in storage areas in which leaking liquid product containers are a source of flammable/combustible vapor. If the vapor is ignited, the resulting fire could cause considerable damage to product and building, and injury to personnel. On a recent visit to a Regional Distribution Center, a safety engineer discovered that some electric trucks at work in the warehouse did not comply with the Type EE construc tion specified in the purchase order. It was realized that the trucks presented a serious hazard if used in flammable product storage areas. Arrangements were immediately made to have the manufacturer correct this situation. The standard reference for such electric battery powered industrial trucks is Underwriters' Laboratories Standard UL 583, which specifies both truck and battery requirements. However, this is to no avail if the manufacturer, his local representative, and the purchaser have not checked the vehi cle for compliance with the requirements. It is easy to avert this situation. A copy of the standard may be obtained from Underwriters' Laboratories, Inc., 207 East Ohio Street, Chicago, Illinois 60611. When truck and battery are received by the purchaser, and before the truck is operated, maintenance personnel should assure that the UL specifications have been met. The truck should not be operated in atmospheres with flammable/combustible 7- CMA 048731 vapors until deviations from the standard are corrected by the manufacturer. CASE HISTORY NO. 1664 Aluminum Tank Failure Description Glacial acetic acid is stored in vertical aluminum tanks 20 feet in diameter and 20 feet high. The lower 6 toot section of the tank was of 3/8 inch aluminum plate. The original coil type heaters were replaced with bayonet type heaters and at this time an opening about 2 feet wide and 3 feet high was cut into the side of each tank near the bottom. These cut-out patches were then rewelded into the tank from the outside. There was poor weld penetration and, as a result, it had become practice to close up minor leaks by peening the weld with a ball-peen hammer. While attempting such a repair, the welded patch gave way completely around the 2' x 3' patch except for one lower comer. As the tank was nearly full, this suddenly released nearly 400 tons of glacial acetic acid, causing bum injuries and fume inhalation to three men. Prompt washing down by hose and safety shower w'as helpful in preventing more severe injuries. Preventive Measures: Aluminum requires very good weld penetration in order to be effective. Butt welding of the old patch into the tank was not good repair practice. The replacement patches will be larger than the opening and there will be fillet welds on both outside and inside of the tanks. This large tank had only a 2 inch diameter vent. When the contents were suddenly released, the top of the tank was pulled inwards causing extensive damage. Venting was insufficient; replacement vents are 4 inches in diameter, CASE HISTORY NO. 1665 Tank Venting -- the Do's and Don'ts Tank venting problems have long plagued us and led to potential or actual accidents. Concern for this problem has again been brought to a head in the Accident Prevention Section by three potentially serious incidents -- all the result of plugged vent lines. In the first case, the driver for an outside oil company was bathed with #4 fuel oil when a pressure buildup on a large tank he was filling allowed the "black gold" to spray him as he broke his fill connection. Cases two and three both occurred when the plugged vent lines on two tank wagons caused a vacuum to be drawn on the tanks to the point where they collapsed as material was being drawn off. Fortunately, serious injury or property damage was avoided in these last three cases in the long series of tank venting problems. A survey of the files leads one to the same conclusion }in all cases -- open and adequate tank vents are critical to the safe and proper operation of liquid storage or holding tanks. Basically, tank vents are designed to maintain pres sure inside the tank at or near atmospheric conditions. Some special vents permit a few ounces of positive pressure in the tank to conserve the amount of vapor which may other wise be lost to the outside. These vents are called quite understandably, conservation vents. Generally, however, the vent on most tanks serves to allow free communication of air or liquid vapors between the tank and the outside so that the liquid may flow in or out freely. Unfortunately, a plugged or inadequate vent does not allow adequate pressure equalization. If air cannot escape during Filling, the pressure buildup may cause the tank to bulge or even rupture. Conversely, only a slight vacuum during unloading may allow the tank to collapse. Several factors are worth considering when attempting to insure positive and consistent vent operation; 1. Vents may plug most easily on tanks which contain viscous materials, crude solvents, polymeric mater ials, materials which can solidify at lower than normal temperatures, and corrosive materials. 2. Flame arrestors, which are usually provided on tanks containing flammable liquids, may easily become clogged or plugged. 3. It is most desirable to vent tanks straight up, however, this is not always possible. Practically speaking, vent lines should be as short as possible, have as few elbows as necessary, and utilize horizontal runs pitched back to the tank. 4. Vents should terminate in safe locations where va pors will not be drawn into buildings. 5. Valves should not be placed in vent lines. The solution to our mutual problem of plugged or inadequate vents is careful engineering and installation and a regular inspection and cleaning of all vents. Preferably, vents should be checked prior to filling or dis charging the tank. Cleaning should be done on a regular schedule and following any overflows (after the overflow isreported to the Industrial Safety Department). Care should be taken to include any permanent vents which may be mounted on building sides or roofs in the cleaning and inspection schedule. By implementing these suggestions, and carefully con sidering the do's and don'ts of venting, you, the user of tanks and tank vehicles, have made a start on solving the problem. As with most other safety projects, however, the attack must be continued and the word must reach the operator. We badly need to improve tank safety and can only do it with your concerned and lasting help, CASE HISTORY NO. 1666 Ethylene Oxide Polymerization Ethylene oxide once heated and then cooled may continue to polymerize, pressurize the container and explode. A group which studied several ethylene oxide tank car derailments involving explosions concluded that; 1. The initial fire heated up the tank cars sufficiently to cause the ethylene oxide to polymerize. 2. After the fire was extinguished and the car cooled to touch, the contents remained very warm due to the tank insulation. 3. Polymerization slowly built up heat and pressure caus ing the safety valve to relieve. 4. Vapor discharge ignited by catalyst or static. -18- CMk 048732 Safety valve did not reseat and contents exploded when the vapor pressure in the ear dropped and the flame ignited the flammable vapors within the tank. CASE HISTORY NO. 1667 Spilled Flake Caustic Description: Operator was adding flake caustic from small drum into tank manhole when some flakes spilled onto his trouser leg. Although employee thought he had brushed off the flakes, he later felt a burning sensation on the outer edge of his right foot; apparently a small quantity of caustic had entered the top of his high-top work shoe. Hospitaliza tion for skin grafting was recommended to promote more rapid healing. Cause: Inadequate clean-up after spill. Preventive Measures: Additional protective clothing will be worn when adding flake caustic. CASE HISTORY NO. 1668 Corroded Valve, Leaking Hose and Inadequate Equipment Description. A 3/4" bleed valve on the sulfuric acid header ,the Department 30 battery limits failed, spraying sulfuric 'id on a Waste Treatment processor and on an outside vacuum truck driver. An outside helper also received acid burns, probably as a result of contacting one of the other two men. The Waste Treatment Department was out of acid on the morning of January 17. Since their sulfuric tank (335T14) was to be entered for cleanout on the morning of January 19, a normal tank truck load of acid had not been ordered. Acid was to be picked up by vacuum truck if 335T14 went empty over the weekend. The Distribution Department was contacted by Waste Treatment on the morning of the incident for a place to pick up 1,000 gallons of sulfuric acid. The Distribution foreman surveyed the sulfuric system for possible location and the site at the Department 30 battery limits was selected because it was near the road and had been used for this purpose before. The Waste Treatment processor reviewed the proper special protective clothing (slicker suit, chemical gloves, boots, face shield, and goggles) with the driver, and the vacuum truck was moved to Department 30. The outside people wore goggles borrowed from the Waste Treat ment department and none of the other special clothing specified. The truck was connected to a 3/4" bleed valve by two lengths of stainless steel flex hose and a variety of pipe fittings at the valve. The stainless steel hoses were obtained in the Waste Treatment unit. Distribution was contacted and they started their sulfuric cid pump. Several leaks at the truck connection and from e hose were noted. Distribution was radioed that the T'ansfer was going to be blocked in to repair the leaks. Another stainless steel hose was borrowed from the AN unit and was attached to the truck. At this point the processor entered the east-west pipe ditch to help the driver remove the old hose from the bleed valve without remembering to put on his own protective gear. When they applied their wrenches to the union connection, the 3/4" bleeder snapped. Acid was sprayed on the two men standing on the pipes in the pipe ditch. The bleed valve was approximately shoul der high. The men scrambled to the road. Not knowing where a safety shower was located, they ran in search of one. It is felt that at this time the outside helper received the acid. The processor ran for the control room, but then saw the safety shower at the base of the Department 30 flare stack. He got under this shower and turned it on. This sounded the control room alarm. The AN foreman rushed outside and at the same time the outside men were running north through Department 30 looking for a shower. They passed one shower and were then caught by two AN processors and placed under the shower at the base of 30D1. AN notified the main gate and then notified Distribution of the spill. Distribution shut down its pump and blocked the pump suction and discharge. When the Distribution pro cessor went to AN, he found acid still draining from the broken bleeder. He returned to the pump and blocked in the pump's recirculation line. Also, the second Distribution processor stopped acid transfer from the barge unloading tank. Two fire monitors were turned on the spill area. The outside truck was moved 100 feet east to get it out of the spill area. After approximately 15 minutes under the shower, the driver was showing signs of shock. The men were then moved to Safety for first aid and then on to the hospital by ambulance. Inspection of the nipple that broke revealed that it was severely corroded internally. Cause: 1. Failure to wear adequate protective clothing. 2. Equipment failure. Preventive Measures: 1. Emphasize to all personnel that the procedures for wearing protective clothing when working on equip ment containing corrosive chemicals must be followed at all times. Particular emphasis should be placed on: a. The philosophy behind the procedure that we specify protective equipment because we presume failure of equipment. b. Work outside battery limits. c. Work on temporary facilities. d. Work on small piping where risk of failure is high. e. Work on systems in service even though they are not leaking. f. Work by contractors. 2. Survey the sulfuric acid distribution system to de termine if other corrosion has occurred. 3. Cap off all the unplugged bleed valves on this acid piping that are not in use. 4. Re-emphasize enforcement of safety requirements on the part of all contract personnel. 5. Complete the existing study to eliminate trucking acid to Waste Treatment. 6. Install loading/unloading area for acid and caustic. -19- CMA 048733 7. Several other aspects of this situation that were not direct contributors to the accident should be reviewed in safety meetings to prevent other accidents. a. The leaky hose had apparently leaked before and had not been repaired. b. A brass bleed valve was used in the hose hook up which is unsafe for sulfuric acid. c People u ere standing on pipes and not on adequate tooting. d. The plans for acid supply were not adequatelylaid despite the likelihood of runout over the weekend. air supply to the building had been temporarily reduced. Failure of the full speed relay on the building supply fan caused plant personnel to resort to half speed operation resulting in low air supply to the oven room. Some time after being loaded, the oven exploded totally destroying the oven and causing some other damage. Cause: This explosion was the result of accumulation of solvent vapors from the material being dried. It indicates the hazards created by solvent accumulation, a particular problem in batch type ovens where the entire load goes into the oven at one time. CASE HISTORY NO. 1669 Two Accidents Involving Chemical Spills Point to the Value of Safety Showers CASE HISTORY NO. 1671 Solvent Vapor Ignition by Diesel Engine Case #1: A production chemist was splashed on the hands, legs and stomach by a very corrosive chemical. He was directly below a safety shower when the accident occurred and his lab partner activated the shower. He was back to work immediately following minor treatment at the Medical Department and changing his clothes. Case #2: An electrician turned on a pump to check its operation and was badly splashed with 85# silver nitrate solution which sprayed out of a "cracked" flange, He was taken immediately to a safety shower a few feet away to flush off the chemical. The only evidence of injury were two small "burns" on the bridge of his nose beneath the pads of his safety glasses which prevented water from reach ing the skin. These two cases, which had potentially severe conse quences, point out the obvious need for immediate, thorough washing with large quantities of water before reporting to the Medical Department. This sequence of steps cannot possibly be over emphasized. The help that a fellow employee can give at this time is very important too. We should also like to reiterate the need for testing safety show ers periodically to clear the lines of sediment and corro sion which invariably accumulates. CASE HISTORY NO. 1670 Oven Explosion Description- This was a small batch oven. Interior dimen sions were 6'0" long, 3'0" wide and 6'9" high. There were double doors on each end. The oven was directly heated by electric resistance heaters in the duct above the oven chamber inside the oven shell. Air was recirculated by fan through the heater and the oven chamber. The oven was used for baking adhesive which had been coated on one side of 26" x 28" light gauge aluminum sheets. After coating, loaded carts holding about 100 sheets in skeleton wire racks are put in front of an exhaust hood for about 15 minutes before loading into the oven. This process had operated in this particular building for a number of years without trouble. When moved to the new location, it appears that there was less solvent removal by the ventilation systems -- in part because the normal Description: It is sometimes necessary to use a vehicle crane or other piece of equipment operated by a diesel engine in a place where there is a possibility of the release of flammable vapor or volatile flammable liquid from process or storage equipment into the atmosphere. The circumstances of a very serious accident involving fire and explosion occurring in England in May of last year has shown that the use of a diesel engine in such a situation may provide a source of ignition to a flammable atmosphere with disastrous consequences. During the routine start-up of a Nylon Intermediate Plant there was an accidental escape of hot cyclohexane. This formed a vapor cloud which subsequently ignited with explo sive violence. Neither the escape of cyclohexane nor the source of ignition were in any way associated with the actual process being operated in the plant. Cause: It is believed that the source of ignition was a dieselengined platform lift truck which was working in the area. At the time of the accident this vehicle, together with a diesel-engined mobile crane were standing nearby with engines idling. Both were being used for maintenance work. When the cloud of vapor reached the two vehicles, the engines began to race, to emit black smoke from their exhausts and make banging noises. The drivers were unable to stop them by shutting off the diesel fuel and the engines were racing too violently to allow a gear to be engaged to stall them. This was because the engines were running on cyclohexane sucked in through the air inlet over which there was no control. The drivers, realizing the seriousness of the situation, abandoned their vehicles and within a minute flash back occurred in the engine of the platform lift truck and ignited the vapor cloud. When the engines were examined after the accident, the air filter of the platform lift truck was found to show signs of internal heating and pressure. Laboratory tests showed that it was possible for the flame of a burning gas to pass through a similar air filter to atmosphere. It is believed that the uncontrollable racing of the engines was caused by the vapor in the atmosphere and led to inlet valve bounce (i.e. during the compression stroke) and the passage of a flame from the engine through the air inlet and filter to atmosphere and that this ignited the vapor in the atmosphere. No other likely source of ignition was found on the vehicles or in the area affected by the fire. -20- CMA 048734 A:t appears that ignition might have been avoided if it icen possible to stop the engines when the vapor reached CASE HISTORY NO. 1673 Corroded Pressure Cylinders The use of a diesel vehicle in this area was covered by the issue of a safety certificate which laid down the Description: Operator had just loaded a 100-lb cylinder point of entry and location in which it was allowed to operate. with dimethylamine when the bottom of the cylinder rup Before allowing entry, the area of operation had been shown tured. spraying his ankles with the liquid. to be free of flammable sapor by the use of an explosimeter. Since it may be necessary to operate diesel vehicles near Cause: Investigation revealed that the bottom of the cylinder equipment from which a flammable vapor or liquid could was corroded externally. be released to atmosphere, steps must be taken to modify such diesel engines to eliminate sources of ignition. Preventive Measures: All cylinders have been emptied and inspected, and those unfit for use have been discarded. In Preventive Measures- This incident indicates the desirability the future, all cylinders will be thoroughly inspected as of providing a control to stop a diesel engine if it should they are returned from customer locations. be surrounded by flammable vapor. This might be a tight closing butterfly or shutter in the air intake or, less desirably, a means for reliably stalling the engine. CASE HISTORY NO. 1674 Diesel fork trucks are available which have been approved for use in areas classed as Division I in the National Electri Eye Abrasion cal Code. However, at this moment we do not know how these approved trucks will behave when exposed to such Description: While operator was pumping solution from high concentrations of flammable vapor. 15-gallon reactor to 5-gallon can using a Randolph peristaltic It is suggested that where standard road trucks and diesel pump, pressure built up in base causing it to separate from locomotives may enter such areas that this possibility of length of rigid "Teflon" tubing which was inserted in the difficulty should be reviewed. It should also be noted that open can. Solution sprayed over the operator who was wear the same thing could happen to a gasoline or propane pow ing rubber gloves and safety glasses with side shields as ered vehicle. protective equipment. Prompt use of safety shower pre This incident also points out the possible desirability of vented more serious injuries. Cornea of right eye was i permanently installed gas detectors in critical locations abraded. Sympathetic reaction in uninjured eye produced Kund an alarm if dangerous gas accumulations occurred, pain, inflammation, and excessive lacrimation to the extent ome locations this method has been used successfully that he was unable to complete the full shift on the next to turn on spray systems -- activation of the spray system day. being a sufficient alarm in itself. Cause: Inadequate protective equipment. Preventive Measures: Goggles will be worn while dumping crude dye. CASE HISTORY NO. 1672 Caustic Reactor Description: A chemical operator narrowly escaped serious injury when he checked a foaming 200 gal. reactor. A caustic cleaning solution was being prepared which contained com mercial cleansers and caustic. The operator noticed solution flowing from the 2 inch overflow line. Believing that a sizeable amount of the solution had been lost, he turned off the steam sparger. Wearing goggles, he then opened the unbolted manhole and was struck in the face by the caustic solution which apparently bumped when the cover was opened. Preventive Measures: The operating procedure has been hanged requiring the bolting down of the manhole, and (|is not to be opened until the solution has been pumped ut of the reactor. It should be noted that eye protection saved this man from serious injury. Also there was a safety shower within 15 ft but he elected to use a cleaning sink prior to going to a ..bower room in a building next door. CASE HISTORY NO. 1675 Misleading Labels The Technical Safety Laboratory was requested to deter mine the flammability characteristics of a polyurethane floor finish. The label on the can indicated a flash point of 1)4F. which is in the general range of kerosene or so-called safety or Stoddard solvents, These materials are ordinarily consid ered reasonably safe to use under ordinary ambient condi tions. When tested, however, the material proved to have a closed cup flash point of 69F. and an open cup flash point of 84F. The fire point of the material was also 84F. Such a great difference in indicated flash point could have very serious consequences. In this particular case, a floor finish is applied over a large area and, under ordinary room tem perature conditions, we would expect a flammable vapor concentration over the entire surface and, of course, an extremely severe fire hazard. We would suggest a great deal of caution in applying the flash point limits which may appear on commercially available products, especially -21- CMA 048735 when the stated flash point is in an area which would indicate reasonable safety in use. This experience indicates that spot checking at regular and probably fairly frequent intervals is advisable. CASE HISTORY NO. 1676 Fork Truck Description A fork truck operator of a product handling group was operating a high lift straddle fork truck in a rack area. After placing a pallet load in a rack, he backed up and locked the fork-lowering lever into "down" position. As he proceeded out of the room, the forks had not lowered enough to clear the 10-ft. high doorway. The vertical section of the forks struck the buckframe, causing the truck to tip backwards on top of the operator. His left heel was apparently caught under the left side of the operator's compartment adjacent to the deadman brake pedal. He worked his heel free, crawled out and started to walk to his foreman's office. A fellow operator came along on his truck and offered a ride, which the injured man declined. Then the other operator offered him the ve hicle, and the injured man took it and drove the rest of the way to the foreman's office. The injury involved deep lacerations and bone involve ment in his heel and ankle, with lost time estimated at five to six months. Preventive Measures: The locking-type lowering device will be removed from all fork trucks so equipped. This will require the operator to keep one hand on the lowering lever until the forks are completely down. It should serve as a reminder to get the forks down before moving the truck. CASE HISTORY NO. 1677 Liquids in Drums Handling and storage of chemicals in drums often presents problems in industry. Hazards of fire, explosion, and per sonal injury can be materially reduced through proper super vision, instruction, and training of personnel. A few general rules will improve overall safety where flammables, acids and caustics are stored or used: 1. Limit inside storage to the fullest practical degree, such as current operating requirements. 2. Flammables should be stored under sprinklers. 3. Ventilation should be provided for both health and safety requirements. Where dispensing is performed, mechanical ventilation should be provided for the room and at the source of emission of vapors. 4. Wherever practical, the use of glass containers for storing flammable liquids should be eliminated. For general use, flammables should be kept in approved safety cans, 5. Waste flammable liquids should be disposed of in approved Containers and removed daily. Personriel should be warned of the dangers of mixing reactive or otherwise incompatible wastes. Hence, containers should be identified. 6. Drums are not intended to be pressure vessels and should never be used as such. It is dangerous to use compressed air for transfer purposes in handling flam mable liquids. NOTE: Air-operated pumps are acceptable. 7. Metal containers should be bonded to an electrical ground. 8. Electrical equipment should be in accordance with Article 500 of the NATIONAL ELECTRICAL CODE or E.C.M.&U. Standard B31R. 9. Drums should be inspected for bulging at least weekly, and more often when exposed to sunlight or heat. If bulging occurs, the pressure should be released. Bulging may be caused by expansion of vapor space through heat absorption, by action of the chemical on the metal container or by a reaction of the contents within the container. Proper protective equipment should be worn when venting drums. Drums can also be vented automatically by devices which are used in place of the bung. These are particularly good on drums being used for dispensing. CASE HISTORY NO. 1678 "A Hell of a Way to Run an Airline" While this story comes from the airlines and by way of the Flight Safety Foundation, the lessons apply just as forcibly to all of us in industry. The story, direct from a "SPECIAL ALERT" bulletin of the Flight Safety Foun dation, is as follows: WOULD YOU BELIEVE??? That a large twin-engine piston-driven airplane was de molished in a crash-landing when it took off after being "topped off" with Jet A fuel. This, despite the fact that according to reports -- The door over the filler cap was placarded "FUEL 100 OCT MIN." The fuel truck had "JET A FUEL" and "TURBINE FUEL" on it in large letters. A flight crew member observed the fueling. The fuel ticket had "JET A" as the fuel serviced. It is not our purpose to assign a "Probable Cause." or even verify the above reports -- but magicians have known for years that people see and don't observe. It can ... and does happen in aviation. WHY NOT Color-code the filler necks and fuel truck nozzles with the color of the fuel? Make "quick disconnect" fitting for both aircraft and fuel hoses which are not interchangeable, for each grade of fuel? The same thing has probably happened in many chemical plants where liquids are put into tanks -- and the story serves to remind us of the fact that putting the wrong liquids into tanks is a sure way to disaster. ...22- 048736 CASE HISTORY NO. 1679 ned by Steam Description: Just after shutdown of the plant, an operator was about to trim the SOi gas outlet valve on a fulfurtc arid contact boiler, when hot water began to spout out of one of the boiler tubes. The operator climbed to the point where the hot water was spouting, with the intent to install a plate to divert the flow- away from the area where he and another operator were working. At this precise moment, the safety valve opened and steam blew up over his face, neck and chest. He suffered second degree bums around the face, neck and chest. Cause: 1, Taking a position in front of the safety valve outlet on the boiler. 2. Safety valve exhaust pipe was installed in a horizontal position. Preventive Measures 1. Establish safe procedures while working in proximity of steam or hot water vessels. 2. Modify the safety valve outlets to release in a safe direction. * CASE HISTORY NO. 1680 Plug -- Unused Connection Description: As slurry was being emptied from an evaporator into hold kettle, operator placed a ladder behind the kettle in order to see over the top and observe the level. In approaching the ladder, he walked near the tank and brushed against a plastic pipe plug in an unused connection, allowing hot caustic liquid to pour out onto the lower part of his right leg, inflicting second-degree bums. Cause: Inadequate pipe plug. Preventive Measures: All plastic pipe plugs in hold kettles have been replaced with metal plugs, and all connections have been checked for tightness and adequacy. CASE HISTORY NO. 1681 Epoxy Paint Description: A painter received a cornea bum of the left eye. He was using an epoxy type paint and a small particle struck his eye. The eye was immediately flushed with water before reporting for medical treatment but the next morning fkwas very irritated. Preventive Measures: Since most epoxies are irritants or sensitizers, eye protection, gloves and full skin protection are needed to avoid contact. CASE HISTORY NO. 1682 Defective Regulator Description: A Pilot Plant operator received an eye injury when dimethylamine sprayed from a leaking pressure reg ulator on a nitrogen cylinder. Evidently the solvent from the still he was pressurizing had condensed into the defective regulator. The injured was wearing safety glasses but a small amount of the DMA struck the corner of his eye. Preventive Measure: An additional valve was installed in the nitrogen line to minimize the possibility of condensate getting into the regulator. CASE HISTORY NO. 1683 Flash Fire in Drying Operation Description: An operator received bums about the face and arms when flammable solvents flashed in a large gas fired dryer. There was practically no equipment damage. Solvent laden charcoal was being reactivated as a special accommo dation for a customer. It had been believed that the amount of solvent present would not create a fire hazard. However, a possible malfunction of a bucket elevator was not taken into account but it happened. When the discharge stopped, flammable vapors built up into the explosive range. Obvi ously the safety of this drying operation had not been prop erly evaluated. The accident had potential for much more serious consequences. Preventive Measures: New processing or operations even though temporary should not be undertaken without com pletely assessing the risks involved by following established safety procedures. CASE HISTORY NO. 1684 Laboratory Glass Description: The reservoir on an automatic buret exploded. The reservoir contained sodium methylate (0.5 N in pyridine). The explosion threw flaming liquid on two lab analysts which resulted in second and third degree bums to both analysts. Also, both received cuts from flying glass. One of the men's injuries was disabling. The accident occurred while an analyst was attempting to remove the automatic buret from the reservoir which contained about 600 ml. of liquid. This liquid is a solution of sodium methylate, methanol and pyridine. The analyst had attempted several different methods of freeing the ground glass fitting, with no success. Another analyst said he had freed the connection several times in the past by passing the flame of a Fisher burner over the ground glass joint. He recommended that procedure be used again. The analyst carried the unit to a hood in the wet lab and began heating the joint with a Fisher burner. Another analyst had just walked up to the hood when suddenly the reservoir exploded throwing flaming liquid and glass fragments on both men. -23- CMA. 048737 One analyst ran down the north wall of the wet lab with his clothing in flames. Two analysts came to his aid, and within 15 seconds had extinguished the flames with a COa extinguisher. He was placed under the shower outside the lab and ice was packed on his bums. The second analyst ran down the east wall of the wet lab into the hall. The fire on his clothing had gone out. He was treated for shock, and ice was packed on his bums. Three analysts approached the fire, which was mostly contained in the hood, with CO: extinguishers. The fire was out about 30 seconds after the explosion. Both men were taken to the hospital by ambulance. The Investigating Committee commended the laboratory personnel. They reacted very quickly and efficiently in dea ling with the emergency. Cause: Unsafe method. The ground glass joint stuck. Open flame was used to free the joint and the flame ignited vapors around the hole used for the drying loop connection. The flame front flashed back into the reservoir which exploded. Preventive Measures: 1. Revise the Lab Safety Manual to specifically prohibit using open flame to loosen ground glass joints in flammable service. 2. Investigate methods to prevent ground glass joints from freezing up when used in a flammable service and set up a procedure. CASE HISTORY NO. 1685 Fatal Accident -- Vacuum Dryer Loading Description: This accident occurred during the loading of a rotating vacuum dryer with a batch of toluene-wet product material. The unit involved is a double-cone rotating vacuum dryer of about 230 cubic feet capacity. The dryer is equipped with a steam jacket and a nitrogen purge line and is normally operated with an inert atmosphere. The operator was on the second floor lowering a batch of wet filtrate into the dryer u'hicb is installed on the first floor. A 12-inch diameter loading chute extended through the floor. It appears that one drum of the material had been charged into the dryer and the operator was starting to charge a second drum when an explosion occurred either in the dryer or in the lower end of the loading chute. The force pushed the chute upward and blew the toluene-wet material out of the chute into the second floor area. Next, an explosion or flash fire occurred in the second floor area, severely burning the operator and blowing out the explosion-relieving building panels. The operator succeeded in getting under a safety show'er, but it was difficult for other employees to find hint quickly because of the black smoke from burning toluene. In spite of the use of the safety shower, the operator received third and second degree bums from which he later died. The ensuing fire was extinguished by the operation of eight sprinklers and by plant operators using U/2 inch fire hose and dry chemical extinguishers. Cause While all of the conditions surrounding this accident cannot be fully known, it is assumed that the atmosphere in the dryer was not fully inert and that ignition resulted from static electricity. The electrical bonding connections were found to be severed or disconnected after the incident. It is not known whether they were severed or disconnected before the explosion or whether this disconnection was the result of the explosion. The valve in the nitrogen purge line to the dryer was found open. Preventive Measures: This serious accident points out the susceptibility of toluene and other so-called "dry" solvents to ignition by static electricity and the necessity for maintain ing a fully inert atmosphere for such operations. Among recommendations being studied is the provision of a rotary feeder valve for the admission of material to be dried. Such a rotating valve would provide a seal for the dryer and permit maintenance of an inert atmosphere at all times. The oxygen content of such equipment will be regularly checked during the various stages of the charging operation. CASE HISTORY NO. 1686 Chloroform Exposure Description: An employee was affected by chloroform va pors while working on a granulation. The employee was released several hours after he was hospitalized, in a satisfac tory condition, but such exposures to high concentration harmful vapors are generally potentially serious. Cause: As in most accidents, several causes contributed to the over exposure. The employee failed to wear respira tory protection. He was trying to complete four batches at once instead of the normal three and working long hours. The exhaust system in the commuting booth was not properly balanced. CASE HISTORY NO. 1687 Machinery Description: An operator sustained partial amputation of three fingers when his hand was caught in a mold. When the mold was opened and the article removed, a part of the article remained in the nozzle. The operator determined that this material would not be ejected, so he opened the fix plate and tried to remove it by stroking the back of the plate. This operation is performed normally by the operator himself. On this occasion and due to the fact that another person was with him helping to make the change of the color, the operation was performed by two persons. When the operator removed the locks that secure the head of the three pins that hold the fix plate, he removed two of these locks and without coordination with his assistant. The assistant manually moved the plate when the operator removed the last lock. At this instant his fingers were caught between the pin and the column of the machine, amputating the distal phalanx of the index, middle and ring fingers of the right hand. Cause: Failure to follow procedure. It is established that only one person should do this operation, the operator of the machine himself. -24- CMA 048738 I enttve Measures: Insist that the operation of cleaning the nozzle should be performed by one person (the operator of the machine). 2. Inside the department there will be an intensification of the instruction campaign to avoid insecure acts by personnel working in this department. 3. Study and modify the equipment to eliminate the operating hazard. CASE HISTORY NO. 1688 Centrifuge Explosion Description: An operator escaped serious injury when an explosion occurred inside a centrifuge. The equipment involved is a vertical shaft, manual, hand dug, batch oper ated Tolhurst centrifuge. The machine handles a slurry of phenacetin in ethanol at about 30C. The cake is washed using ethanol. Centrifugation had been proceeding since the early shift using the department's vertical shaft Tolhurst machine. Centrifuge load no. 4 from this batch had been unloaded into the flash drier and load no. 5 was being processed. A new operator, was on his first day of training and was operating the centrifuge at this time. Material for load no. 5 had been fed into the centrifuge, the mother liquor had been wrung out, the wash had been put on and the dry spin had been completed. The centrifuge was stopped and ^^ki brought back up to the digging speed for 70 RPM. digger was lowered into the basket and was turned into the cake to start pulling the crystals down into the bottom of the basket. At this moment, the operator heard a noise like a small explosion and saw a flame come out from under the lid of the centrifuge. Almost immediately thereafter a second pop was heard, the lid of the centrifuge was blown open, and flames shot several feet into the air. The rubber flexible hose which connects the machine to the mother liquor tank was also ruptured. At this point the operator was standing right next to the machine. He immediately started to run from the area via the west exit of the department. Prior to leaving he turned and saw that the flames were not completely out of control so he grabbed a fire extinguisher, returned to the centrifuge, and put out the fire. The operator's prompt action in extinguishing the fire may well have been the main factor in preventing major injuries to personnel and losses of equipment. Cause: The basic cause of this incident is related to the design of the digging mechanism on the centrifuge. It was found that when the digger is lowered into the machine, unless a certain specific operating technique is used the plow will come in contact with the center cone of the basket. Since both the cone and the plow are made of stainless steel, there is certainly the potential here for the generation of sufficient heat through friction to provide a source of ignition for the ethanol fumes present in the unit. Upon inspection of the centrifuge center cone after the Indent, it was found that the cone was scored and that nere was evidence of metal fusion at the point of contact with the digger. Inspection of the digger showed that its lower edge had recently been ground away, removing perhaps 1/8" of metal. The blue burnish marks were still present at this point of contact when the digger was inspected in the shop. It is the conclusion of the investigating commit tee that this contact between the digger and the cone did indeed provide the source of ignition which caused this explosion and fire and should be considered the basic cause of the incident. There was one secondary cause which probably could have prevented this incident. It relates to the COi purge system used on the centrifugal. The rotameter on the COz purge system will allow 2.5 SCF per hour at 10 psig to flow into the centrifuge if it is set at full scale. While the operating instructions do not specify the setting, the operators described their normal operating setting as about 1.0 SCF per hour. There are no special instructions concern ing the length of the purge time prior to feeding material after the machine has been opened. No calculations or measurements of concentration were made by the com mittee. However, it appears that the purge system is signifi cantly undersized. This machine was installed in the department about June, 1968. At that time it was a used machine. Since that date the digging mechanism has been altered several times. The most recent modification, which was a repositioning of the plow, was completed on 10/3/69. As a result of these altera tions, the situation which existed at the time of the fire came to be the accepted condition for that machine. Specifically, when the digger is run down into the basket, the plow will rub the center cone of the basket when it is turned out of the way. These alterations should not have been authorized. This centrifugal has been part of the plant's routine inspec tion program. The most recent inspection was carried out March 6, 1970. In spite of the fact that the condition noted above existed, it was not observed. It was the opinion of the committee that the control over that maintenance pro gram is not sufficiently tight and that possibly the respon sibilities for centrifuge maintenance have not been ade quately defined. Preventive Measures: 1. Redesign and install the digging mechanism so that metal on metal contact is not possible under any operating conditions. Provide appropriate locking devices to prevent the digger from accidentally lower ing itself into the basket. Repair or modify the locking device which prevents the digger from accidentally cutting into the cake. 2. Re-evaluate the CO2 purge requirements for this sys tem. Make recommendations as to design and operat ing conditions for this purge system and install equip ment as necessary. 3. Review the centrifuge maintenance program with respect to responsibility for the equipment and control over the maintenance operation, 4. Inspect all centrifuges of this type (vertical shaft, man ually operated) to determine whether contact between the digging mechanism and the basket is possible. Take appropriate action. CASE HISTORY NO. 1689 Hot Asphalt Description: A one gallon can of asphalt was being heated on a hot plate to secure a sample of material for viscosity -25-- CMA 048739 figure. While the material wass being heated, a technician was attempting to break the surface and stir up the asphalt. The surface collapsed, splashing hot asphalt onto the right hand, particularly the palm, lower wrist, middle, ring and little finger. The procedure must be evaluated as unsafe because of the element of risk present. Investigation revealed that the injured, although associated with this project was not the technician actually running this experiment. He failed to anticipate the result of his action in attempting to submerge the unmelted surface crust and also failed to protect his hand by wearing a glove. The employee who was running the experiment, did not exercise control of his experiment sufficiently to prevent the incident. Cause: Unsafe procedure. Preventive Mensures: 1. Since normal procedure is to heat the asphalt to fluid condition in an oven preset to the desired temperature, this procedure must be regarded as standard. The hot plate method of heating a solid mass of asphalt must be discontinued. Small sample runs may be made by removal of representative samples with a hot blade such as a calrod unit. 2. All supervisory personnel are to review techniques for handling hot materials with their people. Hand protection must be used when the possibility of bums can occur. This should be interpreted to mean while handling hot objects as well as while working in proximity to hot materials. CASE HISTORY NO. 1690 Acid Transfer Description: Dilute acetic acid (approx. 25%) was being transferred from a storage tank to a slurry vessel, and the injured went to close a valve on the transfer line. Instead of operating the valve from the floor, he stood on a 4" pipe which runs at a height of about 12" above the floor. He slipped and fell, suffering injuries to his ribs and ankle. There are four tanks on an outside roof which forms a floor for them. Their discharge lines run at heights of about 6-12" above the level of the floor. An approach platform extending the length of the tanks, and about 3' above the floor, provides access to the valves via a metal staircase at either end. In order to operate some of the valves it may be necessary to step over one or more of the discharge lines. The injured states that as a short cut he stepped over the railings on the access platform and onto the pipe. The Committee notes from the appearance of the pipes that this must be done frequently by employees. Cause: 1. Basic -- Adopting an unsafe method of work. 2. Contributory -- A rather awkward approach to the valves, making the unsafe way more attractive. Preventive Measure: Lengthen the valve spindles so that they can be operated from the access platform. CASE HISTORY NO. 1691 Stirrer Fails to Operate Description: At ahout 3:35 p.m. the reaction mixture in a tank erupted, releasing liquor and an ammonia cloud into the work area. The operator at the tank was struck by the Hying liquor and exposed to the ammonia vapor. The operator was taken to the hospital where he remains for treatment. His condition is good. The ammonia cloud was in its flammable range and ignited under the roof. This activated the sprinkler system. Cause: Investigation of the accident that night revealed the primary cause: the entire charge of ammonia solution for the neutralization reaction was introduced into the reactor without the stirrer operating. When it was realized that no agitation was taking place, the stirrer was started, causing an immediate massive reaction which boiled out the process liquor and released the ammonia gas. Preventive Measures: Acid-base neutralization is carried out a number of times each day at numerous locations throughout the plant. Therefore, the potential for an accident such as occurred above, is great. To carry out neutralization reactions safely, there are a few basic practices which each operator must keep fore most in his mind: 1. The neutralization must not be started unless the stirrer is on and operating satisfactorily. 2. The rate of addition of neutralizing solution must not exceed that called for in the master process. 3. Throughout the course of the neutralization, vessel checks must be made to be sure that the stirrer is indeed providing agitation to the tank. 4. If, at any time, it is found that the neutralization has proceeded without agitation, the addition of the acid or base must be stopped immediately and the situation promptly called to the foreman's attention. No further processing of the reaction should occur until plans have been worked out to handle the poten tial mass reaction and the necessary safety equipment has been brought to the scene and put in use. 5. The condition of the agitation system and neutraliza tion reactors must be checked regularly to assure that agitator blades are in good repair, properly fastened to the agitator shafts, and that agitators are operating at their proper speed. 6. These precautions must be exercised as appropriate even if stirrer operation is signalled by lights, or its failure by an audible alarm, or the addition line valve is interlocked to stirrer operation. The best safety device is still a trained, alert operator. CASE HISTORY NO. 1692 Grinding Description. A machinist was setting up a tool post grinder on his lathe. He switched the power on the grinder and the abrasive wheel suddenly exploded with a piece of the wheel striking him on the forehead, resulting in a severe frontal skull fracture. - 26- CMA 048740 The tool post grinder attachment for the lathe takes up " diameter by Vi'- abrasive wheel, and a metal cup is provided to cover this size wheel. Its rate of speed is 9,000 rpm. For this operation, the grinder was equipped with a used stone, approximately 5'/a'' in diameter by V2" thick. This stone, when new, was 6" in diameter with a rate of speed of 4.600 rpm, A set of pulleys are provided to adjust to the proper rate of speed of the wheel. The pulleys in use at the time of the accident were adjusted for a speed of 14,600 rpm or 10,000 rprn's more than the rated maximum speed of the grindstone in use. The cup guard was not in place and the employee w'as not wearing a face shield. Cause: 1. Use of improper grinding wheel for the speed of the grinder. 2. Cup guard was not in the proper position. 3. Operator was not using a full face shield as called for in safety regulations. Preventive Measures: 1. Review accident causes with all personnel and present revised job safety procedure. 2. Review procedures for handling and using grind stones, including proper storage and use of correct pulleys and pulley adjustments for various size stones. 3. Require the use of full face shields when operating grinding wheels. CASE HISTORY NO. 1693 Laboratory Bottle Peroxide Hazard Description: The possibility of formation of unstable perox ides when certain chemicals are kept in storage has again been brought to attention by a minor explosion. In this incident when a man took a sample bottle of vinylidene chloride from the refrigerator and opened it, he found a small white deposit on the bottom of the glass stopper. In trying to remove this deposit, it exploded causing a very minor injury. Following this, another man removed a glass stopper from another similar bottle and this time found a large deposit. This was taken very gently to a burning area and gingerly tossed into the burning pit. The peroxide on the stopper exploded violently as it entered hot gases. Preventive Measures The following label has now been developed for peroxide forming agents and materials for which this label is required have been listed. WARNING PEROXIDE FORMER One year after receiving Destroy Contents One month after opening Date Received Date Opened Issued To __________ ________ (a red background is recommended) Use of this label is recommended in all laboratories where any chemical materials are used which do have this peroxide forming tendency. PEROXIDE FORMING CHEMICALS (Partial Listing) ^ Acetal *Allyl Ether Allyl Ethyl Ether ^Allyl Phenyl Ether *iso-Amyl Benzyl Ether n-Amyl Ether p-n-Amyloxybenzoyl Chloride *Benzyl n-Butyl Ether *Benzyl Ether * Benzyl Ethyl Ether Benzyl Methyl Ether *Benzyl 1-Naphthyl Ether Bis (2-n-butoxyethyl) Phthalate Bis (4-chlorobutyl) Ether 1.2-Bis (2-chloroethoxy) Ethane Bis (2-chloroethyl) Ether Bis (chloromethyl) Ether Bis (2-ethoxyethyl) Ether Bis (2-ethoxyethyl) Phthalate Bis (2-methoxyethyl) Adipate Bis (2-ethoxyethyl) Adipate Bis (2-(2-methoxyethoxy) ethyl) Ether Bis (2-methoxyethyl) Carbonate Bis (2-methoxyethyl) Ether Bis (2-methoxyethyl) Phthalate Bis (2-phenoxyethyl) Ether 2-Bromoethyl Ethyl Ether beta-Bromophenetole 0-Bromophenetole p-Bromophenetole 3-Bromopropyl Phenyl Ether t-Butyl Ethyl Ether t-Butyl Methyl Ether n-Butyl Phenyl Ether n-Butyl Vinyl Ether *Chloroacetaldehyde Diethylacetal *2-Chlorobutadiene 1- (2-chloroethoxy )-2-phenoxyethane Chloromethyl Methyl Ether beta-Chlorophenetole o-Chlorophenetole p-Chlorophenetole *Cydohexene *Cyclooctene *Decalin *p-Dibenzyloxybenzene * 1,2-Dibenzyloxyethane p-Di-n-Butoxybenzene 1.2-Dichloroethyl Ethyl Ether 2,4-Dichlorophenetole m-Diethoxybenzene o-Diethoxybenzene p-Diethoxybenzene 1.2- Diethoxyethane *Diethoxymethane 2.2- Diethoxypropane *Diethyl Ether -27 -- CI4A 048741 Diethyl Ethoxymethylenemalonate '`Diethyl Fumarate * Diisopropyl Ether +1,1-Dimethoxyethane 1.2-Dimethoxyethane *Dimethoxy methane *2.2-Dimethoxypropane *Dioxane * 1.3 Dioxepane 2,4-Dinurophenetole *Di-n-propoxy methane 1.2-Epoxy-3-phenoxy propane * 1,2-Epoxy-3-isopropoxypropane p-Ethoxyacetophcnone 2-(2-Ethoxvethoxy) ethyl Acetate 2-Ethoxyethyl Acetate 2-EthoxyethyI o-Benzoylbenzoate !-Ethoxynaphthalene o-Ethoxyphenyl Isocyanate p-Ethoxyphenyl Isocyanate 3-Ethoxypropionitrile Ethyl Ether Ethyl beta-Ethoxypropionate Ethyl Vinyl Ether n-Hexyl Ether o-Iodophenetole p-Iodophenetole Isoamyl Ether Isobutyl Vinyl Ether *lsophorone *beta-Isopropoxypropionitrile *Isopropyl Ether Isopropyl 2,4,5-Trichlorophenoxyacetate 3-Methoxy-1-butyl Acetate 2-Methoxyethyl Acetate beta-Methoxypropionitrile Methyl p-n-Amyloxybenzoate n-MeAylphenetole m-Nitrophenetole Oxybis (2-ethyl acetate) Oxybis (2-ethyl benzoate) beta-beta-Qxydipropionitrile Phenoxyacetyl Chloride alpha-Phenoxypropionvl Chloride p-Phenylphenetole Phenyl o-Propyl Ether n-Propyl Ether *n-Propyl Isopropyl Ether *Tetrahydrofuran +Tetralin Triethylene Glycol Diacetate Triethylene Glycol Dipropionate * 1,3,3-Trimethoxypropene *VinyIidene Chloride *Isoamyl Benzyl Ether ^Denotes those chemicals which form peroxide with ease CASE HISTORY NO. 1694 Employee Catapulted Off Tank Truck Trailer Description: Employee was standing on 10" hinged loading hatch of a carrier's tank truck trailer prior to loading 50% caustic soda. The single wing nut was difficult to open. He requested carrier driver to check for air pressure on trailer. Two drivers confirmed there was no pressure on trailer. Employee turned wing nut several times with no apparent release of air. When he kicked bolt off. the hatch flew open and catapulted him into the air and off the end of the truck trailer down to the concrete floor. Employee sustained a compound fracture to both bones of lower left leg. Cause: Carrier failed to release air pressure from trailer after unloading. One of the three valves is closed when the handle is in line with the pipe. The other two are open in this position. Pressure gauge on carrier's trailer may have been faulty; did not move when 5 psig applied to trailer during investigation. Preventive Measures: 1. Review procedures to determine actions necessary to prevent recurrence. 2. Consider requiring carriers to open hatches before moving under loading spout, 3. Improve guarding at loading rack to prevent falls due to slips or being "startled." CASE HISTORY NO. 1695 Sustains Chemical Durn to Eye Description: Operator was sprayed in the face and eyes with liquid ammonia from a defective vent hose on a vendor tank truck. He had unloaded the truck and was in the process of blocking and bleeding the 2" unloading line. A rubber hose section of the vent line ruptured and sprayed ammonia with sufficient force (approximately 150 psig) to loosen the operator's chemical goggles. He received a chemical burn to his left eye. Cause: Common rubber vent hose was not adequate for ammonia service. Preventive Measures: 1. Vendor will replace vent hose with stainless steel tubing. 2. Ammonia will be piped into this plant. 3. Operators will be instructed and trained to detect equipment defects. CASE HISTORY NO. 1696 Incinerator Explosion Description: A minor explosion occurred in the waste incinerator due to improperly charging a reactive material into the primary burning chamber. While the results of this particular incident did not result in injury to operators or severe damage to equipment, it is appreciated that a very serious potential exists if a reactive material is loaded into the wrong part of the incinerator or more especially if large amounts are loaded at one time. This incinerator consists of a vertical cylindrical primary burning chamber with a sliding horizontal gate under a -28 CMA 048742 hopper at the top and a conical rotating grate at the bottom, ^fc^inary combustibles such as wood and paper are loaded the incinerator through the hopper by means of a clam shell bucket, remotely controlled. Products of combustion from the primary combustion chamber pass through a second combustion chamber, then pass through a spray cooling chamber. Electrical interlocks are provided to prevent opera tion of flammable liquid pumps supplying oil burners dis charging into the primary combustion chamber until the chamber has reached a temperature in excess of 1200F so that waste flammable liquids introduced through the oil burners will be immediately ignited. This chamber is also provided with a fire door and dump chute remotely controlled for admittance of reactive materials or other chemicals which may be destroyed through the heat and secondary combus tion air in this chamber. In this particular incident tailings from a process for manu facturing a diazido compound had been sent to the incinerator for burning. It is normal practice with reactive materials to package it in small containers properly labeled which can then be charged into the primary combustion chamber. For some reason this material was delivered to the incinerator in three fiber drums holding about 50 pounds each Ft has been stated that these drums had been properly tagged. Some time later operators assumed that these drums contained non-hazardous material and charged two of them through the hopper and sliding gate directly into the primary burning chamber. An explosion resulted which blew open ventilation doors and inspection ports and liberated enough heat to activate three sprinkler heads at the charging level. fTall clumps of dust were ignited on the steelwork. attse: Several standard safety practices were not followed in this incident. The material should have been divided into small bags not over 10 pounds each. Identification tags should not be removed until the material is actually ready for dumping into the incinerator. CASE HISTORY NO. 1697 Acid from "Empty" Line Description: Two mechanics had finished repacking a pump when they were advised by operator that there u'as slight weeping in one of the valves that had been drained prior to work on pump. Without putting acid suits back on (violation of plant safety rule), and without further evalua tion of the piping system which was still locked and tagged at valves preparatory to pump repair, they removed bolts on valve bonnet. The bonnet flew off suddenly, spraying one mechanic with mixed acid on back of head, shoulders, and right forearm; other mechanic received only slight spray. Cause: Line in question was on slight angle from horizontal and was steam traced to prevent freezing. Since steam had een on during half-hour of pump repair, acid at low spot as under pressure in closed-pipe system. Preventive Measures: All employees advised there must be strict adherence to all rules. CASE HISTORY NO. 1698 Failure to Use Protective Equipment Description: In his bare right hand, operator was carrying an open stainless steel cup (by its insulated handle) filled with molten sample (250C), and in his left hand a closed 8-ounce glass jar (wrapped in cloth) containing another hot sample. When the glass jar began to slip from his grasp, he attempted to stop the movement with the open cup. and spilled the sample over his hands. Loss of time became necessary for skin grafting. Cause: Failure to use protective equipment. Preventive Measures: Reemphasis has been given to the existing rules requiring operators to wear rubber gloves and use sample carrier. CASE HISTORY NO. 1699 Changed Process -- Instructions Unchanged Description. Operator sustained second and third degree burns of arms, legs, abdomen, and face (eyes saved from serious burns by side-shield safety glasses underneath face shield) when splashed with hot (280DC) tarry material as he was disconnecting portable tank. He had closed 1" valve in feed line from distillation column, and was breaking quick connection when incident occurred. Cause: Relatively new process was being run in equipment designed for another product; proper attention had not been given to altering operation instructions and training operators in differences between two products. Preventive Measures: Revised operating procedures have been prepared; valves have been installed at ends of fill and vent lines directly above disconnect couplings; rodding valve has been redesigned to prevent possibility of material blowing on operator; and additional protective equipment is being considered. CASE HISTORY NO. 1700 Explosion When Welding Water Line Description: A welder was to install a steel coupling on a chilled water system. The procedure was to drain the w'ater from the system, bum a hole in the 6" closed water line to the heat exchanger and weld the coupling in place. The hole was made, coupling was positioned for welding and the are was struck. At this instant, an explosion occurred, blowing the one and one-half pound coupling across the room. Fortunately no one was in the path of this missile. An explosimeter was used, and the atmosphere in this system was found to be above the lower explosive limit. Air samples analysed by the Industrial Laboratory disclosed an accumulation of hydrogen m the line. The line was flushed out and purged with nitrogen before the system was found to be safe to weld. -29- CMA. 048743 Cause: It has not yet been determined, for certain, what caused the accumulation of hydrogen. Possibilities are that the water sitting unused during the winter months, in combi nation with the water treatment agent, may have acidified and reacted with the metal pipe liberating hydrogen. Another cause may have been the decomposition of the water treat ment agent itself Investigation is still continuing on the causes CASE HISTORY NO. 1701 Ambulance Incident Description: An ambulance was responding to an emergency call. This ambulance was of typical design with two doors on the right side, one for the driver's seat and a large one for admission of a patient. The large door was hinged at the rear It should be noted that when purchased, a front hinged door was available as an option -- perhaps at higher cost. Response to the emergency call was made at high speed, estimated at 70 to 75 miles an hour. The attendant was preparing oxygen and suction equipment when the door flew open and the attendant was thrown or pulled out, result ing in fatal injuries. Cause: The lessons are clear -- the hazard of a rear hinged side door is evident. Also evident are the hazards in high speed in ambulance operations. Of further significance is a door interlock which was not functioning properly. CASE HISTORY NO. 1702 "Empty Drums" Description: An employee received surprisingly severe injury when he used an empty drum to receive oil from a turbine during an oil change. Procedures which had been set up to prevent use of "empty" drums for any purpose and to require the use of clean, reconditioned drums had been circumvented, in part due to temporary relocation of a roadway through the "empty" drums storage area. When the bung w'as removed, the employee immediately suffered severe eye bums and intense lung irritation so that he was unable to breathe although he struggled desperately to do so. He was quickly taken to the Medical Department and treated with oxygen and his eyes flushed. The primary concern in emergency treatment was his severe breathing difficulty. He was transferred to a hospital where he later developed pneumonia and received treatment for severe eye bums. He was in critical condition for several days. Cause: The "empty" drum had contained diethylamine, well known as a severe irritant. However, this incident indicates that diethylamine is even more severe in its immediate effects than had been known, This should serve as a strong warning in respect to the hazards of so-called "empty" drams and the particularly severe hazard of diethylamine. Preventive Measure: Drum handling procedures in all our chemical plants are being reviewed and strengthened. CASE HISTORY NO. 1703 Chemical and Thermal Burns Description: An employee was assisting in performing an industrial cleaning job on a boiler for a customer. The boiler had previously been filled with hot water and had been drained through the Marlowe pump with no prob lems or leaks. The boiler was then filled with acid solution and, as they were adjusting the acid strength and were drain ing some hot acid through the Marlowe pump, the hose slipped off the fitting and acid flooded the area in which the employee was standing. Cause: 1. Hose clamps were loose. At 150, the hose evidently softened sufficiently to allow it to slip off of serrated fitting. 2. No checking clamps after hot fluids were in system. Preventive Measures: 1. Hose clamps will be double-checked before and dur ing treatments. 2. The possibility of using steel connections in place of rubber hose will be investigated. CASE HISTORY NO. 1704 Sprayed with Hot Caustic Description: An employee was assisting a second man in stopping a condensate leak. He was working from a scaffold in pipe rack (10' elevation). As he stepped from the scaffold to a pipe, his foot inadvertently struck the handle of a 1" ball valve located on top of the pipe. The employee was sprayed with hot caustic (509f). The employee sustained caustic bums to the trunk of his body and to his buttocks: in addition, he fractured his ankle when he jumped from the scaffold to ground level. Cause: 1. Ball valve was not plugged. 2. Employee was working in unsafe position outside scaffolding, and was inattentive to his surroundings. Preventive Measures: All ball valves were plugged, and where possible, T-type handles will be used in place of bar-type handles. CASE HISTORY NO. 1705 Tank Car Unloading Description: A Utility Operator suffered severe bums on head, arms, and back when hot wax erupted from a tank car he was preparing to unload. High pressure steam through the interna! coils of the car had been used to heat the wax to 115C. The car was -30- CMA 048744 connected to two unloading pumps, which were running. e unloading lines, which are cleared after each use with Ram. are traced and insulated. The internal, spring loaded unloading valve of the car was closed. As the employee opened the external valve under the car. hot wax erupted from the dome and ran down the sides. Can sc Investigation indicated that residual material in the unloading line, probably condensate, developed pressure as the lines were heated. The pressure was contained by a plug in the line and the valve under the car. Opening of the valve under the car allowed the pressure to lift the spring loaded valve and surge into the car. Preventive Measures: Corrective steps, too numerous to list here, include installation of bleed fittings on lines, exten sion handles on valves, use of low pressure steam, tempera ture control, and relocation of valves and equipment. They provide for reduction of potential combined with removal of personnel from the exposure. CASE HISTORY NO. 1706 Tank Car Operator Burned with Phenol Description: An operator was checking out a phenol tank car loading line prior to loading a tank car. The line was blown with air to verify that it was open. The air blowing operation was repeated and the system was set to pump icnol to the tank car. After phenol was valved into the |e, the operator noticed there was no flow of material, e thought that perhaps a "quick-closing" valve might have shut; he changed the position of the valve and repeated the steps to flow phenol to the tank car. No flow was noted and he was unable to reposition the valve to its original position because it had apparently stuck. A mechanic was requested to help free the valve after the operator had vented the loading line on both sides of the emergency valve. The mechanic and operator climbed onto the roof of the tank car loading station to gain access to the valve. The operator removed the bonnet of the valve and some phenol "bubbled" out of the top. He attempted to work the valve lever with his foot while keeping his body and face away from the top of the valve. He felt the lever move and bent over the top of the valve to see w hat happened. At this instant, trapped phenol sprayed from the open valve top hitting him on the face, neck, and left arm The operator was guided to a safety shower by the mechanic and washed. Since the safety shower did not have an emergency alarm pull ring, the mechanic telephoned for assistance after an initial washing period. The operator suffered phenol burns on his face, neck, and left arm. Cause The operator did not normally perform the tankerman's job; his assignment was temporary and he was not ota 11 y familiar with all facets of the tank car loading deration. In fact, the design of the emergency valve made "opening of the valve difficult when under pressure. The regular phenol unit tankermen were aware of this fact. The emergency valve is not normally used during tank car loading. Its purpose is for quick shutoff of the tank car line in event of an abnormality. The following conclusions were reached by the Accident Review Board: 1. The operator and mechanic climbed to the platform above the valve rather than using a ladder or scatfold to reach the valve. Therefore, the operator was positioned above the valve rather than to the side. 2 The operator did not recognize the hazardous nature of his actions. This was due partly because of a tempo rary job assignment and because he was rushing to complete the tank car loading job. 3. The operator had removed the top of his rubber suit. The burns on his left arm would have been prevented if he had worn the rubber jacket. 4. The safety shower used for washing the operator did not have an emergency alarm pull ring. The other safety shower and both loading platforms were equip ped with alarms. Neither the mechanic nor the operator used the plant emergency alarm system to indicate a need for assistance; alarms were by-passed en route to the nearest telephone. Preventive Measures: The following recommendations were offered: 1. Provide adequate marking and position indication on the emergency valve so that the purpose and position of the valve are identical. 2. Enlarge dispensary shower facilities to facilitate wash ing a person who has been sprayed with a hazardous chemical. 3. Install an alarm pull in the east phenol tank car loading area safety shower. 4. Emphasize through safety bulletins and other communication media the importance of using the plant emergency alarm system to call for assistance. 5. Expand all job safety analysis write-ups to include instructions for abnormal situations. 6. Revise departmental safety rules to require wearing of face shields when opening lines or vessels where phenol may be present. 7. Develop a hazardous work permit to cover pipeline opening and other hazardous jobs where dangerous chemicals may be present. CASE HISTORY NO. 1707 Another Plugged Sample Line Description: An employee was taking a sample from a pro cess transfer line. Material frozen in the line prevented him from obtaining a sufficient quantity of sample. He applied nitrogen pressure to a valved off section of the transfer line leading to the reactor in an attempt to relieve the plug. He then closed the transfer line valve, shut off the Ns pres sure, and opened the sample port. At this time a plug of the frozen material blew out, splashing him on the face, eyes and right side of body. Cause: 1. Employee did not check reactor temperature to deter mine if material was hot enough to flow. -31- CMA 048745 2. Lack of adequate sample taking procedures which would have specified proper reactor temperature for flow of material. 3. Employee lifted protective plastic film shield around the sample port and glass receiver to check quantity of sample in receiver. 4. The 4' section of sample line was not steam traced nor insulated. Need for tracing and insulation had not been determined. 5. Adequate eye protection was not being worn. Protective Measures: 1. Job planning will include the establishment and communication to employees of safe procedures for i non-routine jobs. 2. Rules regarding the wearing of protective equipment will be clarified. 3. Checkout procedures for equipment modifications will include a specific review for potential hazards. 4. The location and use of eye baths, safety showers and aid to co-workers in emergencies will be reviewed. CASE HISTORY NO, 1708 Monochloroacetic Acid Skin Contact Fatality Until recently, monochloroacetic acid has been consid ered corrosive to the skin and the usual precautions for handling corrosive materials have been recommended. In 1969 an employee spilled molten monochloroacetic acid on approximately 10 percent of his skin surface. Despite the prompt and prolonged washing of the skin with water within about one minute, the individual developed toxic symptoms and died approximately ten hours after exposure. As a consequence of this accident, more extensive toxicological studies have been conducted using experi mental animals. Liquid MCA (molten MCA) was applied to the skin of rabbits over varying proportions of the body surface. It was found that the acute dermal toxicity was a function of the applied dose, contact time, and the exposed body surface. The most significant fact learned was that skin exposure covering more than 5 percent of the body surface was fatal even when washed off after one minute. Using flaked MCA, the acute dermal LDso in rabbits was found to be 178 mg/kg. MCA is slightly less toxic in the flake form than molten MCA, but still very toxic. It has been a standard recommendation that SKIN CON TACT WITH MONOCHLOROACETIC ACID MUST BE AVOIDED because of its corrosive nature. In light of the recent accident and animal toxicity studies, this recom mendation is emphasized because of its potential systemic toxic effects which may be fatal if a significant area of the skin is involved. CASE HISTORY NO. 1709 Caustic Leak Into Drainage Ditch Description: While mechanic was making furnace repairs, he lost his balance and stepped into drainage ditch that contained about 2" of 12% caustic solution that entered his shoe through a slit along the sole line, resulting in thirddegree bum to his left foot (not discovered until some six hours after exposure). The caustic solution in ditch was caused by a leaking pump and overflow from caustic blend tank. Cause: Not seeking medical attention after exposure; open drainage ditch. Preventive Measures: Drainage ditch to be covered in fur nace area. CASE HISTORY NO. 1710 Fatal Exposure -- Aqueous Hydrogen Cyanide Description: A mechanic was removing a storage tank valve bonnet for repairs when a stream of aqueous hydrogen cyanide (6 to 8% solution) splashed on his left side. He left the spill area and was found unconscious about 180 feet from the spill. Death occurred three days later. Cause: Investigation revealed that necessary safety proce dures and prescribed safety equipment (acid suit) were not used. Preventive Measures: Extensive re-emphasis has been placed on the need for strict adherence to standard safety procedures. CASE HISTORY NO. 1711 Fork Lift Accident -- Trailer Wheels Not Chocked Description: The tankerman was relatively new and inex perienced in the operations performed at this particular ship ping building where "dropped" trailers are loaded as a matter of routine. He had completed loading one box trailer. Before starting to load a second trailer he failed to follow the procedure for assuring that the trailer wheels were chocked, that the lock-down chain was attached, and that the support jacks were in place. As he started into the trailer with a fork lift loaded with 2500 pounds of material, the trailer moved forward and the front end tipped up. As the trailer moved, the fork lift and load fell onto the dock pad between the trailer and loading dock. Fortunately, the tankerman was able to jump free of the fork lift onto the loading dock and was unhurt. Cause: The trailer wheels were not properly checked and the air brake on the trailer either had not been properly applied or air pressure had bled-off in the interim period. The tandem axle on the trailer was in a forward position rather than in the full rear position as specified for dropped trailers. In addition, the lock-down chain was not attached and the jacks were not in place. The tankerman involved failed to check out the security of the trailer before starting into it with a loaded fork lift. Preventive Measures: As stipulated in the specific instruc tions from the Carrier Control Department, the driver -32- CMA. 048746 delivering the trailer should have securely chocked the heels before dropping the trailer and the tandem axle should rve been left in the full rear position. Although the tankerman recognized that lock-down chains and support jacks were applied to dropped trailers, he was unfamiliar with the operations in a building where trailers are dropped and locked down as a matter of routine, and he overlooked the check-out procedure. It is possible that sufficient emphasis had not been placed on the required dropped-trailer procedure in the training of new employees. The recommendations offered by the investigating com mittee were: 1. A copy of this incident investigation would be for warded to the Carrier Control Department requesting that they again contact the local carriers regarding our requirements for chocking and tandem ad justments on all dropped trailers. 2. A letter would be written and distributed to all ship ping personnel involved in the loading of trailers. This letter would stress the need for observing all associated rules and would indicate the possible use of disciplinary action to enforce these rules. 3. Signs indicating the required check-out procedure for dropped trailers would be prepared and posted in con spicuous locations in all shipping buildings. 4. The development of the formal tankerman training program would be expedited and would be reviewed to insure the inclusion of procedures related to fork-lift and trailer-loading procedures. CASE HISTORY NO. 1712 Potassium Hydroxide Exposure Description: Employee received a severe chemical bum, requiring skin graft, on his right ankle from exposure to potassium hydroxide. The caustic splashed on his sock from a dramvalve while he was attempting to clean a plugged line. Employee was not aware of the exposure until several hours later when he removed his socks and discovered the injury. Cause: 1. Process line was plugged. 2. Failure of employee to use proper protective equip ment w hile performing work of a potentially hazard ous nature. Line was known to contain potassium hydroxide. Preventive Measure. Adequate protective equipment will be used for non-repetitive, unexpected, potentially hazard ous jobs of this nature. CASE HISTORY NO. 1713 ^atal Hydroblast -- Peroxide Formation Description: A horizontal steel tank about 8 feet in diameter and 20 feet long was being cleaned by hydroblasting, which is simply the use of a water jet at very high pressure. A manhole in the end of the tank was opened up at tests made for explosive vapor. All pipe connections to the tank had been properly disconnected or blanked off. A 1/2-inch hose line of nitrogen at 10 psi was connected into the tank Operators started cleaning the tank interior with a hydro blast jet after which work was stopped for about 30 minutes. On resuming work an explosion occurred when the operator opened the valve on the hydroblast line. Cause: The explosion inside the tank blew the operator about 30 feet horizontally up against another tank and was instantly fatal. The tank had contained some rust and some polymer residue which had to be cleaned out every few months The operation had been performed without trouble over a period of nine years. While there is no definite knowledge in regard to the source of flammable material, it is believed that some flam mable liquid may have trapped in the residue and was released in the first cleaning period. It is known that high velocity water sprays do produce static electrical charges. The ignition is believed to be due to static discharge. It has also been pointed out that peroxide formation in tanks which have contained active monomers is a very real possibility. In some cases the peroxide accumulation may be great enough to create a real explosion by itself in addition to firing any accumulation of vapors. Preventive Measures: Whenever a tank has contained a material which is subject to peroxide formation, the sludge in the tank should be checked for peroxides before active cleaning procedures are undertaken. A particularly hazard ous situation would result if peroxides were trapped on the tank walls by a coating of polymer material. CASE HISTORY NO. 1714 Fatality Using Corroded Fire Extinguisher Description: Pressurized fire extinguishers can be hazard ous, particularly when they are allowed to deteriorate in areas where there are corrosive vapors. Recently a 20 lb. dry chemical extinguisher activated by a carbon dioxide cartridge exploded while an assistant fire marshall was demonstrating its operation to an employee group. Cause: The extinguisher had a badly corroded base from exposure to hydrogen sulfide and other corrosives. It had been taken out of service and as eustomery in many plants, was to be used for demonstration purposes before final dis posal. When the CO2 pressure was released, the bottom of the extinguisher blew out forcing the remainder in the face of the man who was fatally injured. Preventive Measure: Damaged or corroded extinguishers should be handled with care, deactivated and junked. CASE HISTORY NO. 1715 Power Tool Description: This accident happened as a man was preparing to polish a floor. Leaving part of the power cord still looped -33- CMA 048747 over the handle of the buffer, the man plugged the cord into a nearby outlet. He then installed the brush on the buffer. In so doing, the cord apparently became caught between the brush and the buffer housing. As he lowered the buffer onto a brush pad, the power cord was pulled against the starting switch handle which is just below the hand grip. This started the buffer, which began winding the cord around the brush. The man's arm was caught so firmly betw-een the cord and the handle that he was unable to release the switch or to unplug the cord A fellow employee responded to his call and pulled the power cord from the outlet, but not before the man's arm was fractured. Preventive Measures: This accident indicates a hazard that may be present with many power operated portable tools. In this case a bracket is being provided so that the cord need not be looped over the handles near the switch. All power tools should be checked to make sure that there is no possibility of the operator's arms being wound up in the cord, either by the cord striking the switch, as in this case, or by some other operation which could cause the cord to become wound up before the operator could release the switch. This is possible when a "right angle attachment" is used with a portable electric drill. For example, if the drill snags, the operator can get "wound up" either in the cord or in his own arms almost instantly. Such devices should be used with great caution and only on low powered devices. CASE HISTORY NO. 1716 Dry Radioactive Waste Unloading Incident Description: When a cask load of canned waste was dumped into an underground caisson, radioactive dust escaped, con taminating the cask, its truck, the personnel, and the imme diate ground area. The personnel, cask and truck were decontaminated and the contaminated earth was buried in place. The accident was costly and ways to prevent recur rence were investigated. In the existing procedure, double-friction lid paint cans, 6.6" in diameter, are filled with highly radioactive dry waste, using single-arm remote manipulators. The loaded cans are transported to the burial ground in a 5-ton transfer cask, which is sealed during movement. The cask is hori zontal when loaded, and at the burial ground is raised to a vertical position with the lower end of the cask over the caisson chute. The door of the cask is opened, allowing the cans to fall into the caisson. On the day of the accident, radiation levels near the cask rose but did not subside as they usually do when all cans have dropped into the caisson. Follow-up surveys revealed personnel, cask, chute, and ground contamination. Cause: At some time during the hauling or dumping of the cask, a can lid had come off, allowing finely divided radioactive waste to spread outside the caisson when the cask was dumped. The spread was aggravated by a high wind. Preventive Measures: A solution to the problem of acciden tal opening of a double-friction lid was found to be a triple grip paint can clip purchasable at approximately lc each. The clips are positive securing devices and can be seated with a light tap. The lids with the clips preinstalled can be easily used to seal the cans even when using only singlearm remote manipulators. U.S. Atomic Energy Commission Case History CASE HISTORY NO. 1717 Gas Chromatograph Oven Explosion Description: An F & M Model 402 Gas Chromatograph oven was badly damaged by an explosion inside the oven. The explosion was caused by inadvertent introduction of hydrogen into the oven; the elapsed time between intro duction and explosion being approximately 10 seconds. The force of the explosion was sufficient to blow the oven door out of its mounting; this struck the operator and both were propelled approximately six feet from the instrument. Apart from bruising, the explosion did not cause injury. The F & M Model 402 gas chromatograph is a dual column temperature programmed instrument with dual flame ionization detectors. The oven unit is designed for U-bend glass columns and is floor mounted. The column outlets enter the flame ionization detector manifolds where the col umn effluent (usually nitrogen or helium) is mixed with hydrogen before being burned at the detector jet. The flame ionization detectors are mounted on top of the oven but air, hydrogen and eluting gas are introduced at the base of the detector which is partly inside the oven. Hydrogen is delivered to each of the flame ionization detector manifolds from needle valves and flow meters, a schematic diagram of which is given below. From the diagram it can be seen that the full output from the needle valves can be vented into the oven by error or by malpractice. The present accident occurred because of the combination of two circumstances. The operator had, on the previous day, ignited the A detector and, assuming that the needle valve A was similar to that in the F & M Model 810 series of gas chromatographs (that is, a simple on-off valve, restriction and control being carried out by secondary nonaccessible needle valves) had opened this valve approxi mately 3 to 4 turns. The hydrogen flame at this setting was approximately 6 to 9 inches long, and this was obviously incorrect. On Friday the ignition was repeated to investigate the reason for the flame length, but at the same time the column configuration had been changed and the A detector did not have a cap nut or column attached to prevent ingress of hydrogen from the detector into the oven. As stated, the explosion occurred within 10 seconds before any mal practice was obvious. Cause: Inadequate design -- unsafe procedure. Flow 1 Motor ionization detector From H2, ^ Ring U*in On/off vtlv* Column Effluent _^.0ven Line -34- 048748 Preventive Measures: Thai the Model 402 hydrogen flow system for each detector be modified to include a second needle valve, the setting of which should be fixed to provide a maximum flow rate of 60-80 ml. per minute hydrogen (i ,e sufficient only for the efficient combustion under normal gas chromatographic conditions). 2. The necessity for the use of cap nuts to seal unwanted detectors be suitably highlighted on the instrument. 3. The necessity for switching off the hydrogen flow at the main valve during column changing be also highlighted on the instrument. 4. Essential information for operation of the Model 402 be extracted from the F & M Instruction Manual and placed near the instrument. CASE HISTORY NO. 1718 Pyrophoric Reaction Description: Potassium tertiary butoxide was being stirred into dimethyl-sulfoxide in the laboratory when the chemist noted flames and smoke in the flask. He quickly stopped the addition, blanketed the contents with nitrogen and extin guished the fire. No one was injured nor was there any significant damage. Cause: The cause was attributed to small pieces of unreacted ^^ssium metal in the potassium tertiary butoxide. The ^Pplier was notified but future purchases will be carefully examined for free potassium. A similar accident in a labora tory in April involved sodium isopropylate. It was attrib uted to unreacted sodium metal in the solution. Preventive Measure: In view of this experience, it is prudent to check all materials that may contain unreacted pyrophoric materials. CASE HISTORY NO. 1719 Air-line Mask Connected to Nitrogen Hose Description A chemical operator suffered a partial asphyx iation and had to be hospitalized. For reasons which even the injured is unable to explain, he connected his air-line mask to a nitrogen hose. The hose to the mask was equipped with the female end of a conventional Snap-tite fitting. With some difficulty he was able to insert the nitrogen hose into this fitting. An air mask supply station with filter, reducing and pressure release valves were a short distance away. The injured had been working as a chemical operator only a few months. He was about to empty a tray drier which was not the injured's routine job but reportedly he had done it before. The injured had attended the chemical operator training classes which included instruction for the use of tfiiratory equipment. He does not recall his actions ^Biediately before his loss of consciousness. Cause: The nitrogen line was labeled but the label was not readily visible. Preventive Measures: (a) In view of this experience, all lines should be checked to make certain they are clearly labeled. (b) Consider possibility of reserving a special hose size and a special fitting for nitrogen use only. CASE HISTORY NO. 1720 Spontaneous Heating of Roofer's Mops Description: Following a small fire during roofing work, some tests have been conducted on the spontaneous heating of roofer's mops. Usual practice has been to place all such mops immediately in buckets of water, but in this particular instance the mop was not soaked in water but was left lying in the open as it was raining at the time and it was felt that the rain would keep the mop cool and prevent spontaneous ignition. However, in spite of the rainstorm, the mop did catch fire and also ignited roofing in the immediate area. This was a cotton mop. Tests were made of the ordinary cotton fiber mops and of mops made with a fiber glass material. In the tests, mops which had been put through operations resembling normal use of a roofing mop were removed from the hot asphalt and hung in the air to "cool." In this test there were four mops; two of cotton and two of fiber glass. Two were hung facing the slight breezes which were blowing and the other pair were hung with the mopheads away from the breeze. Temperature measurement started about 10 minutes after the mops were removed from the asphalt. The cotton mop facing the breeze was smoking within 10 minutes and burst into flame after about 15 minutes out of the asphalt. A temperature measurement of 300F was noted in one portion of this mop while flaming was taking place in another spot. The fiber glass mop was at 360F when temperature measurements were commenced. During the next 30 minutes the temperature of this mop gradually dropped to 200F. No smoking or tendency toward self-heating w'as observed with either fiber glass mop. Recommendation: On the basis of improved safety, it is recommended that fiber glass mops be substituted for the cotton mops in any roofing operations in the future. CASE HISTORY NO. 1721 Hydrogen Sulfide Description: A chemical operator was affected by hydrogen sulfide when, contrary to operating instructions, he removed a 1/2" plug from the head of a reactor to increase the discharge flow into a drum. He did not realize the vessel was under slight pressure. Fortunately, when he became aware that the H2S was escaping, he was able to replace the plug. A few minutes later he became nauseated and unconscious. Fellow workers carried him outside and se cured medical attention. Preventive Measure: This is an example of the need to avoid deviation from operating instructions. --35TM CMA 048749 CASE HISTORY NO. 1722 Ball Mill An aluminum zinc operator suffered severe bums on his neck and both arms when burning material erupted from a ball mill as he opened it. A fire had been discovered in the mill bv the operator on the preceding shift, who had inserted a nitrogen hose to blanket and extinguish the fire. Cause. Investigation determined that metering on the nitro gen system was inadequate to detect failure of the system to deliver nitrogen to the mill. Preventive Measures: Corrective steps include modification of the existing nitrogen lines, installation of additional ni trogen lines, and installation of additional rotometers to adequately monitor the system. The ball mill will be mod ified to eliminate exposure of the operator while opening the cover. CASE HISTORY NO. 1723 Sampling Line Description: Repairman suffered disabling chemical and thermal bums to his right eye when sprayed by a 12% caustic solution. He was working near a one inch iron pipe sampling line which extended 12 feet to the ground from a two inch Hetron nozzle. The employee bumped the one inch iron pipe sampling line which caused the nozzle to break, and he was sprayed with a 127c caustic solution. Preventive Measures: Corrective measures include pro vision of proper mountings and support for such piping, instruction of employees on the hazards of such lines (par ticularly when constructed of plastic type materials), and a review of use of plastic type materials in improper service conditions. CASE HISTORY NO. 1724 Steam Hose Description: Injured was struck by steam from a 3/4" hose while crossing a wooden walkway on the ground level of the plant. This hose had been hooked up to a mixing "T" and inserted into a 2" flexible hose for steaming. The hoses were not secured. A co-worker diverted water from the system into a tank. The resulting pressure differential caused the 3/4" hose to "back out" of the flexible hose just as the injured was going over the walkway. Cause: Hazardous condition created by previous shift leav ing unsecured hose in walkway. Preventive Measures: 1. All hose being used to steam out equipment, tank cars, drains, etc. should be firmly secured to compen sate for pressure differentials, surges, etc. 2. Steam hoses should not be left in walkways. 3. Inasmuch as this is a plantwide problem, each area should make a job safety analysis of their steaming procedures. The possibility of installing letdown sta tions and other devices should be considered. 4. Plantwide publicity will be given to this accident to remind all employees of the inherent hazards involved in working with hose. CASE HISTORY NO. 1725 Caustic Valve Description: The injured employee was on the first level of the main structure. He was washing off the deck under the brine surge tank with 10% caustic. The chemical goggles he was wearing had become fogged and he had raised them up on his forehead. As he reached up to turn off the caustic valve, the stream of caustic from the hose hit something and caustic sprayed back on his face. Caustic entered behind his spectacle type safety glasses and got into his right eye. Cause: 1. A process problem (tar in brine surge tank). 2. The use of 10% caustic for washdown. 3. Fogging of chemical goggles. 4. Failure to wear proper eye protection. Preventive Measures: 1. Study the possibility of adding oil or "bottoms" to brine surge tank to liquefy the tar. The tar could then be funneled to a dumpster and disposed of in the incinerator. This would not only eliminate the problem of tar disposal, but also the area would not be a housekeeping problem. 2. Discontinue washing down with caustic. 3. Use of anti-fog solution which is available for use on chemical goggle lens. 4. The frequency of eye injuries in this department points out the need for an educational and enforcement pro gram on proper eye protection. 5. Plantwide publicity will continue on the wearing of chemical goggles for hose handling. CASE HISTORY NO. 1726 Sampling Description: Injured had caught a sample of first cut receiver and was going up north stairs to second level to titrate sample. He was carrying chemical in eight ounce sample bottle without a top. About midway of first landing, he slipped or tripped, and in doing so, he threw his hand upward and threw the chemical on left side of face and into left eye. Injured was wearing safety glasses and safety hat Preventive Measures: ]. A written procedure must be posted in all units on how to take and handle chemical samples. 2. All personnel must receive special training in handling of chemical samples. -36- CMA 048750 CASE HISTORY NO. 1727 ^.manent Injury Clearing Blocked Valve Description: An operator suffered amputation of the distal phalanges of two fingers while attempting to dear a blocked rotary valve. The blender operator in Styrene Compounding tried to add the mixture to the weigh hopper in line No. I via the automatic weigh system. No polymer was being transferred however, and he correctly diagnosed the problem as "plugging at the rotary valve under silo #208." He proceeded down to the silo area and pinned out the rotary valve at the stop push-button (interrupter switch) which is located about 3' from the inspection port (see drawing). Since the locking pin was missing from this unit, he had to use a welding rod to hold the push button in the "in" position. The inspection port was then opened and the plug partially cleared by hand. The port was then closed and the rotary valve started by removing the welding rod from the stop button. It was apparent from looking in the lower inspection port that the polymer was not flowing and he went through the pin-out, manual clean out, and restarting procedure again. Still no polymer was flowing. At this point, he decided that he would starve-feed the rotary feeder by partially clos ing the gate valve at the bottom of the silo. This was done and he opened the inspection port and manually tried to unplug the polymer when the amputation occurred. He stated that he forgot to pin-out the rotary feeder. The following unsatisfactory conditions were found: , There are no written or established procedures for unblocking the rotary valves. 2. The Plant lock-out was not followed. 3. They could find no evidence of verbal instructions/procedures for unblocking rotary valves even though this operation has been done many times since startup by both maintenance and production men. 4. The plugging of these valves has been a continual problem right from startup and has required as many as five unplugging operations per shift. The plugging has been attributed to two causes: a) Inadequate venting of the rotary valve through the small screen at the rear of the valve adapter will not permit polymer to flow into the valve and hence polymer conveying stops. The normal way to correct this is to clean the screen. Work is underway to correct this problem and three of the four adapter pieces have been changed. b) Lumpy or frozen material required opening of the front inspection to unplug. This may have been the cause of the blockage which resulted in this accident. 5. Four of 6 shut-off pins were missing on the stop buttons for the blowers and rotary valves under the large silos. These have apparently been defective for a several month period and no one had paid any atten tion to them. Causes: 1, The primary cause of this accident was the failure of employee to lock-out the equipment prior to work ing on it. 2. Secondary causes: a) Unsafe design of a rotary valve which permits access to rotor while valve is operating. b) The inconvenient location of the stop button and missing stop pin could have been factors in the operator being unaware of the stop button not being pinned out. c) The remote location of the valve disconnect and lock facilities could discourage the use of the lock out procedure. The worker then tends to rely upotl the stop button. Preventive Measures: 1. Complete replacement of feed spouts and vents under all silos which will enable inspection ports to be sealed off. 2. Train all personnel who will work on this equipment on the correct lock-out procedure at the switchroom for all unplugging of the rotary valves. 3. If the modifications from recommendation #1 above are not satisfactory, then a positive disconnect at the motor of each rotary valve must be installed so that the inspection port cannot be opened before the motor disconnect is opened. 4. On future design where rotary valves are used, in spection ports where necessary, should be designed in such a way as to make it impossible for anyone to get his hand in contact with the rotor. CASE HISTORY NO. 1728 Electric Shock Description: A construction employee received a severe electric shock when he was handling a broken 460-volt portable power cable connector body. The cable had been parted to avoid damaging it while a portable platform scaffold was being moved. The front section of the case aluminum housing which contains an indexing keyway to insure proper polarity was broken off. This condition permitted improper mating and energizing the terminal equipment, plug and broken part of the connec tor body. -37- CMA 048751 The mason who received the shock had one hand on the part connected to the cable which was grounded and the other hand on the part which became energized when the plug was inserted by a second man. Under these condi tions, the mason received 277-volts from one hand through his body and to ground through the second hand. Because of muscular contraction, he was frozen to these parts and the circuit. His co-worker recognized what was happening and ran to the wall receptacle forty feet away and discon nected the cable. Precautionary Measurei: 1, If electrical equipment has any noticeable defects, do not use it until repaired. 2. When using extension cords or cables, thelast connec tion to be made should be to the circuit. CASE HISTORY NO. 1729 Sprinkler Activated by Gas Analyzer Alarm Description: In this incident a sprinkler system was tripped automatically by the gas analyzer alarm system. It was on outdoor equipment in typical metro-chemical operations. On investigation it was found that there was an aldehyde leak at flanges in a 3-inch process reflex line running at about 90 lbs. per square inch. This flange is approximately 4 feet from a pump driven by a steam turbine. It is felt that the immediate detection of the leak by the gas analyzers and the instantaneous opening of the sprinkler system in all probability prevented ignition. The gasket in the flange had been replaced in a recent plant overhaul but apparently flanges were insufficiently tightened. With the sprinklers in full operation, men wearing protective clothing tightened the flanges and the leak was stopped. CASE HISTORY NO. 1730 Laboratory Glass Description: The injured was carrying out a standard bulk density determination in the plant laboratory. This determi nation involves the placing of polymer chips in a glass measuring cylinder and tapping the mass down until a fixed volume is realized. The volume of the material is then weighed. The operation took place on the top of a stainless steel topped bench and the injured rested his left hand on the top of the cylinder and tapped the glass with a polythene bottle held in his right hand. The polythene bottle was the one from which he had extracted the polymer. His left hand steadied the cylinder during the operation. The glass of the cylinder broke and his left hand descended onto the broken edges and the palm sustained a deep laceration. Cause: Unsafe method. Preventive Measures: 1. For this operation in future, plastic measuring glasses should be used. 2. Instruction should be given to laboratory operators on the proper method of carrying out such a procedure or similar procedure. CASE HISTORY NO. 1731 Loaded Pallet and No Safety Shoes -- Foot Injury Description: A pallet had been loaded one-sidedly in a dark room operation and was being moved through a light lock on a hand pallet truck when the load tipped against the wall. A second pallet was brought into the light lock so the load could be transferred and restacked. During this opera tion another man came up and noticed that the elevating mechanism was raised. Without warning, he stepped on the foot pedal to lower the pallet. The operator who was transferring the load had just placed his foot beneath the pallet and when it dropped, his foot was injured. He was not wearing safety shoes. Safety shoes probably would have reduced the extent of the injury. Precautionary Measures: Loads should be centered on pal lets and on pallet trucks. Machinery should not be put into motion until all parties are clear. CASE HISTORY NO. 1732 Inadequate Gauge Description: A gauge was ordered to detect pluggage of the Brink Demister Pad in the air receiver tank, equipment number 1653. When the gauge, a Dwyer 2050 was deliv ered, it was given to the injured to make the installation on the north wall of the compressor building behind the air receiver tank. Several days later on November 19 when necessary connection lines were installed by pipefitters, the injured proceeded with the installation. The installation con sisted of a connection from the inlet side of the Brink (High Pressure) and a connection from the outlet of the Brink (Low Pressure). Each connecting line had a shut-off valve with an equalizing line and valve before the line shut-off valves. The injured connected the gauge on the wall about head high, He then proceeded to open the equalizing valve to prevent a surge across the gauge and simultaneously opened the inlet and outlet valves slightly. At this time, he was standing in front of the gauge's plastic lens face, although the shut-off valves were slightly to his left. When pressure entered the gauge, the front cover (plastic) exploded and pieces struck him about the face and a large piece (about 2/3 of the front) struck him in the nose. The frame of his safety glasses was broken from the fragment impact. The injured shut off the air valves and proceeded to the dispensary for treatment. The fact that he was wearing safety glasses may well have prevented serious eye injury. Observations and Findings: The pressure reading on the receiver on December 2 at 2:15 p.m. was 107 psig. -38- CMA 048752 The gauge ordered was specified for 50 inches of water ifferential pressure but no specific specifications were made as to the working pressure the gauge should withstand. The catalog describes the Dwyer 2050 gauge as suitable for a maximum working pressure of 25 psig. There was no information contained with the gauge or on the gauge show ing its working pressure. Cause. The gauge purchased and being installed was not of suitable pressure rating for the pressure intended. Communication between the person ordering the gauge and the person specifying the gauge was not complete. This caused the design error. Gauge was limited to 25 psig and working pressure was 90 to 100 psig. Preventive Measures: 1, Engineers specifying or ordering instruments and similar items must make certain that the item is suit able for the critical factors of temperature, pressure, etc. Special attention is required to be certain instruc tions are complete. 2, Maintenance supervision to discuss incident with all pipefitters and instrument men to make them aware of the possibility of this type of problem. If an apparent incompatibility of the installation with the system exists, people should be encouraged to ask questions concerning design specifications. 3, Review this incident with all plant personnel concern ing the value of wearing safety glasses to avoid unex pected ejections of liquids, solids, etc. CASE HISTORY NO. 1734 Hot 50# Caustic Sprays Onto Employee Description: A reactor operator, attempting to draw1 two gallons of caustic into a porcelain pail, found the causticflush line inlet plugged. The caustic line is insulated and has 150 psi steam tracing under 50-60 psi pressure. To unplug the line, he inserted a hot water hose nozzle into the open end of the flush line inlet with the inlet valve open. Another operator turned on the flush line while the reactor operator held the hot water hose nozzle. As the plug broke loose, hot 50# caustic sprayed back on the reactor operator and over a 30 foot area. The other operator, some 20 feet away, was also in the path of the spraying caustic. The reactor operator suffered second degree chemi cal burns to his mouth, soft pallet, and throat, plus minor burns to his face, ear, neck and both arms. The other operator sustained minor chemical bums. Cause: 1. Employee attempted to unplug line by an improper procedure. 2. Operator was not wearing required personal protective equipment prescribed in the operating directives for handling hot or corrosive chemicals, breaking lines or unplugging lines. The directives indicate that gog gles (chemical), face shield, rubber gloves, head pro tection, and long sleeves are required 3. Hot 50# caustic flush inlet line is subject to plugging due to sodium chloride crystals settling out. CASE HISTORY NO. 1733 Laboratory Explosion Description. A laboratory technician had prepared a silver ing solution containing silver nitrate, ammonium hydroxide, and ethyl alcohol, inserted the glass and left it to silver. Meanwhile, he attended to a first aid case for which he removed his safety glasses. Having occasion to go to the First Aid cabinet he paused on the way to stir the silvering solution As he did so, it exploded in his face. The employee sustained serious damage to both eyes. Preventive Measures: 1. Caustic will be piped directly to the vessels where it is to be used. 2. The incident has been discussed with all supervisors with emphasis on maintaining minimum safe operat ing procedures through inspection rather than expec tation. 3. Safe operating procedures, hazards of the job, and results of deviations will be reviewed with the injured employee. 4. Appropriate disciplinary action will be pursued with the injured employee for failure to observe safety rules and regulations. Counseling in proper safety attitude will also be provided. Cause Lack of knowledge. The silvering mixture being used always has potential for explosion. Unfortunately, the reference used for the process being followed failed to emphasize this fact and the injured was unaware of it. Prevents e Measures: 1. In the future, any laboratory work outside of standard procedures will be cleared through Quality Control Supervision. 2. Re-instruction is being given to all laboratory tech nicians in the wearing of safety equipment in laboratories. 3. The explosive potential of the chemicals used in this case, as well as others covered in NFPA 491 M, "Manual of Hazardous Chemical Reactions," will be reviewed with all laboratory technicians and others concerned. CASE HISTORY NO. 1735 Crane Jib Failure An extension jib on a crane boom failed suddenly w hile being used in replacing a concrete roof slab which w eighed just over 5 tons. The slab fell 100 feet from the building roof to the ground. The badly damaged jib and the jib strut also fell to the ground close to the crane cab. Fortunately, no one was under or near the load except the crane operator in the cab. While investigation has not pinpointed the cause of failure, it is possible that a cotter pin which holds in place one of the two support pins for the jib was missing This would allow the support pin to slip out of place, thus putting -TQ _ CMA 048753 the load on the remaining support pin. The operator may have started side swing too suddenly. There was a slight overload as the jib was rated at 10.000 pounds and the actual weight of the slab was 10.330 pounds; however, this, in itself, should not cause failure. The jib had been sandblasted, inspected and painted 3 months earlier, with no defects being noted at that time. The accident illustrates one of the hazards present with crane operations, especially those invoicing boom extensions'and jibs. The need for careful assembly and inspection is obcious. and keeping personnel out of any danger area in hoisting operations is also of great importance MOTE: Some companies require testing of boom-type equipment before use on plant premises. Hoisting equipment is tested for 125 percent of the anticipated plant lift, using the boom length and angle anticipated for the job. A dyna mometer is required for this test. CASE HISTORY NO. 1736 Chlorine Tank Car Preventive Mensures: 1. Move derails from west to east side of chlorine spur to prevent a derailed car from going into the chlorine dock. 2. Install lock on the derails with keys to be held by Building Supervision and the shift foremen only 3. Install full wheel stops on the south wheels of the north car. on the north wheels of the center car and the north wheels of the south car. The installations on the north and center cars to be permanent. 4. Use the center car for emergency purposes only. Keep unhooked until necessary to use. 5. Discontinue the use of wood for car stops across the plant. Install standard stops where needed and put into use. Chocks to be installed and removed by per sonnel hooking or unhooking car. 6. Reverse placards on empty cars to indicate to the railroad that they are empty. 7. Retrain the gatehouse attendants as necessary to insure their ability to provide first aid service in any emer gency. 8. Follow the recommendations of the committee on Chlorine Emergency Equipment and Procedures. 9. Re-emphasize to all personnel the need for proper protective equipment. "NO DEAD HEROES" Description The plant chlorine system consists of three tank cars on a special spur. Typically one car is used to supply users, the second is on stand-by hooked up and the third is an "empty" ready for switching or an unhooked full car. This was the situation at the time of the accident. Car 942 was on the north end empty, unhooked, and waiting to be switched out. The center car was feeding the system and the south car 1116 was on stand-by. full and hooked up. At 6:45 p.m. the switch crew approached the chlorine spur from the south end, connected to car 1116 and pro ceeded to pull it out. After moving about twenty feet the flexible connections hooking the car to the header and the main header line ruptured. Chlorine w'as released from the header system and the center car. The excess flow valves on the car operated immediately. The manual valves were then closed by the building personnel. The released chlorine drifted through nearby' buildings. Eight people were treated at the hospital for chlorine inhalation and released. No disab ling injuries resulted. Obserwitions: 1 The switch crew- stated they had the proper car number to be removed. They stated they had simply made a mistake and pulled out the wrong car. 2 The placards denoting empty/full cars were not reversed on either car 942 or 1116 indicating both w'ere full. 3, All cars were chocked with miscellaneous pieces of wood. 4 The gatehouse attendants were insufficiently trained in responding to emergency situations. 5. Both derails were in place. The south derail was turned by the railroad switch crew' before the car was moved. 6. One of the injured entered chlorine fumes without a Scott Air Pak or gas mask. Cause: Human error by railroad crew conductor. CASE HISTORY NO. 1737 Waste Material Dumper Accident Description: This accident occurred while maintenance was being done on a box dumper, a device which lifts two containers of scrap fiber approximately 10 feet above floor level and dumps them. The dumper unit is powered by an electric motor with a sprocket and chain drive system which operates a cable drum hoist. The unit had been reported as operating unevenly and it was assumed that waste fiber in the chain drive mechanism was the cause. While performing maintenance on the dumper, the mechanics raised the elevating platform to the raised dump ing position. A fenced enclosure gate on the unit was closed -- as it must be for the unit to operate. With the platform in the raised position, the mechanics then raised the gate and entered the operating area. Finding an accumulation of fiber in the drive mechanism, the mechanics began pulling entrapped fiber from the chain. At this point the drive chain slid off of the sprocket drive, releasing the cable drum and the dumping platform fell. Two workmen were injured, one was struck by the falling platform and the other was pinned beneath it. Cause: The direct cause of the accident was the slipping of the drive chain from the sprocket, causing the cable drum to revolve freely and allowing the dumper platform to fall. Contributory causes included failure to chain or block the platform in its raised position and the use of a brake on the motor rather than the cable drum. Preventive Measures: To prevent recurrences of this acci dent. the motor gear and drive chain have been completely enclosed to keep fiber from accumulating on the sprocket. A vane-type switch will be installed on the unit. The switch will not allow the dumper to operate unless the enclosure -40- CMA, 048754 gate is properly closed and latched. Should it be necessary work inside the gate with the dumper platform raised, afe Work Permit will be required before the gate sw'itch can be deactivated and the dumper platform must be posi tively secured. Employees are being reinstructed regarding the hazards of working beneath raised equipment. In addition, an in\estimation of several other mechanical mod ifications of the equipment is underway. This accident highlights the need tor providing positive protection in situations in which people are working under elevated mechanical devices A necessary added safeguard is close supervision b> thoroughly trained personnel. CASE HISTORY NO. 1738 Safety Shoe Saves Description: A man unloading coal at an unloading station has reason to be happy. He wears safety shoes. As he was kicking a wood block from in front of the wheel of a railroad hopper car, the car rolled onto the toe of his safety shoe. The steel toe-cap saved him from a crushed foot and perhaps complete loss of his toes. Instead he lost a couple of toenails and received bruises to his toes. This is a good example of the value of safety shoes. The accompanying photograph certainly depicts that an ordinary pair of shoes would not have provided the protection he received. stated he was going to steam out the caustic line to storage from the unloading pump. The foreman noticed the plugcock valve between the load ing and unloading pump was open. In the process of closing the valve the chemical hose blew' off the shank coupling connected to the valve and sprayed the foreman's thighs and legs with steam and caustic. Cause: 1. The tank truck was not suitably equipped for pressure unloading operations. Tank trucks equipped for pres sure were supplied previously and pressurizing to pro vide the suction head to the unloading pump is nor mally used if needed. 2. There were no operating instructions to cover this abnormal unloading procedure. 3. Operator failed to check the system prior to intro ducing steam which pressurized the system. 4. Foreman failed to instruct operator in safe operation. Preventive Measures: 1. Chemical transfer hose for 50% caustic will be eliminated. Solid'piping, Chiksan joints, and flexible metal hose will be used in transfer operations. 2. The superintendent and the general foreman will carry out a counseling and training session with the spare operator and the shift foreman to cover emergencyunloading procedures. 3. Establish agreement with the Purchasing Department for a minimum acceptable standard for tank trucks delivering 50% caustic. 4. Checking operability of eye baths will be mandatory as the first step in all loading and unloading proce dures. CASE HISTORY NO. 1739 Thermal and Chemical Burns Description: A foreman was directing the unloading of 50% caustic from a tank trailer. Normal truck unloading proce dures had been modified to overcome freezing problems attributed to low temperatures and blizzard conditions. A gear pump had been connected between the tank trailer the top unloading pump with chemical process hose ^^Fprovide additional suction head to the unloading pump. After unloading the truck, the spare operator shut off the gear pump, disconnected the hose from the truck and proceeded to shut off the unloading pump. Operator also CASE HISTORY NO. 1740 Tank Entry -- Two Fatalities Description: A tank semi-trailer had been flushed with water and since it had previously held flammable liquids, it was being purged with an inert gas to finish drying the inside prior to loading. The foreman observed that there was mois -41 ture on the walls of the tank and instructed the employee enter the tank wagon to wipe down the inside walls d posted another employee at the manhole as observer. The foreman then left the area. In a short while the employee in the tank collapsed. The observer then contacted the fore man who observed the condition at the tank and returned to the building to obtain self-contained breathing apparatus and additional help Arriving back at the tank, the foreman noted that the observer had also entered the tank apparently to attempt rescue and was subsequently overcome. Both employees were removed from the tank by rescuers wearing self-contained breathing apparatus, harnesses, and life-lines. Both men were declared dead on arrival at the hospital. Came: Proper operating procedures were not followed prior to entering the tank, that is, no safety work permit was obtained which requires that the atmosphere in the empty tank be checked for oxygen level and the presence of toxic gases, vapors, and substances. Self-contained breathing apparatus, body harness and life-line were not used. The flow of inert gas w'as not stopped. Preventive Measures: All employees have been re-in structed to follow standard operating procedures, The use of vessel entry procedures, including safety work permits, has been re-emphasized with all supervisory per sonnel. CASE HISTORY NO. 1741 oduction Explosion Description: Twenty-seven people were injured from blast and subsequent fire. Five were hospitalized with disabling injuries and one disabling injury became a fatality. Explosion and fire damage was concentrated in the north end of the building. There was little missile damage. The north wall toppled over from the pressure wave generated by explosion. Despite extensive damage, there was little damage to operating equipment in south section of structure, due most probably to fact that the blast occurred near the roof over the north bay of the building. Just prior to the explosion, operators saw a reddish-brown liquid overflowing from the lye platform on the third floor west side of Chums 2 and 3 and through floor grating onto ground level. Although origin of the material was not obvi ous to witnesses they did observe ignition of this stream. All churn systems and stills were operating at the time of the explosion. No abnormalities were observed other than falling liquid. Exterior walls of the building had substantial window areas from which panels are removed each summer. The explosion demonstrates that walled structures are capable of containing flammable vapors sufficient for destructive explosions even though there are substantial open areas in the walls for venting. About 330 gallons of reaction mass backed-up from No. 1 Churn into No. 1 Lye Dissolver, ^Approximately 470 gallons of ethyl alcohol and 800 Pounds of flaked caustic (NaOH) were added to the dissolver on top of the churn material. After a brief mixing period of highly exothermic and vigorous spoilage reaction occurred. Material erupted from the lye dissolver onto the lye floor then overflowed onto No. 1, 2 and 3 Chums, through tloor grating and to the ground floor. Alcohol vapors collected in the north end of the building and ignited causing the explosion. Subsequent fires were caused by ignition of erupted liquid. Cause: After studying available information, the Committee could not conclusively determine the sequence of events that led to No, 1 Chum material backflowing into No, 1 lye Dissolver and, therefore, chose not to speculate on the cause. Preventive Measures: 1. Provide an operating control center that will afford maximum personnel protection. 2. Open up the building structure to preclude accumu lation of flammable vapors. 3. Improve and simplify alcohol distribution system. 4. Provide inerting for vessels handling flammable materials. 5. Install explosion suppression systems on the churns. 6. The Committee strongly feels the need for general tightening up in the areas of operations, maintenance, training and immediate follow-up of problems. CASE HISTORY NO. 1742 Ultrasonic Welding Description: A research worker in another company was operating a 20,000 Hz per second Branson #320 Ultrasonic Welder to join two nylon parts w'hen he received severe burns and damage to the skin and tissues of his left hand. The ultrasonic welder had been equipped with two-hand controls for safety reasons. However, the controls were deactivated and a foot actuated control was substituted. The researcher w'as in a laboratory working on the machine when he accidentally stepped on the foot control. This activated the equipment; the 80-lb head came down onto his hand and held it there until the cycle was complete -- 4 seconds. This caused extensive bums to the tissue and four fingers of his hand. Preventive Measures: 1. Deactivation of safety devices creates hazards. If one means of safety must be circumvented, a second means should protect the worker. 2. The manufacturer's instructions should be studied before using equipment. Make such instructions a part of the job safety analysis. CASE HISTORY NO. 1743 Caustic Solution Burns Foot Description: A Fusion Operator suffered bums on his right foot and ankle when he brushed against a small overflow drum which was being washed out with hot water. The hot water caustic solution ran down his leg and into his boot. -42- CMA 048756 ause: Investigation revealed a deviation from existing pracces for the cleaning of the drums, failure of the man to ave his boot properly laced, and inadequate instruction of personnel concerning actions to be taken in event of such exposures. Prcu'iunt Manures. Corrective actions include improved maintenance to reduce need for use of such drums, required use of proper area for drum washing, training of operators, and increased surveillance of the operation by the shift foremen. CASE HISTORY NO. 1744 Getting the Point! Description A mechanic tripped as he was descending a flight of stairs. As he fell a man who was coming up the steps caught him. However, the man coming up the steps had a wooden pencil in his shirt pocket with the point up. The mechanic's eyelid struck the pencil point and he suffered a laceration from it. Though the injury was not too serious, a little reflection about the circumstances causes us to shudder at what could have happened. This is the third similar incident in a few months in which sharp pointed pencils were being carried point up in pockets. 'Causes. 1. Unsafe position of pencil in shirt pocket. 2. Failure of mechanic to use handrail. Preventive Mensures: 1. Wooden pencils are fine tools for work at desks: they should not be carried in pockets because they are a hazard to ourselves and others, The mechanical pencils are best for pocket use, with the point down. Pocket Protectors are available from stock to protect yourself and your pocket from the pointed end. 2 Pencils should not be carried in pockets point up. 3. Protect yourself from a fall by placing your hand on the handrail when descending stairs, CASE HISTORY NO. 1745 Serious Falling Hazard Description: In this accident it was extremely fortunate that the injured man escaped with relatively minor injuries --- a dislocated and lacerated right middle finger. The accident could easily have produced very serious injury. It is occasionally necessary to remove a motor and stirrer from a reactor by means of an overhead crane. A special jig has been built to handle the motor and stirrer in its movement from the operating location to the maintenance fthop. This jig is a fairly large structure and is lowered through a hole at the second elevation of this wall-less build ing until the bottom end of the jib rests at the first elevation. The second and third elevations are covered with metal floor grating. The jig extends through the second floor ele vation and is secured against the side of the third elevation platform in a vertical position. While the injured operator was at the second elevation observing the cable on the overhead crane, he inadvertently stepped into the hole in the grating falling a distance of 11 feet 7 inches. The operator was aware of the opening in the grating but became preoccupied in watching the crane cables and block to warn of double blocking. Preventive Measures. Since the accident, supports have been provided at the edge of the second elevation which permit placing this jig in a relatively narrow slot outside of the main building structure which has eliminated the necessity for the high lift and also eliminated the necessity for the floor opening. This incident indicates the necessity of reviewing all job operations, especially maintenance operations, and pro viding proper facilities for doing the work safely. CASE HISTORY NO. 1746 Dust Fires in Blenders Description: A series of fires erupted on the blender floor where four men were working. All of the men received burns with three of the injuries classified as serious and one as disabling. An inspection of the blender floor after the fires revealed dust explosions and fires had taken place in three of the thirteen blenders and in the dust collection system serving the blenders. Operator A was charging #10 blender and had completed the magnesium stearate and water addition, and was in the process of charging titanium dioxide. He was encountering severe dusting in the charge chute and was intermittently operating the blender to minimize this problem. While reach ing for another bag of additive, a flame erupted from the charge chute of # 10 blender narrowly missing him. Operator A then looked down towards #9 blender and proceeded in that direction after noting no obstructions. When he reached #9 blender, a flame erupted from that charge chute and burned him on the face and arm. Operator D, who had been sweeping between #9 and #10 blenders, also noticed the flame from #10 first. He was also burned on the face and arms by the eruption from #9 blender which followed. On the other end of the blender floor, Operator C had just checked #6 blender and had gone to check #1 blender. He lifted off the cover from the charge chute on #1 and as he was placing the cover down, a flame shot out, burning him on the face. Operators A, C and D all had injuries which were classified as serious. Just prior to the fires, Operator B was lying on the blender walkway attempting to disengage the charge chute from #9 blender which was now down for seal repacking and alignment. As he was adjusting his body position, a flame burst out from around the charge chute burning him on the face. He immediately stood up and ran down the stairs when a second major flame emerged from the #9 blender (probably from the already open dump door) burning Operator B on the arms, back and back of the neck. The burns to Operator B covered 27% of his body with some areas potentially being 3rd degree bums. This injury was classified as disabling. it - CMA. 048757 There were several common events involving all of the operators. All were wearing paper suits which afforded no protection since they simply disintegrated when exposed to the intense heat of the flames. This was most pronounced with Operator B whose arms were burned except where his undershirt and gloves protected him despite his paper suit which extended to his wrists. All of the operators went under the safety showers before leasing the area. None of the operators recall turning in the fire alarm. Cause: The almost simultaneous explosions in several blenders and the evidence of a tire and/or explosion in the connecting dust collection system which released burn ing material into the blenders clearly show this system as the vehicle for an ignition source to each of the blenders. Blenders #1,5 and 9 were all empty or partially so and each had contained material which would lead to a dusting condition within the blender. This combination of dust and high oxygen level led to the dust explosions in these blend ers. The initial source of ignition is believed to have come from #9 blender. This hypothesis is based on the evidence of frictional heat from the dump pan rubbing and the possible presence of tramp metal. The lack of any evidence of an ignition source in any of the other blenders or the dust collection system itself supports this. Number 9 blender had stopped rotating some 7-8 minutes prior to the fires which indicates polymer must have begun to bum prior to stopping the blender. It is assumed the heat generated from friction in #9 Mender resulted in a small fire, probably around the front "of the blender, and some burning material was drawn into the dust collection system. The heavy dust loading in this system in the area of #10 blender probably ignited first, propagated fastest and accounts for the flash being seen at this blender before any of the others. The rolled polymer in #9 blender remains a mystery. The most likely theory for its formation is that the intense heat generated in the blender caused the polymer coating on the wall to curl and fall oft. The primary cause of the accident is believed to have been a detective dump chute in #9 blender which generated sufficient friction heat to ignite resin. A small flash fire resulted and ejected burning material into the dust collector system. A dust explosion in that system then followed result ing in the discharge of burning polymer into each of the blenders through the blender vent. Dust explosions resulted in certain blenders where the proper combinations of mate rials, dusting, and oxygen were present. (Defective equip ment.) Preventive Measures: 1, Redesign the dust collection system to prevent the propagation of a fire or dust explosion. Specific approaches to be evaluated must include: a) Consultation with Fenwall. or other manufac turers, on the installation of an explosion suppres sion system. b) Determine the feasibility and economics of instal ling a nitrogen purge at the extremes of the dust collection system to reduce the oxygen level to below 109?. c) Re-orient the blender vent nozzle. d) Determine the effectiveness of a choke or seal in the ductwork between the blender intakes. e) Determine the need for explosion relief panels in the dust collector unit. f) Re-evaluate the static grounding provisions in the dust collector system. 2. Maintenance personnel should be retrained in the in stallation of the stop bar and a fool-proof installation scheme should be investigated. 3. A check-list should be instituted for the blenders so that they can be thoroughly inspected after color changes in a uniform way for mechanical deficiencies. Also, this incident and the various recommendations should be reviewed with all blender floor personnel, 4. The use of the paper work suits should be eliminated in favor of an outfit which will afford greater pro tection from heat sources. 5. A formal safety design review involving the Plant Safety Engineer should be held on every plant project where safety devices or systems are potentially required. Additionally, the Plant Fire Chief should be notified when any new projects are installed in the plant. CASE HISTORY NO. 1747 Equipment Rupture Caused by Dicyanobutene Polymerization Description: In the refining of unsaturated dinitriles, it is necessary to prevent overheating, or polymerization will occur and accelerate rapidly with the evolution of gas and the formation of a coke-like residue. After many years of successful operation, an incident occurred in a dicyano butene refining operation, beginning as an apparent loss of vacuum in an evaporator and ending with the violent rupture of process equipment. Cause: It is believed that a restricted line from the vacuum evaporator resulted in excessive hold-up time at elevated temperature, this initiating an exothermic reaction. The polymerization propagated from the evaporator to distillation columns through a common vacuum header, and the pressure in the columns quickly rose above atmospheric pressure. Relief valves opened at 30 psig but were unable to cope with the gas and vapor generated by the dicyanobutene reac tion throughout the distillation train. Eventually the pressure exceeded the strength of a condenser mounted on top of one of the distillation columns, and the condenser ruptured with considerable violence. The tower internals were ejected through the opening caused by the condenser failure, and it is believed that the fatality experienced during the incident was the result of a missile. There was no evidence of an internal explosion and there was no ensuing fire involving process materials. Preventive Measures: 1. The separate vacuum jets which had been provided for each component of the refining train will be used, and the use of a common vacuum header will be eliminated. 2. Additional instrumentation will be provided to permit a more accurate assessment of process status in the individual components of the refining train 3. The feasibility of increasing the relief valve capacity and lowering the pressure settings is being explored. -44- CMA 048758 CASE HISTORY NO. 1748 ng Hair A young lady with lo\ely long hair recently had an acci dent that fortunately was not serious. But it easily could have been extremely so. She was operating an offset dupli cating machine when her hair became entangled in the ink roller system. Fortunately, she reacted quickly and hit the stop button almost instantly. Result -- a head-full of ink stained hair and a sadder but wiser operator. There is much kidding, arguing and parental nagging these days regarding the pros and cons of longer hair styles for men and women. But when it comes to long hair and moving machinery, there is no question -- they are an extremely dangerous combination! Please remember -- if you favor the longer hair styles and are working near ma chinery with moving parts, see to it that your hair is re strained in some positive manner while on the job. This is equally important for both men and women. Caps, nets, snoods, sweat-bands, pins, clips, etc., can all be effec tive -- but be sure to use some form of containment. CASE HISTORY NO. 1749 Overflowing Caustic Burns Face and Eyes Description: An operator suffered chemical bums of the right eye, and multiple bums on the face, neck, legs and oulders w hen he was splashed with a 207c caustic solution, e had just finished mixing the batch of solution and opened the transfer line valve. The air purge to the transfer line had not been shut off, and air pressure entering the batch mix tank caused an overflow of the solution. The employee used an eye wash fountain, but failed to use the safety shower before coming to the Medical Department, and the seventy of the injuries was increased by this lack of prompt flushing. returns outward allowing the dockboard to return to the raised position. However, the dockboards will also descend when a load is placed on them, rising again when the load is removed. As the man moved onto the loading dock, he was moving the machine in reverse. He claims the reverse control stuck and he attempted to swing the machine sideways to clear the dockboard. He was unsuccessful; the dockboard descended and he and the scrubber fell off the edge. The man received severe facial lacerations, bruises and contusions. Preventive Measures. 1. Do not enter dockboards with equipment unless the dockboards are supported by a truckbody. 2. Facilities are now available on the third floor to store and service this equipment. Orders have been issued to service this equipment at no other location. CASE HISTORY NO. 1751 Temperature Controller -- NaK An accident has been reported involving a Honeywell T-654-A temperature controller which has a NaK (sodium potassium alloy) fill thermowell. At or near room temperature, NaK is a silvery white liquid. It will ignite spontaneously in air. Reaction with water generates hydrogen with sufficient heat to ignite the hydrogen in air. It is not unusual to cut the capillary when removing the unit for scrap. An instrument mechanic was burned on his arm when he cut the capillary of the NaK-filled thermowell system. Honeywell in their "Maintenance and Repair" bulletin for this T-654 unit warns as follows: "WARNING -- Rupture of these elements can cause physical harm to personnel Defective elements should be returned with your parts order to Honeywell for disposal," Preventive Measures' Corrective steps include installation of a gauge to indicate air pressure in the lines, modification of the recycle pump discharge line to keep it above the liquor level in the mix tank, installation of a check valve in the transfer line, and instruction of all operators involved in operation of the system. CASE HISTORY NO. 1750 A Fall From A Loading Dock Description: A man had been operating a battery-powered Clarke floor scrubber during the "C" trick on the second floor When he finished cleaning the second floor he decided to change the water. He took the machine to a first floor drain into which he emptied the dirty water. To fill the machine, he went to a loading dock where he knew there was a hose ^ There are four Kelley counterweighted dockboards at this ading dock. They are designed so that when a truck or trailer backs into the dockboard, it pushes a plunger back toward the dock, thus, lowering the dockboard to the truck bed. When the truck or trailer is moved away the plunger CASE HISTORY NO. 1752 Bagging Machine Description: An operator caught his hand in a bagging machine sustaining partial amputation of three fingers. The bagging crew of the 8-4 shift was starting up the #2 Bagpak after maintenance had been performed on the dogging plate of the machine turret. The tape on this machine had fed through the taping unit and caught on the knife and on front drive sprocket. The Senior Operator reached with his left hand to grab the tape and disentangled it while the machine was still running. His hand was caught between the carrier chain and drive sprocket. Cause: a) Failure to follow lock-out procedure. b) Operation procedures not followed: Senior operator involved in this accident was involved in a similar accident three months ago although instructions have since been stressed in safe bagging machine operation. c) Short cutting: Did not want to take time to shutdown the machine. --45 - CMA 048759 Preventive Measures: The Committee observed that two additional guards on this machine were missing. Practice of operating machinery without all guards in proper position should he reinforced. CASE HISTORY NO. 1753 Hydrogen Sulfide Fatalities Description Sis tannery workers died from exposure to hydrogen sulfide when a tank truck of sodium hydrosulfide was unloaded into an open tank containing chromic acid solution. After discussion with the foreman in charge, the drivers made the hookup and started pumping. About 180 gallons had been discharged when the first man collapsed and others, thinking he had had a heart attack, ran to his assistance and were themselves fatally exposed to the hydrogen sulfide fumes. The truck driver stopped the pump and closed the valves when he saw them collapse. Firemen using self-contained breathing apparatus rescued others who might have also become exposed. Cause: The pipe connections for both the sodium hydrosulfide and the chromic acid solution were only one foot apart. They were nor identified and the foreman was expecting deliveries of both the chemicals. Preventive Measures: 1. Clearly identify pipe connections. 2. Include analysis in identification. 3. Require tank truck driver to have a bill of lading. 4. Require foreman to sign that he has ordered the ma terial unloaded into a specific tank. 5. Include product identification in the safety training program for all employees. CASE HISTORY NO. 1754 Unloading Dimethylaniline Description: A warehouseman and a truck driver, an employee of a common carrier, started to unload a tank truck of Dimethylaniline. According to the warehouseman, the truck driver checked the control on the air actuated outlet valve to be sure it was closed. The warehouseman then removed the pipe cap. Dimethylaniline gushed out under full head pressure of the tanker. The warehouseman and the truck driver were sprayed with Dimethylaniline when the warehouseman made repeated attempts, and was finally successful, to replace the cap -- thus keeping the loss of product to a minimum. According to the warehouseman, the truck driver was unable to close the air actuated outlet valve. Both the truck driver and warehouseman were washed off under a safety shower. The warehouseman was wearing approved chemical goggles, rubber apron, and rubber gloves which undoubtedly saved him from more serious injury. (However, the warehouseman removed his goggles before entering the safety shower and the flow' of w'ater from the shower washed Dimethylaniline into his eyes. Both the warehouseman and the truck driver were examined at the hospital and the truck driver was released that afternoon. The warehouseman, however, suffered chemical burns of both eyes requiring hospitalization. Approximately 1230 lbs. of Dimethylaniline were lost from the tank- truck. Quick action by the warehouseman prevented loss of the entire 40,000 lbs. The spilled Dimethylaniline ran into a drainage ditch and from there into a ravine and thence into a creek. Most of the water in this ravine comes from the overflow of the cooling pond, which comes from the city water supply. As soon as it was noticed that the Dimethylaniline was running into the ravine, the Maintenance Department was notified. They quickly stopped the flow of Dimethylaniline by digging earthen dams. Quick action by the Maintenance Department prevented more than a comparatively small amount of Dimethylaniline, estimated at less than 20 gallons, from entering the creek. Dimethylaniline is insoluble and lighter than water. A slick about 100 to 200 feet long developed which did not proceed beyond approximately 200 feet from the mouth of the outfall (about 1.8 miles above the mouth of the creek). Low rate of flow in the creek as well as a strong upstream wind kept the spread of the slick to a minimum. Within thirty minutes a flexible boom was delivered to the problem area and with the aid of maintenance people and a boat, the slick of Dimethylaniline was soon encompas sed by the boom and trapped permanently so that it could be removed by spreading straw over the surface. Inspectors from various government agencies, who came in to inspect the area after hearing of the incident com plimented the company for so effectively cleaning up the creek. Cause: 1. Air operated bottom valve was open, but according to truck driver, it appeared closed. 2. According to the common carrier truck driver, `'Com pany employees loaded the tanker with unloading line still capped and without checking the valve." Preventive Measures: 1. Tank trucks of this type should be filled with the pipe and hose caps removed to be sure outlet valves are not leaking. 2. A manual valve should be installed between the air operated valve and the pipe cap, 3. The controller for the air operated valve should be enclosed under lock and key. CASE HISTORY NO. 1755 Maintenance Mechanic Struck in Face by Autoclave Sight Glass Description: Two mechanic trainees were assigned the job of cleaning the sight glass on an autoclave. They had loosened the holding ring of the sight glass and attempted to loosen the sight glass itself with a screw driver. They were unsuccessful so they removed the holding ring and one of them tapped the sight glass with a hammer. On impact of the hammer the sight glass (approximately 6 inches in diameter and weighing 5Fi pounds) broke loose and was propelled upward, striking one of the trainees in the face. -46- CMA. 048760 The force of the impact drove him backward and he fell ^^he floor. The injured trainee was startled but did not consciousness. " Employees in the area telephoned the dispensary, assisted the injured onto a stretcher, and moved him to the ground floor after checking him to be sure there were no broken bones. The fire alarm was activated at the dispensary and a nurse and the rescue squad responded. The injured was taken to the hospital for examination which disclosed a fractured nose, facial lacerations and contusion, and contu sion to his right hip. The injured employee returned to work after treatment. Came: The Injury Review Board findings for this serious injury were: 1. The equipment had been out of service for approx imately two months and pre-startup activity was in progress, 2. The pressure buildup in the autoclave was due to an open instrument gauge connection (inert gas). This purge stream was not secured when the equipment was shut down. The autoclave vent was closed. 3. Neither mechanic expected the autoclave to be under pressure. Both men had worked on equipment in the system over the past two months and had not en countered any pressure. 4. .Neither mechanic had checked with operating person nel prior to starting the sight glass job. 5. No procedure card had been issued for the sight glass job. The procedure being followed by the operating supervision in this particular unit was to wait for notifi cation by maintenance personnel before preparing a procedure card and securing equipment. 6. Safe work procedures for situations where equipment had been down for an extended period of time were not clearly understood by either operations or mainte nance personnel. The primary causes of this incident were the lack of communication between the maintenance and operating per sonnel, and the assumption by maintenance personnel that since the autoclave had been out of service for an extended period it was safe for performance of the sight glass job. Preventive Measures: The Injury Review Board offered the following recommendations: 1. Procedures requiring maintenance personnel to obtain Operating Department permission prior to working on any and all equipment should be enforced. 2. The importance of constantly maintaining safety awareness should be re-emphasized to all maintenance personnel. 3. The Maintenance Department should review work procedures for opening sight glass flanges. Evaluate existing procedures and establish safe procedures as required. 4. Re-emphasize to all employees the importance of using the plant fire alarm system to summon help to the site of an emergency. CASE HISTORY NO. 1756 ^^frayed with Hot Water and Steam Description: Operator was attempting to clean a slippery floor area with steam and water. When valve was opened by another operator, the 150 pound steam pressure caused a check valve to close in the water line. The two inch hose discharged hot water and live steam so violently that it slipped from the operator's grasp. He was sprayed with hot water and steam before he could escape the danger area, and sustained first and second degree burns to portions of his body, face, neck, arms and legs. Cause: 1. Using 150 pound steam and water to clean floor area. Operator did not think the open-ended hose would permit back pressure to close off the water. (Operator failed to follow supervisor's instruction for cleaning the area. He decided steam would be quicker.) 2. Having a hose station for 150 pound steam. This hose is equipped with steam fittings for washing after coolers . Preventive Measures: 1. Hand-held hoses will never be used with more than 30 lb. steam and then only with supervisory approval. 2. Hose stations for 150 lb. steam will be eliminated. 3. A job procedure for use of 150 lb. steam and water in aftercooler washing will be developed. CASE HISTORY NO. 1757 Hose Failure Description: The injured employee was filling an anhydrous ammonia nurse tank (1000 gallons) from a storage tank when the load-out line hose from the storage tank ruptured at the attachment to the riser. The employee was wearing protective clothing but the pressure from the line rupture was so great that it tore a hole in his raincoat and ammonia sprayed under his left arm and down his left side. The employee immediately entered a safety shower nearby and washed himself. Cause: The load-out line from the anhydrous ammonia stor age tank ruptured causing ammonia to spray on the employee. Preventive Measures: 1. A new load-out line hose has been installed. 2. All ammonia storage tank hose lines will be inspected once a month to determine their physical condition. Any hose lines showing signs of cracks or damage will be replaced, CASE HISTORY NO. 1758 The Case of the Errant Cylinder The anchoring of compressed gas cylinders, to keep them from being knocked over with the accompanying possibility of breaking off the valve, is an accepted safe practice in most companies. However, there has occasionally been some skepticism expressed as to really what would happen if a cylinder valve were knocked off. We now have firsthand knowledge as to what happened in one case thanks to a compressed gas cylinder (CO2) -47- CMA 048761 that caused several moments of frenzied activity in a building under construction. Six 220-cubic-foot cylinders, part of a fire extinguishment system, had been moved away from their wall supports to allow painters to complete painting the area. While mov ing them back into position, it was noticed that one cylinder was leaking A painter had the cylinder leaning against his shoulder, and was attempting to scoot it across the floor. At this moment the valve separated from the cylinder and was projected backward hitting the side of the steel cabinet. The man suddenly found himself with a jet-propelled 215-pound piece of steel. He wrestled it to the floor, but was unable to hold it. The cylinder scooted across the floor hitting another cylinder, knocking it over and bending its valve. The cylinder then turned 90 to the right and traveled 20 feet where it struck a painter's scaffold causing a painter to fall 7 feet to the floor. After spinning around several times, it traveled back to its approximate starting point, where it struck the wall. At this point, the cylinder turned 90 to the left and took off lengthwise of the room, chasing an electrician in front of it. It crashed into the end wall 40 feet away breaking loose four concrete blocks. It turned again 90 to the right and scooted through a door opening, still chasing the elec trician. The electrician ducked into the next door opening, but the cylinder continued its travel in a straight line for another 60 feet, where it fell from a dock into a truck well. The balance of the cylinder pressure was released as the cylinder spun harmlessly around in the truck well area. The painter who fell from the scaffold received multi ple fractures of his leg. It is surmised that the cylinder valve had been damaged previously, and it was a matter of chance that it separated from the cylinder at this particular time. This incident vividly illustrates what can happen when a valve is accidently separated from a compressed gas cylinder. This one contained pressure of about 900 pounds per square inch, but many cylinders are pressurized to 2,200 pounds per square inch. If you are at all skeptical about the need for anchoring compressed gas cylinders, you might think about those 2.200 pounds per square inch and ask yourself: "What if * * * *?" CASE HISTORY NO. 1759 Care and Storage of Acrylic Acid and Acrylate Esters Description: A gallon glass jug of ethyl acrylate exploded in the Routine Analysis Laboratory of an Analytical Section. Fortunately no one was directly in the line of the explosion and therefore no one was injured. Cause: The cause of the explosion was the heat and pressure resulting from polymerization of the ethyl acrylate within the capped jug. The ethyl acrylate had been obtained from a 55-gallon drum stored outside the laboratory. The gallon jug had been in the laboratory for several months and was apparently used for preparing blends of different components in ethyl acrylate. No obvious cause of the polymerization could be found, although a power failure at the laboratory the night before resulted in higher than normal laboratory temperatures. The clear glass gallon jug in question was exposed to some sunlight. The 55-gallon drum outside the laboratory' was subsequently analyzed for inhibitor content (MEHQ) and found to contain 20 ppm. It was indicated that in early purification studies, it was also noticed that ethyl acrylate obtained from the 55-gallon drums exhibited a tendency to polymerize at room tempera ture (as evidenced by the boiling of the material) All of the material taken from the drum was subsequently reinhibited with 2g of MEHQ and 2g of HQ per gallon of ethyl acrylate. It was recognized that this is probably an excess of inhibitor over that which is really required for safety purposes. Plastic bottles are also used as an extra safeguard. Numerous studies have been performed on acrylic acid, methyl acrylate and ethyl acrylate (varying the concentration of MEHQ and the temperature) at another laboratory. All of the studies involved the storage of material in metal drums, cans, brown glass bottles or polyethylene jugs. None of the data obtained are applicable to the storage of ethyl acrylate in clear glass jugs. Preventive Measures: In order to minimize the possibility of future explosions due to polymerization of stored material, it is recommended that the following conditions be strictly observed: 1. All acrylic acid and acrylate esters should be inhibited to a minimum of 200 ppm MEHQ if they are to be stored in the laboratory for longer than one week. 2. All acrylic acid and acrylate esters to be stored in laboratory should be placed in brown glass and/or polyethylene bottles or jugs and kept away from any heat source. 3. All acrylic acid and acrylate esters ordered in the future should be inhibited to a minimum of 200 ppm MEHQ prior to shipping. The 55-gallon drum presently on the laboratory storage rack will be inhibited to a minimum of 200 ppm MEHQ. CASE HISTORY NO. 1760 Benzole -- Sampling An explosion and subsequent fire occurred in a byproducts complex which included a tank farm containing fourteen 10,000 gallon horizontal tanks and a naphthalene house; the construction details refer to the naphthalene house. A discharge of static electricity occurred when a sample of unwashed benzole was taken from one of the 10,000 gallon storage tanks through a manhole using a leadweighted glass bottle. The spark ignited the benzole vapour and resulted in a severe explosion and fire. The whole complex was protected by a water and/or foam pouring system fed from a continuously-manned fire station only 100 yards away which contained two 650 gal/min elec trically-driven static pumps, a tank containing 600 gallons of foam compound and another containing 12.000 gallons of water. The system was actuated but it proved of very limited value because the initial explosion and subsequent heat damaged the supply pipework and open pourers. The tank in which the explosion occurred, the naphthalene house. 4,000 gallons of naphthalene oil, 5,000 gallons of other flammable liquids and 10 tons of crystallized naphtha -48- CMA. 048762 I r ags were severely damaged by explosion, fire and heat. | of the other storage tanks in the farm were damaged ire and heat. A 17-year-old male suffered bums to the hands and face. The reconstruction of the plant has been considered an uneconomic proposition and the refining of crude benzole will in future be carried out by outside contractors. Quarterly Safety Summary of the British Chemical Industry Safctv Council CASE HISTORY NO. 1761 Leak Test Description: The injured employee and a co-worker were pressure testing a reactor kettle in which ethyleneimine had previously been used. Ammonia gas mixed with nitrogen gas was being used to pressure test the system. A lighted sulphur taper was used to test for leaks. During the leak test procedure, a leak was discovered at a union joint in the reactor kettle roof vent line. As this joint was opened, a small amount of liquid came out and was ignited by the i sulphur taper. The tire was quickly extinguished but both II men were exposed to chemical vapors. (Presumably vapors of ethyleneimine.) sulphuric acid. Subsequent test explosions have shown that the factory explosion was due to the high concentration of the reaction mixture. Since 1966 more than 350 batches of dimtroaniline chloride have been diazotized in the reaction vessel where the accident occurred. With a view to making the process safer and easier to handle, however, production of nitrosylsulphunc acid on the premises was discontinued in 1967 after a minor discharge occurred in a kettle where the reaction had already ended. Supplies from outside were used instead and it was thought that this new starting material would make it possible to work with more concentrated charges and, thus, result in a better use of available kettle capacity. After a series of laboratory tests, operations were earned out in the plant. Before the third operation was completed the contents of the kettle exploded. The explosion was found to be the result of a local increase in temperature which set off a chain reaction affecting the entire contents of the kettle and leading to their exploding. While it was known that a sudden temperature change might well cause a certain amount of decomposition in the laboratory, conditions required for an explosion had not been obtained prior to the accident in the plant. Quarterly Safety Summary of the British Chemical Industry Safety Council Cause. The reactor system had not been completely cleaned out prior to testing the system for leaks. ^H'he employee and his co-worker were not wearing ^P^Hratory protection when the vent line was opened. Preventive Measures: All employees will wear respiratory protective equipment (supplied air type) whenever opening lines on the reactor. Operating procedures will be written to include the drain ing and blowing of kettle vent lines to insure complete cleanout of the reactor kettle system. CASE HISTORY NO. 1762 Venting Description: An instrument mechanic was burned on both hands, face and leg by nitric acid. He shut off the nitrogen supply to a faulty differential pressure cell and disconnected the nitrogen line. Four pounds of residual pressure in the reactor to which it was connected, forced nitric acid up the bubbler tube spraying him. Preventive Measure. In addition to reinstructing the mechanics on proper venting of vessels, a shut off valve will be installed on the vessel nozzle. CASE HISTORY NO. 1763 troaniline Chloride The explosion in the azo'dyes plant on 23rd December, 1969, in which three people died, occurred during the diazotization of dinitroaniline chloride with nitrosyl- EDITOR'S NOTE A reader comments as follows: "1 have received a translation of a Swiss article on the thermal stability of diazo bulk mixtures and diazo com pounds. The article is very explicit with regard to this case history and reports that the ingredients charged to the reactor which exploded included 384 grams of 40% mtrosyl sulfuric acid and 287 kilograms of 6-chloro-2,4-dinitrotoluene. Obviously this is a vastly different compound from dinitroaniline chloride." CASE HISTORY NO. 1764 Drum Not Clean Description: A shipping tankerman was filling acetaldehyde into general service 55 gallon returnable stainless steel drums which had been previously cleaned and "pickled" with acetic acid by a contract drum cleaning company. The drums were being purged with nitrogen and internally inspected with a drum light prior to filling. The tankerman noticed a strong odor of acetic acid when he inspected the empty drum but did not consider this to be abnormal because of the "pickling" operation. Immediately following the filling of a drum and the installation of the bung, the tankerman observed that the drum was becoming warm. The drum was immediately taken outside the building with a fork lift truck and set on an open truck dock where the foreman loosened the 2" bung in the vapor space on top of the drum. Fire water was sprayed on the drum to cool it. The drum continued to vent through the loosened bung for several hours. Cause1 It is assumed that the drum had not been properly rinsed after the "pickling" operation and there was sufficient -49- CMA 048763 acetic acid remaining in the drum to initiate a polymerization reaction, Preventive Measures' 1, The contract drum cleaner was contacted about im proved cleaning procedures. 2. Tankermen have been instructed to not fill any drum which has a foreign odor. 2, A committee will be convened to study and make recommendations on how to handle a "hot" drum. CASE HISTORY NO. 1765 Oxygen Used Wrongly As Purge Gas A manufacturing plant had been shut down for general repairs. When these had been completed, it was necessary to purge the gas lines with nitrogen to exclude the presence of air. The nitrogen was supplied from cylinders attached to various purge points located in the system. During the purging process, it was discovered that a cylin der of oxygen had been connected into the system in place of a cylinder of nitrogen. This was immediately replaced with a cylinder of nitrogen and purging continued until tests showed that it was safe to start the plant. A few days prior to the incident, an operator from the plant had taken requisition from his supervisor to the stores to collect two cylinders of nitrogen. At that time, alterations to the stores were being carried out and the normal storage area for cylinders was not in use. Instead, the cylinders, which included oxygen, nitrogen, acetylene and propane had been transferred to a temporary storage area on the other side of the works road, immediately opposite the stores. Having presented his requisition to the stores assistant, the operator was told to help himself to the two cylinders and the temporary storage area was pointed out to him. Although all the cylinders were clearly marked with the appropriate colours, evidence suggests that he took two cyl inders of oxygen instead of nitrogen. He admitted later, that he had no knowledge of the cylinder identification code and did not know the difference between an oxygen cylinder and a nitrogen cylinder. Having returned to the plant with the two cylinders, he obtained the assistance of two other operators to deposit the cylinders by the purge points at which they were to be used. Neither of the two operators remarked on the fact that the cylinders were different in any way from the nitrogen cylinders in normal use. Later the supervisor, himself, connected one of the cylin ders to a purge point and failed to observe the difference in appearance. On the day before the incident, the same supervisor with a member of the technical staff inspected the purge points and again, the error went unnoticed. During purging of the hydrogen lines, it was discovered that an oxygen cylinder had been used in error. The oxygen cylinder, which was empty, was immediately removed and replaced with one containing nitrogen and the system had to be re-purged. The second oxygen cylinder had not been connected to the other purge point, and this was also removed from the plant. Although at least four people had handled the cylinders, it seems evident that familiarity with the job had conditioned them to "see" only that which they expected to see. The obvious difference in cylinder markings had been completely unnoticed by them. It was also clear that not all operators were aware of the system for identifying cylinders and that the control of issues from the stores was not sufficiently rigid, although at this particular time the use of temporary storage areas made control a little more difficult. It was recommended that: (1) The control of issues from the stores be more strictly enforced. (2) All plant staff be made aware of the system for identifying cylinders. This will be reinforced by dis playing illustrated charts of the British Standard identification colours in the cylinder stores and ir all plants where cylinders of any type are used. In addition, all purge points where gas cylinders are used will be marked with the name of the gas and with a graphic illustration of the cylinder and relevani colour coding. Quarterly Safety Summary of the British Chemical Industry Safety Council EDITORIAL From a New York City correspondent: "The case history ... is based upon British Safety Stan dards that apparently identify cylinder gas content by a colo: code with the chemical name as an additional (optional? method of identification. "In the USA, the name of the gas is the method o identification. In the case of medical gases only, with thei restricted number of gases, color can be used but only a: a secondary (additional) method of identification. We firmly believe that color coding of gas cylinders can be an unsaft procedure due to the large number of gases and gas mixture' that need identification, the variations in paint colors it different lights, fading etc., etc. "It is felt that the major reasons for the error in usinj oxygen as a purge gas were the failure to read the ga; cylinder label or possibly the use of compressed gas fron unmarked cylinders ..." From the State of Israel, Ministry of Health - Haifa: "In Case History No. 1765 we were astonished tha nobody recommended use of different threads and nipple; for the different gases. I know that such agreed standarc connections exist in the United States, and in England even if maybe they are not enforced by law, not to mentior the pin-index for medical gases. "The story of four different persons `seeing only tha which they had expected to see' would not have been writter if it had been necessary for one of them to get a requisitior to a lathe operator to make an adaptor to enable them ti connect the wrong bottle to the right inlet." Editor's Comment: Color coding of compressed gas cylinders is not ar accepted practice in the USA. Two ANSI standards arc applicable. Section 3.1 of Z48.1-1954 states that "compressed gas cylinders shall be legibly marked with at least the chemical name or a commonly accepted name -SO - CMA. 048764 uf the material contained." Secondly, ANSI Z57.1-1965 Rrompressed gas cylinder valve outlet and inlet connec tions" specifies the connections required for the various gases, including medical gas connections. This standard is designed to pres ent the interchange of regulator equipment between gases which are not compatible. Cylinders in interstate transportation require a DOT label which identities the category of gases. Precautionary labeling is also generally adopted. The HAIFA correspondence awakens a controversy of interest to all chemical safety engineers. One thing is agreed upon -- that a customer should not accept a compressed gas cylinder not properly identified. The following commentary was received from the Com pressed Gas Association. "The primary source for information regarding the con tent of any compressed gas cylinder should be by means of the printed word. In other words, there should be a mark ing or label on every compressed gas cylinder indicating the gas or gas mixture that is contained in that cylinder. Sections 173.400 through 173.403 of the Code of Federal Regulations, Title 49 deal specifically with these require ments. These regulations have been amplified by a recent directive issued by the Department of Transportation under HM-28 which makes this type of marking mandatory effec tive December 31, 1971. "These regulations mean essentially that all compressed gas cylinders must comply with the DOT labeling require ments which consist primarily of a four inch diamond on he side of the cylinder which contains the name of the ttas and other appropriate information. As an alternative option to this, flammable and nonflammable compressed gas cylinders may carry a red or green diamond on the shoulder which must be at least one and one quarter inches on each side indicating that the gas is either flammable or nonflammable. On the left hand side of the diamond, in black letters on a white background, must be the name of the gas as it appears in the hazardous materials list of the DOT Regulations, "As a secondary means of identification, we feel that the configurations of the valve outlets in each cylinder should conform with the United States and Canadian Standards that are applicable to the various gases. Copies of CGA Pamphlets V-l and V-5 give existing information on this subject. These salve outlet configurations are pretty gener ally followed in this country and Canada and the medical requirements are followed in a number of countries overseas. "The use of colors in identification of gases generally has a lot of appeal when it is talked about in the general sense by a user, because most users do not have occasion to consume very many gases at any one operating location. There are in excess of one hundred gases being commercially transported in this country today and the number will prob ably increase rather than decrease in the future. From a color point of view, there are seven primary colors plus balck and white in existence, so that gives us nine choices from a solid color aspect. It becomes obvious then with nine basic colors to choose and over one hundred commodi ties to identify that the only way of using colors would be to go into a program of striping or segmental painting of cylinders using different colors and quite possibly differ ent shades of the same color. If this was done, then the color code in fact becomes another form of communication or language. It would serve no useful purpose if the people handling these cylinders were not familiar with the color and this seems to be the case m the particular accident your paper reported. In view ot this fact it makes sense to require marking or labeling spelling out what is contained in the cylinder. "There are a sizable number of employees working in both industrial and medical establishments today that are either partially or completely color blind. If we were to depend on color coding it would be essential that steps be taken to be sure that all employees handling these products were tested to be sure that they could identify the colors. Very few1 companies or organizations, to the best of our knowledge include in their employment examination tests to determine w hether or not employees can detect differences in color. "Industrial establishments today have many variations of atmospheric composition which can have an effect on the color of the paint of a piece of equipment, particularly if we w'ere to go to various shades of the same color. These industrial atmospheres may well change the color and make the identification by this means difficult. In a similar manner, many different types of industrial lighting are in use today and often a given color appears vastly different under varying types of lighting equipment. "Cylinders used in industrial applications are often sub ject to considerable abuse, and the paint on their surfaces is largely obliterated by wear thereby making identification by color difficult for this reason as well. This is one of the reasons why we favor the more recent DOT option provided for marking on the shoulder of the cylinder that is usually not subject to abrasion. "We certainly sympathize with the predicament ot all people who are engaged in protecting their own personnel and facilities as well as the general public. We do believe, however, that the three methods of identification, first the W'ord. then the valve and thirdly a color is the proper priority listing for cylinder content identification." CASE HISTORY NO. 1766 Restricted Use of "Explosion-Proof" Hand Lamps Recommended Description: The globe of an "explosion-proof" reel lamp exploded and fragments of glass were projected in grenade fashion. The unit shorted out and threw sparks when picked up by the handle after the explosion. The lighted lamp had been removed from a reactor and hung by its hook in clean air for about 15 minutes when the explosion occurred. The reactor from which it was removed contained a low concentration of Vinyl ChlorideVinylidene Chloride vapors (below the flammable range). The hand lamp had been serviced at the Electric Shop ten days prior to the incident. The globe of a unit of this same type exploded under similar conditions about 12 months previously. Conclusions: It is felt that the explosion was caused by pressure build-up inside the globe due to the heat generated by the lamp in the presence of water which had leaked into the globe. -51- CMA 048765 Recommendations: 1. Restrict the use of this type of hand lamp to areas where it will not be exposed to water or water spray and where the atmosphere is known to be safe. A hot work permit should be required. 2 Send the lamps to the Electric Shop for all mainte nance. including change of bulb. 3. Visually inspect the lamp before each use. If it has water inside the globe or if it appears to be defective in any way, it should not be used. Pertinent Facts' 1. This hand lamp was used to provide light inside the reactors so the operator could see to wash buildup from the reactor walls. 2. According to supervisory personnel, experience has shown that the concentration of monomer vapors inside the reactors is always below the flammable range after transfer of the product under the current transfer procedure. 3. Supervisory personnel have indicated that the cord on this reel lamp is not long enough to reach a vessel where the lamp could have been exposed to vapors in or above the flammable range. 4. It is not uncommon to find water inside the globes of these units. 5. There is a great deal of evidence to indicate that the bulbs in these lamps are being changed by route elec tricians. Since they don't carry the tools designed for this job, it is highly improbable that they can properly tighten the globe. The manufacturer recom mends that the globe be torqued to 30 ft. lbs. 6. The manufacturer has indicated that temperatures as high as 425F. have been recorded at the base of the socket when the lighted lamp is suspended in an inverted position (suspended by the cord) for long periods. It is assumed that this data is based upon the use of a 100 watt bulb (as specified). 7. The lamp becomes an ignition source when the globe is broken. Additional Comments and Questions: 1. The reactors are washed with 2000 psi water. During the washing process, the hand lamp is inadvertently struck by the water stream on occasions. What is the effect of this impact on the light? Could this explain the presence of water inside the globe? What are the thermal shock implications? 2. Could the specified 100 watt bulb have been replaced by a 150 watt bulb? If so, what maximum temperature could be reached inside the unit? 3. What possibility is there that the globe could be dam aged (scratched, chipped, etc.) when being returned to the plant from the Electric Shop or by rough usage in the plant? This could significantly weaken the globe. CASE HISTORY NO. 1767 Tank Explosion Description: A tar surge tank exploded resulting in one personal injury and extensive damage to adjoining distilling facilities and to the south section of the building. The injured employee received head lacerations and was absent from work a total of 22 days. The tar tank which exploded was part of an evaporator system being used for separating solvents from the mixture of waste solvent-sludge accumulated in a manufacturing operation. This evaporator system had been used in handling similar mixtures over the past two years without incident. The precise cause of the explosion is somewhat in ques tion, but an extensive investigation has led to the determina tion of a plausible mechanism for the explosion. It was general practice to add caustic to the starting material for the purpose of reducing corrosion during the process. Sub sequent laboratory evaluations have indicated that the addi tion of caustic to the specific tars involved initiated an exo thermic reaction which raised temperatures significantly above the normal process temperature. This reaction filled the equipment with a moist foamy charred residue and pro duced considerable quantities of non-condensed solvent va pors and nitrogen. This liberation of non-condensed vapors resulted in the imposition of a significant back pressure on the system. The reaction then proceeded with increased exothermic activity (perhaps accelerated by an attempt to add compressed air to unplug the lines) to the point of violent decomposition and ignition. As a result, large quan tities of hot gases were produced suddenly causing rupture of the tar tank. Subsequent chemical analy sis of the starting material has indicated the presence of significant quantities of nitrogen-containing compounds as residues from the pre ceding manufacturing operation. 1 ! Preventive Measures: The recovery system involved in this accident has not been reactivated and alternate methods are now in use pending development of a new recovery process. Several general conclusions can be drawn from this incident, some of which are tabulated below: 1. Well-established emergency procedures involving fire, medical, industrial safety, maintenance, depart mental and public relations functions operated smoothly and efficiently in this case. 2. Immediate activation of an investigative task force to collect proper data, samples, photographs and anec dotal information is vital to the ultimate success of a detailed investigation called for in a case of this type. The subsequent employment of a wide variety of technical skills, working as a team, is an efficient mechanism for determining the factors contributing to an accident of this degree of complexity. 3. Operators working with solvent processes should be thoroughly instructed and regularly reminded not to apply compressed air to these systems. 4. This accident highlights the potential dangers present in chemical recovery systems which process variablecomponent inputs. The need for economical operation plus the growing pressure of ecological considerations are demanding the increased use of recovery and recycling systems throughout industry. These systems require monitoring and reactivity evaluation to assure safe process compatibility of the various mixtures being handled. -52- CMA 048766 CASE HISTORY NO. 1768 Fire in a Laboratory Oven Description: A fire occurred in a laboratory oven during solubility testing of a mixture of ammonium perchlorate in diethyleneglycoldinitrate (DEGN). The damage was confined to the oven and its contents. The water jacket of the oven was strained at the seams and the walls of the jacket were distorted. The internal glass door of the oven was shattered and the front door of the oven distorted. The paintwork of the oven was smoke stained and blistered. All propellant samples and other samples under test were consumed in the fire. One 150ml. flask and the associated stopper was broken. Five samples of DEGN containing varying amounts of ammonium perchlorate were placed in individual 150 ml. conical flasks each fitted with a glass stopper. These flasks w'ere placed in the oven at 2:00 p.m. on the first day of the test and twice each working day the flasks were checked for color of the DEGN and the contents swirled to effect solution. The last check was at 4:00 p.m. on the third day. At some time in the early hours of the seventh day a fire occurred which caused the damage previously described. Besides the samples of ammonium perchlorate/DEGN the oven also contained test pieces of composite propellant based on polybutadiene rubber binder containing ammonium perchlorate and aluminum powder, some test pieces of epoxy-novlace resin and some silica gel. The total ex plosive content of the oven was 1.5 lb. of composite 3pellant and 0.8 lb. of ammonium perchlorate/DEGN. ^ The electrical controls of the oven incorporated a manual reset fail safe temperature control which had operated indi cating that the electricity supplied to the oven had been interrupted when the oven temperature had exceeded 60C. Investigation of the incident showed that there was some confusion between the parties discussing the use of the oven for the test. The fact that the duration of the test was seven days was not appreciated by the member of the laboratory staff agreeing to the use of the oven, In addition, the labora tory in which the oven was situated was cleared for modifi cations to the lighting system by electricians on second day and portion of third day. The samples of composite pro pellant were removed from the oven and the laboratory. The ammonium perchlorate/DEGN samples remained in the oven during this time. The samples of composite pro pellant were replaced in the oven on the third day following completion of the work by the electricians when the labora tory was returned to service. should have been recognized, particularly in a mixture of organic explosive and oxidant. 4. The duration of the experiment at elevated temperature increased the risk and particular attention should ha\e been given w'hen it extended over a holiday weekend. The location chosen for this work was unsuitable and a more isolated position should have been selected. 5. The fire was caused by the ignition of a mixture of ammonium perchlorate and DEGN maintained at 60C. for a period of approximately seven days. The fire might have been avoided and the consequences would have been reduced by greater attention to plan ning of the experiment. 6. In the planning of investigational work involving ex plosives or hazardous materials, greater care should be taken in the selection of equipment, the location of the experimental work in relation to other laboratory activities and to the need for strict observance of any instruction and procedures applicable to the work situation. Armed Services Explosives Safety Board Case History CASE HISTORY NO. 1769 Egg Grenade A girl who felt the need of a snack during a break period had a harrowing experience. She had two hard boiled eggs, already peeled, that she put in a microwave oven for a quick warm-up. They hadn't been in the oven very long and were not hot to the touch when she bit into one. An explosion ripped the egg apart sending yolk all over the place, but mostly over her face and eyelids; she was also burned on the lips, tongue and cheek. It was no hand grenade -- just an egg. But the microwave oven heated the interior and the hard boiled egg white was just strong enough to hold it together. Safety people were able to duplicate the egg explosion. Microwave ovens have their merits, but also their prob lems. Nothing, particularly a can -- nor as it seems, even an egg -- that has a non-porous casing should be warmed in such an oven. CASE HISTORY NO. 1770 Cleaning Device Taken Out of Service Preventive Measures: The Operational Safety Committee observations, conclusion and recommendation that, 1. The ammonium perchlorate/DEGN samples should have been removed from the laboratory for the dura tion of the clearance for work by the electricians. 2. The use of ground glass stoppers for vessels containing explosives is not good practice since the ground glass surfaces present a rough gritty surface to any explosive nipped between the flask and the stopper. Frequent handling increased the risk of accidental ignition from this cause. 3. The samples of ammonium perchlorate/DEGN were experimental and the possibility of a fire or explosion Description: A chemical operator suffered 1st degree bums about the head and back when hot water sprayed out of a special rod cleaner. The cleaner was a relatively new device which had been fabricated to clean stainless rods used in a fermentation process. In the operation, water was to be added before carefully opening the steam. In this instance, the operator did not add water. When he opened the steam valve, a little water in the bottom of the rod cleaner gushed out the top together with steam and struck the injured. Preventive Measure: The rod cleaner has been declared unsafe and taken out of service. -53- CMA. 048767 CASE HISTORY NO. 1771 CASE HISTORY NO. 1774 Batch Eruption Caustic -- Eye Injury Description A chemical operator received a chemical eye bum when a hatch erupted out of an open manhole. He made an error h\ allowing the batch to become too hot while he was doing other work. He erred again by not checking with his supervisor and started the agitator. This caused the batch to erupt out of the manhole which was left open for a subsequent water addition. Eye protection saved him from possible more serious injury but some of the material entered his eye while washing himself off. Preventise Measures: This accident emphasizes the desira bility of making water additions through nozzle connections or vessels rather than open manholes. CASE HISTORY NO. 1772 Working on Moving Equipment and Using Incomplete Tools Description. A grinder operator was removing bagged chemicals from a slat conveyor when his co-worker left the area to get a long handled broom. During the co-worker's absence the operator picked up a stiff bristled brush broom (without a handle) and held it crosswise on the slats using the 1/8" steel chute as a bearing point. (This slat conveyor .is approximately two feet wide and ten feet long with extra Idats bolted on top of the regular slats approximately every four feet.) One of the protruding extra slats caught the operator's right thumb between the 1/8" steel chute. Injury1 --- severed tip of right thumb between first joint and fingernail. Description: An operator added sodium hydroxide pellets to water while wearing the prescribed protective equipment and worked on something else while waiting for the exo thermic heat of solution to dissipate. When he later added this solution to a mixing vat. he failed to put his goggles back on. As the solution hit the agitator, some splashed into his right eye. He used the eyewash fountain immediately but it was believed that he did not open his eye while doing so. He suffered a chemical irritation to his eye but apparently no permanent damage. Preventive Measures: At least two significant conclusions can be drawn from the above incident. These are as follows: 1. In process areas where corrosive chemicals or other contaminants are present, proper personal protective devices should be worn at all times. In situations as above, it is virtually impossible to anticipate the exact moment when a splash or spill may occur, 2. Operators should be carefully instructed that if, in spite of the use of protective equipment, chemical splashes do occur in or near the eyes, very thorough flushing with water for a minimum of 15 minutes is required. After the initial washing period, during which the superficial contaminants are washed away, every effort should he made to keep the eye open as much of the time as possible. This requires the use of the hands to hold back the eyelids and expose the eye to the wash water. It has been our experience that the average individual is not able to hold his eyelids open by himself under these conditions. There fore, if it is at all possible, the help of a co-worker should be enlisted to hold the eyelids open. Causes: 1. Working on moving equipment. 2. Using defective and improper tool. Preventive Measures: 1. Enforce rule of not working on moving equipment. 2. Review work habits of all employees. 3. Repair or discard broken handled brooms. CASE HISTORY NO. 1773 Steam Supply Valve Description A chemist closed the steam supply valve to a sterilizer so the unit would cool overnight. When he opened it next morning, a deluge of hot water came out and burned his feet. Cause. It was found that the condensate line from the sterilizer was piped directly into a common condensate return line A steam trap from a building radiator was malfunct ioning permitting live steam to enter and pressurize the Bndensate return line. This prevented free condensate drain age from the sterilizer and probably permitted steam and hot condensate to back up into the sterilizer. The man suf fered second degree bums of both feet and ankles. CASE HISTORY NO. 1775 Double Fatality Purging Tank Car Description: Inadvertent use of nitrogen instead of air to purge a tank car, and failure to use protective equipment as required by Standard Operating Procedures, resulted in the death of two long service employees. The Muriatic Acid Car had been spotted on the Rubber Shop Tract for periodic inspection, washed with water, and entered briefly on June 1. The men then put a hose into the car to air purge it overnight, but mistakenly hooked the hose to a nitrogen header. The first man to enter the ear the next morning collapsed at the bottom of the ladder. His foreman entered the car to rescue him, and also collapsed. Lack of rescue harness or wristlets delayed removal from the car. Emergency treat ment, started immediately on removal from the car and continuing until arrival at the hospital, was unsuccessful. Laboratory tests revealed an atmosphere of nitrogen in the car which resulted in death by simple asphyxia. Preventive Measures: Corrective action that immediately got underway included a meeting of the Hazards Committee in order to review the causes of this most serious accident and submit recommendations in order to prevent recurrence. -54- CMA 048768 .sj] plant Supervisors will warn everyone that the Standard rating Procedures tor Tank Entry will not be deviated i unless first approved by the Department Superintendent and the Safety Department, All non-essential taps on nitrolTen lines will be removed and those that are considered jA'.ential will he clearly identified. Reinlei ' C onunent "Nitrogen ha' its advantages for purging, especially when flushing out the residual flammable vapors which may be in a vessel because it allows the vapors to be purged out without going through a very dangerous explosive range where high pressures may be generated, "We have been involved in the use of nitrogen for these purposes for many years and unfortunately have also been involved in asphyxiation or near-asphyxiations by its use. Some plants have, as a result, concluded that the dangers of serious explosions when preparing vessels for opening are lesser hazards than the possibility of axphyxiations due to nitrogen. Our plant does not share this viewpoint since it can be insured that all possible safety measures are taken to protect the workmen entering the vessels. "It appeared that the plant which reported the incident was possibly going to continue to use line air as a means of purging the nitrogen out of the vessels. It would seem to us that this has two major disadvantages. 1 There is always a chance of future mix-up of lines in spite of the best precautions to prevent this. 2. There have been eases reported of employees being overcome by plant air which contained traces of car bon monoxide. This carbon monoxide was introduced into the air by air compressors which may have had excessive quantities of oil in the air and possibly reach ing higher temperatures than normal. "For this reason, most of our industry favors the use of power blowers run by electricity to either add air to the vessel to be purged, or preferably with a duct to pull the air out. In the ease of a tank car, this duct is run as near to the bottom of the car as possible so as to change the atmosphere within the car as much as possible. The discharge of the blower must be away from the manhole area so as to prevent recycling. In our case, we have duct work connected to a fixed blower which evacuates to the roof. "For tanks which have atmospheres which cannot be properly purged, we favor the use of bottled air and also have such bottled air for emergencies. Large cylinders of this bottled air connected by a long line air mask is favored over the "back pack" type, as the man with a mask and no back pack is more maneuverable in a small manhole. "The use of plant air, in our opinion, is only a last resort measure. Instances have been reported where fast thinking employees have thrown an air line into a vessel, turned on the air, and revived those overcome. This, in our book however, is only an emergency measure." CASE HISTORY NO. 1776 enol Description: A laboratory assistant w'as carrying two half gallon glass containers of phenol up a flight of stairs when he slipped and broke one of the bottles. The phenol splashed on his face, neck and chest. He went down to a first floor locker room and attempted to wash the chemical off in a sink. Fortunately, another man realized the potential dan ger of phenol contact, got him under a shower and called for assistance. He did not suffer any serious poisoning from skin absorption and his eve injury is not expected to result in any permanent damage. Preventive Measures' This injury illustrates the need for proteeting glass bottles of hazardous chemicals by inserting them in closed metal or plastic carrying containers. CASE HISTORY NO. 1777 Overhead Door Description: An operator opened a metal overhead door and then left to bring a cylinder into the building. As he pushed the cylinder truck through he didn't notice that the door had slid down and he walked into the door. He momen tarily lost consciousness and on recovery found the cylinder and cart resting on his legs and chest. His head injury1 required 4 sutures but he did not suffer any1 other injury and did not lose time. Cause: Some doors do have a tendency to slip down, and on this one a safety latch was provided to hook the operating chain. The latch had not been used. Preventive Measure: Signs will be made to remind personnel to use the safety catch. CASE HISTORY NO. 1778 Solvent Error A laboratory chemist used some solvent from a can marked "hexane" to rinse a syringe that had contained a dilute aluminum alkyl solution. A rapid reaction occurred and the syringe plunger was propelled to the top of the hood. Fortunately, the chemist held the syringe away trom his body and he was not hurt. It was determined that the solvent can labelled "hexane" had erroneously been filled with methanol. CASE HISTORY NO. 1779 Laboratory Fire A laboratory immersion heater, controlled by a variac, was hung over the edge of a plastic bucket containing an aqueous solution and left overnight. By 6:00 a.m. the aque ous solution had evaporated and the heater melted and ignited the bucket. This in turn, caused ignition of a nearby stack of plastic buckets. A sprinkler head was activated and con trolled the fire. -55- CMA 048769 CASE HISTORY NO. 1780 Centrifuge Description An explosion occurred in a bottom-drop centri fuge followed by a fire. Fortunately, the major force of the explosion vented out of the large bottom opening. The hexane-ethanol solvent caused a minor fire that was control led by 2 sprinkler heads. The centrifuge cover distorted slightly, hut there was no other damage and no injuries. Cause. The machine was dismantled and it was found that five of the eight retaining bolts of the top retaining plate had been sheared. A strip of "blued" metal, indicating a definite hot spot and a significant amount of metal transfer between the two faces of the top seal, were found. This was the likely source of ignition. The machine had been given its annual inspection about six months previously. CASE HISTORY NO. 1781 Empty COa Extinguishers Description: A maintenance crew had to place a gear on the shaft of a drier drum. To accomplish this, the gear was heated with torches (to expand it) while the shaft was cooled (to cause contraction) with CO2 -- from a CCri fire extinguisher taken from the wall. The method works well but the practice of using fire extinguishers for this purpose takes them out of service when they might be needed. Supposing a fire were started with the torches! The extinguisher may be nearly empty when needed most. Misuse of fire extinguishers in this way has resulted in replacing a partially or completely emptied extinguisher to its original location. When it is needed to fight a fire it is useless. Preventive Measures 1. L'xe fire extinguishing equipment for the purpose for which it is intended. 2. When work requires materials used in fire extin guishers, the material should be procured from stock or a source other than fire fighting equipment. CASE HISTORY NO. 1782 Electrical Description: A shift electrician was called to make repairs to the DAP screen This screen uses an electrical DC vi brator to drive the screen. The DC was supplied by a rectifier system operating from a 440v supply. There was also in the immediate area another identical system to drive a screen for the MAP system. The area had been and was in the process of being cleaned up. Water and steam was used to do the cleaning. The area in front of the MAP rectifier box was wet and slick. The electrician had completed trouble shooting the DAP system and found that repairs would be extensive. He then returned to the control room to discuss the job with the Foreman and the operator. It was decided to use the rectifier supply from the MAP system. This had been done in the past by connecting the DC supply in one cabinet to the output connections in the second cabinet. In other words, to run the DAP vibrator from the MAP rectifier. The electrician left the control room to see how this tempo rary hook-up could be made. The control room was only a short distance from the two rectifier boxes and could be seen from the control room. He had opened the MAP rectifier box with a screw' driver to determine the hook-up technique, when the accident took place. The last he remem bered was having the screw driver in his right hand and on top of the cabinet and the other on the handrail which ran along the bottom front comer of the cabinet. The Foreman and operator (still in the control room) heard a shout and looking out of the control room noted that the electrician was in an irregular position in front of the cabinet and that something was wrong. The Foreman realizing that the electrician was frozen to something "hot" ran for the disconnect 10-15 feet past the electrician. He pulled the disconnect and the electrician slumped to the floor. He remained conscious and could talk but felt "sleepy." Immediate investigation was undertaken. It was noted that the main disconnect was engaged on the DAP system and the main disconnect was disengaged on the MAP system. An electrical engineer and electrician completely checked the MAP rectifier cabinet wiring for shorts and grounds. They found none. They found the electrical equip ment was functioning electrically correct. A screw driver was found wedged between a contact on a terminal strip and the upper left hand corner of the inside of the cabinet. The upper part of the screw driver showed evidence of burned flesh. There were no other signs of the occurrence. That is, there was no evidence of arcing, grounding, short ing, or condensate in the cabinet. All the internal parts of the cabinet were covered with a heavy layer of powder. The powder (Product) appeared dry and not gummy or sticky. The floor plate in front of the cabinet was wet and slick. The electrician completed the temporary hook-up. The system was energized and the cabinet checked for abnormal voltages, everything checked out OK. The system was started up and ran normally with intermittent checks made on its operation. The investigation was completed in three additional meet ings. At this time, all parties, including the injured were interviewed. He had no recollection of ever getting his hand into the cabinet. He was conscious that he was in trouble and attempted to yell to the people in the control room. He at least mentally made an effort to push himself away from the cabinet but could not physically. He noted mentally that "I hope they don't grab me." He later noted that he had a current passing through to his feet due to his wet shoes. There was no evidence of burns, etc. associated with such circumstances. Cause: The exact cause of the accident could not be deter mined. There were no direct witnesses to the accident and the injured himself does not know how he got into the cabinet to touch the electrical source. There are a number of specific possibilities. 1. The injured slipped on the floor and threw himself into the cabinet and onto the "hot" circuit. -56- CMA 048770 The injured's hand slipped off the cabinet and into the cabinet. The injured accidentally touched a "hot" terminal or wire inadvertently as he looked or was working in the cabinet. Based on the evidence collected and the personal interview with the injured, the committee feels that the accident resulted from cause No. I or 2. In addition, even though the accident would not have happened if the electrical dis connect had been opened, it was a normal procedure and proper technique to open the cabinet with the power still on. There was no evidence showing that any work had started toward making the connections which would have required the disconnect to be disengaged. The floor, adjacent equipment, and possibly the cabinet had been steamed down during the cleaning making the area slippery. The internals of the cabinets were completely covered with product obscuring most of the equipment in the cabinet. Preventive Measures: 1. Relocate the MAP and DAP rectifier cabinets to a dry area and make the cabinets dust tight. 2. Emphasize the procedure that NO ELECTRICAL EQUIPMENT be washed or steamed off. 3. Relocate the DAP disconnect switch to the same level as the rectifier cabinet. 4. Unplug the sewer that drains the area around the rectifier cabinets and next to the Power Panel on the tile floor level. Noted during the investigation were a number of elec trical hazards in the MAP/DAP area. Although they did not contribute directly to this injury, the committee feels that a complete audit should be made of these hazards and a schedule established to resolve them. 6. The lockout procedure should be reviewed with all plant personnel. CASE HISTORY NO. 1783 Fork Lift Truck Accident Description: The operator of an Automatic FFEH-40 standup docker was about to load an empty and cabless box trailer from a truck dock. The "pony" wheels were down and the rear tandem wheels were in the full forward position. The dock area was inclined slightly toward the street. As the docker carried the first load into the trailer, the trailer moved away from the siding about eight (8) feet. The docker, only partially into the trailer, fell rear end first between the trailer and the siding, and came to rest in a vertical position. The operator either jumped or was thrown clear and landed on his back on the Kelly Dockboard. As the docker fell, the operator was caught between the dockboard and the docker mast. Only the fact that the Kelly Dockboard dropped a few inches when the trailer moved away, thus providing sufficient room for the operator between the r mast and the dockboard, prevented the operator from severely injured. Cause: It appears certain that the brakes of the trailer were not locked, (probably because the air pressure had bled off) and that the wheels had not been adequately chocked. Additionally, because of the forward position of the tandem wheels, witnesses report that as the docker entered the trailer, the front end of the trailer tipped up, dislodging the chocks. Preventive Measures: Asoftenas this "classic" trailer acci dent has occurred, this accident points up the need to reiterate what is considered to be the standard operating procedure. 1. All trucks should have brakes locked prior to loading. It must be assumed that if a trailer has been detached from the cab for several hours that the air pressure has probably bled off. 2. Wheel chocks (the type with a beveled edge) should be placed under the trailer road wheels. The chocks should be chained to the dock to have them readily available. 3. Prior to entering a detached trailer, the docker operator should insure that the road wheels are in the most rearward position. If they are not, the rear of the trailer should be supported as with a trailer jack 4. When loading an empty detached trailer, the front of the trailer should also be supported to increase trailer stability. "A" Frames or equivalent are recom mended. CASE HISTORY NO. 1784 HuS in Sulfur Cars Description: An operator was overcome by HaS gas and fell down the tank car unloading dock stairway, sustaining disabling injuries. At approximately 12:05 a.m., the operator started making preparations to unload a sulfur car. The car was spotted on the loading dock. He proceeded to loosen the bolts around the dome of the car. He did smell some Hl>S gas as he was performing this operation. He proceeded to follow the normal practice of opening the dome cover and propping a bolt underneath the cover. This allows the car to vent, while being unloaded. In the process of placing the bolt under the cover, he inhaled hydrogen sulfide which was being emitted from the dome of the car. He then grabbed his wrench and oil can and started running for the stairs leading to ground level. Proceeding down the stairs he passed out and fell down the stairs to ground level. A shift electrician noticed him leaning against the tank car at approximately 12:10 a.m. The injured yelled at the elec trician who stopped the truck he was driving and went to investigate. He found the injured badly bruised, dazed and bleeding from a head injury. Cause: The injured stated that the quantity of HaS emitted from the dome of this particular car was much more than any previous sulfur car he had ever unloaded. The committee attempted to gather some information of HaS formation in sulfur cars. Following is a summary of the information collected. Sulfur is produced by two completely different methods: mining of the pure elemental sulfur and as a by-product of oil refining. Refinery sulfur is distinguished from mined sulfur by its bright yellow color. Mined sulfur is darker. Hydrogen sulfide can be generated by organic contamination of the sulfur. This is most common in sulfur mined in the elemental state. Refinery by-product is produced by S7 -- CMA. 048771 refining an SO2 hydrogen sulfide gas stream. Hydrogen sulfide is soluble to a limited extent in sulfur. The solubility of hydrogen sulfide increases as the temperature of the sulfur increases. Solubility of H2S at I65C is .13 gmx per 100 gms of sulfur. As the car cools. H:S comes out of solution and collects in the vapor space. Problems with the hydrogen sulfide to sulfur dioxide ratio or an abnormally high tempera ture can produce sulfur with a high amount of HrS in the product. Retinery produced sulfur normally contains a much higher amount of hydrogen sulfide in the product than does the mined sulfur. This has been substantiated by discussion with sulfur unloaders and suppliers of sulfur. The plant had been receiving much mined sulfur but the car that was involved in the incident contained sulfur pro duced from a hydrogen sulfide/sulfur dioxide gas stream. The department foreman stated that only two or three of the refinery-produced sulfur cars had been received in the department. This would explain why the injured stated that the H2S evolution from this car was higher than any car he had previously unloaded. It is doubtful that he has ever unloaded a car of sulfur produced from a hydrogen sulfide stream, The foreman stated that operators had been trained to watch out for hydrogen sulfide while unloading sulfur cars and to always "stand upwind" while removing the dome. This was normal plant procedure at the dock and the acid unloading dock. Sulfur is unloaded by tank cars only in these two areas Sulfur tank cars are equipped with vents which tend (o become inoperative. Sulfur may splash into the vent and solidify, or sublime and plug the vent. Preventive Measures: 1. Place on order permanent signs warning of the hazard and requiring mandatory respiratory protection. 2. Air line respirators connected to breathing air should be used by any personnel while opening the dome on sulfur cars or cracking the crust of a car. The breathing air should be checked by the department foremen or supervisor to prevent any possibility of other gases being used in error. 3. Sulfur cars with sulfur spills on the bolts surrounding the dome should be rejected. 4. The feasibility ot incorporating a minimum hydrogen sulfide concentration into the sulfur raw materials specifications and the possibility of hydrogen sulfide removal by suppliers before shipment should be inves tigated. 5 The rails at both loading docks should be grounded. 6. Operating instructions should be revised to warn of the hazards of opening sulfur cars, and Scott Air Paks should be provided for emergency rescue in the vicin ity of the loading docks. CASE HISTORY NO. 1785 Acid in Wrong Tank Description: Through miscommunications a tank truck of hydrochloric acid was unloaded into a large storage tank for concentrated sulfuric acid. After about half of a 3.000 gallon tank truck load of hydrochloric acid was unloaded into the 36 foot diameter by 18 foot high storage tank. a violent explosion occurred, which broke fill and vent lines, buckled the bottom plate and some of the top plates, and raised the tank several inches from the ground. The top was broken open permitting acid fumes to escape. For tunately. no one was injured, but there was considerable loss, both to the tank and from lost production. Pre\enuve Measures: 1. Foreman will meet truck, check bill of lading, and accompany truck to proper unloading facility. 2. Foreman and man who will transfer the acid will sign bill of lading at unloading facility. CASE HISTORY NO. 1786 Methylation Explosion Description: An explosion occurred in a pilot plant vessel after a methylation involving dimethyl sulfate had been successfully completed. After the reaction had taken place at II0C, all jacket services were shut off and the batch allowed to remain in the reactor with agitation. The explo sion took place about I'A hours later. Investigation found that during the latter phase of the stirring process at 100C. a slight decomposition of the mixture occurs with a slight heat rise. This had not been detected previously. The batch in question was believed to have heated up gradually to 150C where it started to boil and decompose rapidly. Preventive Measure: This occurrence emphasizes the need for careful stability studies to determine the presence ot exotherms and the parameters of controllable processing. CASE HISTORY NO. 1787 Fluorescent Light Fixture Accident Description: Following a normal weekend, chemists returned to their laboratory on Monday morning to find that several glass panels in a row of fluorescent lighting fixtures had fallen out onto the work space below . The fixtures affected were a row of five 4-ft. modules flushmounted-in the ceiling and having four 1 - ft.-square glass panels per module. In each module, the central two glass panels had dropped out. Also, in each module, a transverse wire, designed to prevent the two sides of the fixture from spreading, was broken. The first conjecture was that maintenance men working in the space above the suspended ceiling must have used the fixtures for a walkway and that the resultant pressure spread the sides of the luminaires, allow ing the glass panels to pop out. Inquiry revealed that no such maintenance work had been performed; therefore, another explanation was needed. Cause: The ballast in one of the fixtures had failed, and an electrical lead had burned off at the point where it entered the ballast. These thirteen-year-old ballasts were not ther mally protected to de-energize the lamps in case of over heating. Consequently, it was conjectured that a failing bal last did overheat sufficiently to vaporize some of the asphalt material in the ballast. Since the void within this line of - 58- CMA 048772 ji^iires is reasonably gas tight, the vapor content increased CASE HISTORY NO. 1789 t^H|t reached a combustible mixture with the air inside tlSiRid. A simultaneous short in the electrical lead could Ethylene Glycol Pump Ruptures then have ignited a low-level explosion w'hich propagated along the length of the luminaires. The resultant pressuriza Description: The housing of a centrifugal pump ruptured tion against the sides and glass panels would have been with explosive force. The force of the rupture threw part sufficient to break the restraining wires and force the sides of the pump housing into the water ring pump reservoir, far enough apart to drop the two middle glass panels to causing water to flow out on the floor. The suction line the floor below. to the pump was sheared, emptying the contents of the tank onto the floor. The pump housing was knocked com Preventive Measure To remove the threat of a repetition pletely free of the concrete pad. Three anchor holts and of this accident, a program was established for exchange one leg of the housing were sheared. The armature shaft of the ballasts in all fixtures torthe newerthermally protected of the pump motor was dislocated to the rear, breaking ballasts. It is believed this change wall prevent the continued the motor housing in the front and rear. Ethylene glycol heating that would be necessary to gasify the ballast ma vapors were heavy in the room. terials. The polymer operator, and a shift electrician, were first on the scene. They had heard the noise from the first floor U.S. Atomic Energy Commission Case History hall. They observed heavy ethylene glycol vapors through the windows in the door and entered as soon as the vapors CASE HISTORY NO. 1788 had cleared enough for safe passage. The operator called the Control Room to report the problem, and the electrician made sure the pump motor was switched "OFF'' to prevent Adjustable "A" Frame possible fire. The polymer foreman immediately directed efforts to stop the ethylene glycol and water spillage and Description: Two men were trying to lower a gantry "A" called for the assistance of the night superintendent. frame, when the leg suddenly telescoped and the frame The contaminated ethylene glycol pump which ruptured toppled over onto the floor. As it fell, a part of the frame is normally used as a spare. At the time of the rupture, struck one ot the men's legs and inflicted a severe laceration. the suction and discharge valves were closed, and the pump The gantry "A" frame consists ot four telescoping legs was thought to be off. The field reading sheets list the which permits changing the height of the frame. An "I" pump as "OFF" as late as the 4 to 12 shift on the previous is suspended at each end from the tops of the two day. Investigation revealed that the pump switch was in in pairs, which are hinged onto the `T' beam for the "RUN" position in the Control Room. Most of the adjustment. The spread of the legs can be adjusted by a witnesses state that the field switch was in the "RUN" telescoping tube between the bottoms of the legs. The legs position at the time of rupture. This opinion is not unani are also braced to prevent them from moving inward beneath mous, however. The three fuses supplying current to the the "1" beam. The "I" beam supports a 3-ton hoist which motor were found to be blown shortly after the rupture. can roll from one end of the beam to the other. A "U" Witnesses report that the pump casing was hot (water splash holt on the top center of the "1" beam permits the gantry ing on casing was vaporized rapidly), and the pump motor to be suspended by a hoist or tackle block when adjusting was slightly warmer than ambient temperature immediately the height. after the incident. The "A" frame as a whole weighs around 1,000-lbs. The control room operator did not notice an audible alarm Investigation revealed that the top of the gantry had not indicating stoppage of the pump motor at the time of the been suspended, as suggested by the manufacturer, before incident. Shortly after the incident, the panel alarm light adjusting the height. When one leg dropped, the 3-ton hoist was observed, indicating that the pump was not running rolled to the lower side, flipping the whole unit over. at that time. If the pump was actually running immediately Furthermore, several cotter keys were missing from the before the incident, its audible alarm was most likely spring loaded bolts which lock the legs in position. obscured by other alarms sounding at the same time. Other alarms sounded immediately after the incident, directing Preventive Measures: Following the accident these recom attention to other vessels. The acknowledge button which mendations were agreed to: silenced these alarms would have also silenced the pump I. Everyone should be instructed in the safe and proper alarm. use of equipment. The pump which failed was a KSB centrifugal cast iron 2. The "I" beams should be marked in large letters: pump. The vendor stated that no work had been done to "Support Before Adjusting." establish empirically the pressure needed to rupture a pump 3. The hoist should be secured before adjusting or mov of this type. Plant records show that this pump had been ing the "A" frame. static tested at 357 psig (at room temperature). If the vapor 4. The cotter pins should be removed from the stabilizing pressure of the pump contents had reached 357 psig. the legs and padlocks installed tn their place. (The pad temperature would have been about 500F. No data on the locks should be chained to the equipment.) strength of class 35 cast iron at such elevated temperatures Scheduled inspections should be made to assure that is available, therefore, no precise estimate of the pressure the equipment is safe to operate. required to rupture the pump under these conditions can 6, The vendor should be contacted for his advice. (In he made. No evidence of a faulty or cracked pump housing novations are reported to have been made to the origi was found. The pump can develop 150 psig head per vendor nal design.) literature. -59- CMA 048773 The committee found no evidence to indicate that the incident was caused by ignition of an explosive mixture inside the pump. The field switch on the pump was a Crouse-Hinds three position switch. Investigation revealed that this switch and approximately 67 other similar switches in the area do not have labels to indicate the position of the switch. The operators must remember that left position is "START," center position is "RUN," and right position is "STOP." It was also determined that the switches have a position lock mechanism w hich could be misunderstood and misused. Detailed examination of the switches also revealed that some of the sw itches can be rotated 360 which could cause con fusion. Came: Operating error. Inadequate identification of electri cal controls. 1. Basic Cause The committee concluded that the most likely cause was overpressurizing the pump due to accidental op eration of the pump with both suction and discharge valves closed. The mechanical energy of the pump heated the liquid inside the pump until the increasing vapor pressure and temperature caused the pump to rupture. 2. Contributing Cause No identification of lever positions on the CrouseHinds field switches. Preventive Measures: 1. Provide drainage facilities and adopt a drainage proce dure to drain CEG pumps when they are shut down. 2. Each Area Superintendent will have the pump equip ment in his area audited in an effort to detect and correct potential problems similar to those reported herein. 3. Add drain valves to the suction of the CEG pumps under the tank to enable controlled depressurization of the hot liquid in preparation for maintenance. 4. Acquaint all operating personnel with potential hazards involved in operating any pump with closed suction and discharge valves. CASE HISTORY NO. 1790 Moving Equipment Description: An operator sustained a partial amputation of his finger when it was caught in a conveyor belt drive. The injured had noticed the product conveyor belt from No. 1 cooler was not moving. He reported it to his foreman, who obtained the services of two electricians to determine if a fuse had burned out. The electricians found the fuse to be o.k. and in checking the switch room found a load to be on the line. One of the electricians and the production shift foreman then checked out visually the motor for the belt drive on the conveyor. By the use of a flashlight, the two men could tell the motor, approximately eight feet off the floor, was running but the belt was slipping in the motor belt sheave. The shift foreman explained to the operator that the mote was running but the belt was slipping and he used a flashhgl to point this out. While the operator was obtaining a laddt for a closer look, the shift foreman went into the bag rooi a few feet away to review his production requirements an sec if he could wait until maintenance arrived at 8.00 a.n to get the unit repaired. The operator placed the ladder and climbed up near tf west side of the motor and reached his right hand behin the metal belt guard to determine if the belt was movin; At the precise moment he touched the belt, the operati said the belt apparently began moving and pulled his rigl hand toward the motor pulley. His right middle finger w; caught between the belt and the pulley, amputating approx mately two-thirds of the distal phalanx. Cause: 1. Unsafe act (consciously putting hand behind guar onto belt drive). 2. Inadequate guarding (belt guard not enclosed on bac side). Preventive Measures: 1. Employee Education -- Review this injury at a safety meetings, emphasizing the hazards involve with guarded equipment CASE HISTORY NO. 1791 Electrical Description: A contractor's electrician received a fatal elec trical shock while working in a company plant. He am a co-worker were installing a temporary line for an eiectrr fan. The power source was a 220-volt junction box in 19 inch crawl space of a newly installed false ceiling ii a building which was being renovated. After running thi wire and making the connections at the box, one of tht electricians climbed down to check the circuit at the othe end. When he called to the man in the crawl space tha the fan was not working, he received no response. He thet made several other checks and on instructions from a super visor went with another electrician to see what was goin on in the crawl space. They found the electrician who mads the connections at the junction box unconscious. He wa; pulled out and given artificial respiration but to no avail and pronounced dead on arrival at the hospital. Preventive Measures: This tragic accident again underscores the hazards of relatively low voltage electricity. It is not known whether the fatal shock was caused by 110 or 220 volts. Certainly it is inadvisable to work in cramped quarters on live circuits and especially, as in this case, when it was unnecessary. The service being provided certainly was not critical. It is also unlikely that switching off the circuit which supplied power to the junction box for a few1 minutes would cause no more than a possible minor inconvenience. There are occasions when it may be necessary to work on live circuits. Only electricians who know the hazards, -60- CMA 048774 f ihe-protection, and other precautions necessary, should ever ;^^nt working on energized circuits. These men by trainiSBd experience appreciate that failure to take a necessary precaution may be their last. CASE HISTORY NO. 1792 Collapsed Racks 2. Use only stainless steel LPG specification hose for LPG service. 3. Install fixed water spray protection on all of the load ing spots handling LPG. 4. Investigate the need for installing additional fire monitor hydrants to facilitate fire emergency opera tions. 5. Conduct occasional problem-type fire drills at night to determine emergency manpower and equipment requirements. Description. While a man was operating a Tennant Sweeper in an aisle between storage racks he swerved the machine to avoid striking a pallet which protruded into the aisle. The rear of the sweeper struck a vertical leg of the pallet rack. He heard a "cracking" noise above and as he looked up he noticed the rack was starting to sway. The rack section collapsed burying the sweeper with product. Fortunately he was able to run clear of the collapsing section. Cause: 1. The pallet racks had been abused by fork lift trucks, bending some of the vertical members. 2. The racks were also overloaded. Pm vennve Mea sitres: 1. Better supervision and retraining of fork lift truck operators. Careful loading of racks and avoidance of overloads. Frequent inspection of rack members. CASE HISTORY NO. 1793 Rupture of Transfer Hose Description A potential fire incident occurred when a 1 'A" diameter steel braided hose ruptured during a transfer opera tion involving the unloading of 9,000 gallons of propane from a tank truck. The loading rack operator immediately valvcd in the hydrogen methane supply used to pressurize ' the tank truck and the 2" valve at the propane storage tank. The heavy vapor cloud near the rear of the tank truck prevented immediate closing of the truck unloading valve. The tank truck's excess flow valve did not operate, pre sumably because of the flow restriction imposed by the small diameter unloading hose. The fire alarm was turned in by an off-duty Shift Super visor who also alerted fishermen located along a countryroad 500 feet south of the gas release. He instructed them not to operate their vehicles and to refrain from smoking. Water spray from one fire monitor nozzle and four fire hose streams provided cover for three operators in protective clothing and self-contained breathing equipment who entered the area and valved off the truck. ^Approximately 3,000 gallons of propane escaped. Wentne Measures: 1. Use unloading hose having flow characteristics com mensurate with the shutoff setting of the tank truck excess flow check valve. CASE HISTORY NO. 1794 Laboratory Freezer Fire Description: An explosion and fire caused extensive damage in an analytical laboratory when flammable vapors ignited in the storage compartment of a domestic-type vertical freezer. At the time of the incident, the freezer contained bottled samples of various naphtha fractions, uninhibited styrene, inhibited acrylonitrile, and numerous one dram vials of miscellaneous reference samples in wooden racks. The source of ignition is presumed to be the temperature control device located in the freezer storage compartment. Three automatic sprinklers operated and controlled the fire which was later extinguished by fire squad personnel. Electronic instruments located in the laboratory were undam aged. The laboratory was unoccupied at the time of the incident. Preventive Measures: 1. The use of domestic-type freezers and refrigerators for storage of flammable liquids will be discontinued immediately. 2. All domestic-type freezers and refrigerators currently used for storage of flammable liquids shall be modified in accordance w-ith NFPA Standard 56C. Paragraph 13 (Laboratory-Safe Refrigerators). 3. Materials which may detonate or explode by self-reac tion when not refrigerated shall be stored in refriger ated equipment remote from all laboratory work areas. 4. Storage regulations will be posted on the door of all refrigerated equipment in which flammable materials are stored. 5. Conformance to storage regulations will be monitored by the laboratory safety committee inspection team. CASE HISTORY NO. 1795 Laboratory Explosion -- Peracetic Acid Description: An attempt was being made to prepare about 600 grams of an anhydrous solution of 25 percent peracetic acid in acetic acid as solvent. The starting material was a commercial mixture of peracetic acid and hydrogen perox ide in acetic acid. The solution as supplied is actually a mixture in which the reversible reaction: acetic acid + hydrogen peroxide " peracetic acid + water has come to equilibrium. The mixture also contains one -61- CMA 048715 percent sulfuric acid as a catalyst to assure rapid equilibriation. According to plan, acetic anhydride was added to react with, and thereby remove, the water. Then, the sulfuric acid was taken out by adding barium acetate. Finally, the mixture was vacuum distilled awaj from the barium sulfate. The distillation proceeded smoothie at a temperature of about 40'C. When about half of the material had distilled, the chemist walked a short distance away for a smoke. At this time there was a terrific explosion which broke and distorted both the transite walls and safety glass window of the fume hood in which the apparatus was located. The glass distillation apparatus was completely disintegrated. The chemist had been fortunate enough to walk away at just the proper time to prevent personal injury. This particular preparation had been carried out previously a number of times wuthout any difficulty. Cause. Investigation revealed that the directions for carrying out the operation had become garbled in transmission. As a result, the sulfuric acid catalyst was mistakenly removed before the addition of the acetic anhydride instead of after. Also, the reaction temperature was held below ]5C. Both of these changes would cause a much slower rate of reaction of the anhydride with the water. It seems highly probable that a substantial concentration of anhydride was present in the mixture when the distillation was started. Acetic an hydride and peracetic acid react readily to form acetyl perox ide. This compound has a notorious reputation as an extremely sensitive explosive. Under the influence of the heating mantle and the agitation of boiling, it could have acted as an initiator for the detonation of the peracetic acid. Preventive Measures: 1. A written set of detailed directions has been prepared for the lab preparation. Lab supervision will make sure the directions are understood, and followed exactly. 2. The reaction mixture will be analyzed for the con centration of the various components before distilla tion is started. Any deviation from normal will be considered the signal for deactivation and disposal of the batch by dilution with large quantities of water. 3. The hazards of working with peroxygen chemicals have been reviewed with personnel, and the necessity for proper handling has been re-emphasized. CASE HISTORY NO. 1796 Methanol Ignition Causes Centrifuge Fire Description: At about 2:00 a.m., flames were seen coming from the outside back of penton-lined centrifuge. An instant later, an explosion blew out the sight glass and blew open the access door on the top of the centrifuge. Flames erupted through the open lid and around the outside of the centrifuge. Within 5-10 seconds, the flames had been extinguished by two operators armed with dry chemical fire extinguishers. No personnel were injured, although the operator attend ing the centrifuge was blown back against the panel board. The man-way top of the centrifuge will have to be replaced. Three glass pipes were broken and about 10% of the trans lucent. green blowout panels in the building were blown out. Cause Examination of the equipment after the explosion indicates that the incident started outside ihe centrifuge. The drive belts were rubbing a copper grease tube, and the friction heat caused by this, apparently ignited a methanol-air mixture spilled outside the centrifuge. The flame burned a hole in a rubber boot just under the centrifuge and allowed air and flames to enter the basket, presumably causing the explosion. Although the centrifuge was blan keted with nitrogen per procedure, it lacked capacity to overcome the hole in the boot. Preventive Measures: The design of the copper grease tube will be modified to remove it from direct access to the drive belts. The inerting procedure will be re\ iewed to insure its adequacy. A nonflammable boot will be purchased, if possible. CASE HISTORY NO. 1797 Fire Caused by Fuming Nitric Acid Description: About 5:45 p.m., the Shipping Department's sprinkling system was activated and controlled a fire until the City Fire Department responded. Investigation revealed the source of the fire to be fuming nitric acid. Several bottles of this acid, packed in metal containers, were placed in a wood box truck and left standing over the holiday weekend. Apparently one of the bottles was cracked, allowing the acid to leak out and eat through the metal container. Contact with the wood box truck and other materials and chemicals, flared into a fire of sufficient heat intensity to activate three sprinkler heads, automatically calling the Fire Department, Preventive Measures. This incident calls attention to the following: 1. Later similar incidents indicate a production lot of faulty bottles. This is under further investigation. 2. The importance of supervised sprinkler systems can not be over emphasized. There is no doubt that the control provided by this system along with the auto matic alarm sent in to the City Fire Department, very likely saved the building. 3. It reminds us that although nitric acid is non-combus tible, it is dangerously reactive with many materials. Containers must be protected from physical damage. It must be separated from metallic powders, carbides, hydrogen sulfide, turpentine, organic acids, and all combustible, organic or other readily oxidizable materials. CASE HISTORY NO. 1798 Mechanic Has "Close Call" from Chemical Exposure CMA 048776 Description: A shift mechanic w'as attempting to connect a coupling hose to the bottom of a railroad tank car filled with epoxy and epichlorohydrin. While in the process of mo\ ing the discharge plug, which was only "hand tight", e material poured out splashing the mechanic on the arm. leg. and chest. He immediately left the area, removed his clothes, and scrubbed the exposed areas. Due to the quick action on his pari, no injury resulted. Cause The tank car arrived in the plant with the foot valve in the open position. It is worth noting that the supervisor had to use a sledge hammer to open the rusted cover to gain access to the foot valve control on top of the ear. Other contributing factors were poor lighting in the area, working in close quarters, and working without proper per sonal protective clothing. Preventive Measures: 1. In future operations of this nature, the following items of protective clothing will be worn: Rubberized suit (top and bottom). Goggles. Gloves. Rubberized boots, and Bump hat. 2. A portable light will be provided for use in the area. 3. All external lighting in the area will be checked and "burned out" bulbs replaced. 4. The female portion of the hose coupling will he reversed to allow for easier coupling. 5. A derailer will be placed on the track between the tank car spot and the main track after the tank cars are spotted. Also, the ears will be chocked to prevent inadvertent movement. 6 The shipper will be requested to install external control valves on cars prior to shipment. 7 A mechanic will check prior to removing the discharge plug to see that the foot valve and external valves jre dosed. 8. A study will be initiated to check the feasibility of permanently raising the hose over the ear so that the initial handling of the hose is eliminated. 9. A job safety analysis will be written and this incident used as a topic for discussion at safety meetings. CASE HISTORY NO. 1800 Eruption of Molten Metal Description: A furnace containing molten aluminum was being used for experimental purposes as a heat source. The molten metal suddenly erupted from the furnace striking the employee on the foot. Hospitalization became necessary for skin grafting. Cause: Lack of adequate safety analysis prior to starting experiment. Pres entire Measures Re-emphasis given to need for formal safety review of procedures and equipment for experiments. CASE HISTORY NO. 1801 Hydrofluoric Acid from "Empty" Line Description: Three employees were re-installmg spray nozzles in hydrofluoric acid contact condenser. Because they had locked out and tagged the appropriate pump starters and valves the previous day, they assumed that the system was empty and did not wear full acid suits as they had the day before. While they w'ere replacing one nozzle, a sizeable quantity of liquid HF ran out onto one employee. Burns on his knee, shin, and instep required hospitalization for skin grafts. Cause: Assumption that line would remain free of acid. Preventive Measures: Importance of wearing protective clothing during entire job. and need for alertness to booby traps of so-called "open" systems have been re-emphasized. CASE HISTORY NO. 1799 Discharge from `Empty" Line Description: Nitric oxidizer and discharge piping had been emptied and depressurized preparatory to replacing the bon net of a gate valve in the discharge line. During replacement of the valve bonnet, the closed valve gate was disturbed, allowing hot acidic water to spray onto ankles of supervisor who had entered the area. Cause Adequate drainage for the line had not been pro vided. Pres enure Measures The repair procedure will be more specific concerning adequate line drainage, and roping off of similar repair areas will be mandatory. CASE HISTORY NO. 1802 Chemical Transportation Emergencies The following is excerpted from Safety Recommendation R-71-38 published by the National Transportation Safety Board, Washington, D.C. and forwarded to all State Fire Marshals. "The National Transportation Safety Board issues the following information and warning as an advisory, pending the completion of the investigation and further analysis of the facts and circumstances of the derailment of Missouri Pacific Railroad Company Freight Train No. 94 at Houston. Texas on October 19, 1971. "This freight train derailed at Houston. Texas. As a result, 16 cars piled up in the general derailment area. Included were six tank carloads of vinyl chloride, three of fuel oil, one each of acetone, butadiene, and formal dehyde. Vinyl chloride, which escaped from a damaged 48.000-gallon tank car. ignited immediately following the initial derailment. -63- CMA. 048777 "The Houston Fire Department responded to the scene within a few minutes after the derailment occurred and took steps to control the fire with water. Forty-five minutes after the initial derailment, a second car, containing vinyl chlo ride. ruptured \ lolently. This abrupt explosion and the subse quent tire resulted in fatal injury to one fireman and burns or iniuries to approximately 57 other firemen, reporters, photographers, and spectators. Large sections of a tank car were lound approximately 400 feet from the derailment site after the explosion. "The circumsiancex of this accident are markedly similar to those of the accident that occurred at Crescent City, [Hire's, on June 2 1. 1970. At Crescent City, a 15-car derail ment resulted in the initial release of propane from one ot the nine cars containing this commodity. Fire ensued movdiately thereafter, and fire departments responded to tits ssene and attempted to fight the fire. Subsequent explosior.s occurred during a period ranging from approximately i to 4.2 hours after the initial derailment. Large portions of the involved tank cars ``rocketed" up to 1,700 feet from the accident site. Sixty-six firemen, reporters, and photog raphers were injured as the result of the subsequent ex plosions. "The Safety Board has investigated other railroad acci dents involving hazardous material where tank cars have exploded and rocketed. A synopsis of the pertinent details of these accidents is included as Appendix No. 1. "Generally , those accidents that have resulted in casual ties to emergency service personnel or onlookers have had two distinguishing characteristics, namely; 1. Several tank cars lay adjacent to one another in the wreckage. 2. Fire ensued, enveloped one or more tank cars, im pinging upon other relatively undamaged tank cars containing hazardous materials. "These accidents demonstrate that whenever a railroad accident inxoKing several adjacent tank cars occurs, the presence of tire substantially increases the probability of additional flareups or explosions. The reduction in property damage achieved by fire suppression methods used in past accidents, has been generally insufficient compared to the risk assumed of injury and death when acting whth inadequate or improper information as to the contents of tank cars. "The risks, however, should be studied as closely as possible in the particular circumstances present, before initiating fire suppression efforts to save the product or other property. Necessary information for this decision-making process should include the rapid identification of all commodities involved, the determination of the firefighting methods by which the risks associated with these commodi ties can be controlled, and whether the resources needed to cope effectively with the situation are available. "In the absence of the information necessary for an Ievaluation of the risks of explosion or rocketing in a fire involving several tank cars, a prudent course of action may be the complete evacuation of the area within a radius of 2,000 feet. Exposure of emergency personnel to abrupt flare- ups or explosions can be kept to the absolute minimum by this method when no other persons or minimal property arc at risk. Under no circumstances should spectators be allowed in the potential danger radius of 2.000 feet. However, it is not possible to give all-inclusive advice con cerning the degree of risk which should be taken to fight the fire in such accidents because there are so many variables involved. For example, there may be tank car fires in the vicinity of hospitals, schools, or other occupied premises which cannot be evacuated quickly. "Research work to correct the problem of exploding and rocketing tank cars has been underway in the Department of Transportation and the railroad industry since shortly after the accident at Laurel, Mississippi, on January 25, 1969. The problem is potentially reducible by technical changes which are under study. "Because the Safety Board believes the need for addi tional knowledge for the control of tank car fires is crucial, we held a public hearing in Houston, Texas to gather facts concerning the derailment, fire, and explosion of Missouri Pacific Train No. 94 that occurred October 19, 1971. "Therefore this information and advisory warning is issued as an alert to the potential hazards of tank car derailments." EDITOR'S NOTE: Commenting on the causes of tank rup tures of the above type, a flammable liquids specialist states in part, "There are no known cases of fire involving a vinyl chloride tank causing an over-pressure rupture of the tank due to polymerization of the vinyl chloride. Apparently, emergency relief valves usually can handle polymerization pressures. "From the best information we have to date, the vinyl chloride tank car incident near Houston was caused by flame contact on the vapor space of the tank, causing overheating at one spot with sudden failure and release of the fireball. This has happened with propane and gasoline etc. "There are materials, styrene for example, which poly merize and could cause over-pressure rupture of the tank due to emergency relief devices not being able to handle the polymerization temperature and pressure conditions existing during a fire." MCA plans to revise certain of its Chem-Cards (including CC-46 Vinyl Chloride) and Cargo Information Cards to warn against the probability of tank car rupture when a relatively undamaged tank car containing hazardous material is exposed to fire. CASE HISTORY NO. 1803 Sulfur Dioxide Release During Tank Car Cleaning Description: A substantial quantity of sulfur dioxide was released to atmosphere over a five-hour period when water was introduced to a supposedly empty tank car. -64- CMA 048778 APPENDIX NO. 1 SYNOPSIS OF RAILROAD TANK CAR HAZARDOUS MATERIAL ACCIDENTS INVESTIGATED by The RATIONAL TRANSPORTATION SAFETY BOARD Date of Accident Location Number of Cars in General Derailment Number of Tank Cars Derailed Time Between Initial Derailment and Subsequent Explosions Contents of Tank Cars No. of Fatalities No. of Inlurles Jan. 1, 1968 Dunreith, Indiana 14 6 45 Minutes Acetone, cyanohydrin, methyl methacrylate vinyl chloride, ethylene oxide 0 5 Jan. 25, 1969 Laurel> Mississippi 15 15 Immedlate Liquefied petroleum gas 3 32 Feb. 18, 1969 Crete, Nebraska 31 3 Immed iate* Anhydrous a mmonia 9 53 Sept. 11, 1969 Glendora t Mississippi 15 June-21, 1970 Crescent City* Illinois 15 10 5Y hours and 16 hours 9 1 hour to 4Y hours Vinyl chloride and fuel additive Propane 0 0 1 66 Oct. 19, 1971 Houston, Texas 16 12 45 Minutes *No fire. Brittle fracture of tank car in crash allowed instantaneous release of entire cargo of ammonia, producing poisoning. However, similar hazard in fire exists. Vinyl chloride,, fuel oil, acetone, buta diene , formaldehyde 1 37 Types of Casualties Firemen and police Distances Portions of Tank Cars "Rocketed" 700 feet Residents 1,600 feet Residents 200 feet and transients Power company 850 feet serviceman Firemen, reporters photographers 1,700 feet Firemen, 400 feet reporters, photographers, spectators 0 4 S T 7 9^ An 8,000-gallon tank car. formerly in sulfur dioxide ser vice, was sent to the plant car repair shop for cleaning in preparation for a change in service. Although the car w as weighed by the plant when received and noted to contain material in excess of the normal heel, this information was not transmitted to responsible supervision. In preparation for washing, the car was vented via a one-inch hose to a water-filled drain pit. After a short period, venting ceased and it was concluded that the car was empty. Two one-inch water hoses with "Chicago" hose couplings were connected to standpipe valves on the car dome and water was introduced. About an hour later, sulfur dioxide fumes were seen discharging from the car dome. Available respiratory protective equipment at the site was inadequate to permit immediate access to the car dome. It was later determined that both water hoses had un coupled and liquid sulfur dioxide was discharging from the standpipe connections. The couplings had not been pinned, and it is theorized that sulfur dioxide vaporization was suf ficient to cool and shrink the gaskets, allowing the couplings to separate. The reason for the cessation of venting before water was applied was not positively determined but may have resulted from a drop in vapor pressure due to self refrigeration. The plant emergency procedure was implemented and affected areas were evacuated. No injuries resulted from this incident. Came: Inadequate communications -- inadequate operating procedures. reventive Measures: All cars to be washed anchor entered will be weighed immediately before being brought into the car repair shop. Reasonable minimum heel weight will be determined and used to compare weights of empty cars. Car cleaning methods will be reviewed and rewritten in ureater detail. the adjoining cubicle, killing them instantly. The force ot the explosion is estimated to be the equivalent of 13 lbs. of TNT. Cause: Special laboratory investigations conducted after the explosion revealed the existence of a two phase system during the early stages of the batch reaction. The two phases were difficult to detect because they had very close specific gravities and retractive indices. The peroxide-rich phase becomes extremely shock-sensitive between 10 and 307of the acetic anhydride addition (about 4,000 gm-cm or equivalent to nitroglycerine). No shock sensitivity was detected below 57 and above 407c acetic anhydride addition. Differential Thermal Analysis also indicated thermal decomposition could be initiated above 50C in the area of peak shock sensitivity. However, reaction temperatures were maintained well below- this. Preventive Measures: 1. The Reactive Chemicals Committee at the site has initiated efforts to develop improved standards and procedures to detect "trigger" situations in suspect reactions where raw materials and final products are not shock-sensitive themselves. This will require increased testing and study before the Committee will approve such projects for Pilot Plant operation. 2. Where potential hazards are suspected, personnel will be protected by explosion resisting cubicles and remote operation until ultimate safety precautions can be determined. 3. All Pilot Plant projects will include a member of the Reactive Chemicals Committee on the pre-startup safety review to ensure adequate data has been obtained on reactivity and conformance to the improved standards and procedures. 4. The chemistry of the project which required the peracetic acid is being investigated further to see if peracetic acid can be eliminated or w-hether commer cially available (lower strength) material could be used. CASE HISTORY NO. 1804 Pilot Plant Explosion -- Preparing Peracetic Acid Description: Peracetic acid was being prepared by a batch process in a 20 gallon glass-lined jacketed reactor equipped with a standard agitator. The process involved adding acetic anhydride slowly to a stirred solution of hydrogen peroxide in methylene cldoride. This procedure was based upon a study ot research literature which reported that "mixtures containing less than 3091 by volume of commercial 907 hydrogen peroxide in many inert solvents are not explosive." The process had been performed repeatedly w ithout incident on a laboratory scale. Two previous batches had been produced at the pilot plant prior to the explosion. Whcn approximately 107 of the acetic anhydride had ^en pumped in by a proportioning pump, the contents of the reactor (about 40 lbs. or 3Vi gallons) exploded. The wall of the cubicle was blown against two employees in CASE HISTORY NO. 1805 Line Cleaning Description: The department was producing SALP and the operator was dropping a batch from the reactor to the mixer. SALP coming out of the reactor has a pH of 4, and a temperature of 133C with a malted milk appearance and a consistency of molasses. The operator could not get the batch to drop into the mixer from the reactor, in an attempt to clear the drop line, he opened the steam valve and blew steam into the line. This is the standard procedure. He met with little success. The batch still would not freely drop into the mixer. The operator then contacted the foreman w'ho instructed the operator to hook a steam hose into the line tor additional steam pressure. They then alternately blew- steam into the drop line and up into the reactor. The foreman then instructed the operator to turn the steam off. --66- CMA 048780 close the main valve under the reactor and close the drop valve. The foreman then opened the valve to the sewer __ der to vent any pressure that was still left in the line. The foreman could not remember whether he opened the drop line valve or not. He then started to unscrew the cap to clean out the port. He had decided to rod into the line in an attempt to clear the blockage. He turned the cap and pressure puffed out the sides. He stepped back until it stopped. He approached the cap and just as he got over it, the cap blew off, spraying hot SALP on his face and hands. He was wearing safety glasses and had a shield in his hand covering the cap. The exploding cap knocked the face shield out of his hand completely flattening the face plate. The operator rushed the foreman to the eye bath, which, was seven feet from the clean out port and flushed his face and hands with water. The injured employee was then taken to the hospital and was subsequently admitted. It was the doctor's firm conviction that had he not had safety glasses on, he would have been permanently blinded. Cause: Inadequate design. (A pressurized line which could not be relieved safely.) Preventive Measures: 1. Raise the clean out and install a permanent rodding device so that the line can be cleaned, without taking the cap off. 2. Install a bleed-off valve at the bottom of the clean out port so that the drop line can be pressurized safely. . Install a bleed-off valve between steam valves and quick couplings on steam hoses within the plant which are hooked up into other lines. 4. In addition to above recommendations, maintenance and production supervisory personnel are directed to set up for an indefinite time, an approval-documenta tion system of all blockages involving lines or ducts containing hot. corrosive or pressurized gases, fluids or solids that require a cleanout. CASE HISTORY NO. 1806 Laboratory Explosion Description: A scientist was injured when a vacuum strip ping flask exploded in his laboratory. The injured suffered severe lacerations of the underside of both upper arms, facial, thumb, and chest cuts, and a severed tendon in the little finger of his left hand. He also suffered thermal burns on arms, face and chest. In addition, there was possible irritation of the respiratory system. Morpholine disulphide in carbon tetrachloride had been treated with chlorine to produce morpholine sulfenyl chlo ride. Upon completion of vacuum stripping, the solvent from the reaction product, the 500 ml. filtration flask con- ing the product exploded in his left hand. le was given prompt and efficient first aid. This included inundation under a safety shower, and the application of compresses to the major wounds to restrict loss of blood. He was taken to the hospital by the local emergency squad. At the hospital, prolonged surgery was required to clean and close the wounds. The bums were treated and dressed. In addition, plasma and blood were administered to compen sate for the blood loss, and treatment for shock was required. Repair of the tendon was temporarily deferred. Safety glasses prevented injury to his eyes. Cause: No established safety practice was violated. The reaction was one thai had been carried out many times before in these laboratories, and is described in the literature. The explosion resulted from a chemical decomposition or rapid chemical reaction of materials in the flask, with vigorous gas evolution. The cause of the explosion was not definitely determined. Preventive Measures: 1. Since sulfur-nitrogen chemistry is the backbone of rubber chemicals, a better understanding of the chemistry involved in this accident is imperative. It is recommended that a carefully planned program of investigation be initiated immediately. This should include literature search, synthesis and preparative work, analytical studies, thermal analysis, and consul tation. 2. The safety program and established safety practices should be critically examined. Included should be first aid procedures and facilities, rescue operations, employee indoctrination, prompt issuance of a loca tion safety manual, work during off hours, and other related topics. CASE HISTORY NO. 1807 Flammable Gas In A Piston Void Description: A machinist was preparing a cast iron pump piston for metalizing. One step in this "routine" job is to drill a small vent hole into the piston void to prevent pressure build up during a baking step. This piston had been in steam service and there was no concern about a flammable gas being trapped in the void. However, as the drill bit penetrated the cast iron shell, a flame shot three feet from the hole and burned the machinist on the hand and stomach. The contained gas was analyzed and found to be almost 90 percent hydrogen. Cause: The hydrogen is surmised to have entered the sealed void by a process known as counter current atomic hydrogen diffusion which can occur whenever a ferrous metal rusts. The hydrogen atoms will move through the ferrous material from one atom of iron to the next until they surface in the void and combine with another hydrogen atom to form a hydrogen molecule. The atomic hydrogen can move from an area of low pressure into an area of high pressure such as the sealed void. In this case the hydrogen ignited upon being released. -67- CMA 048781 Preventive Measures: 1. Assume that all pistons to be treated contain flam mable gases. 2. An air drill with a water course will he used to drill the hole. 3. The work will be placed behind a barrier and the drill will be remotely operated in order to protect personnel against a possible fire or explosion. CASE HISTORY NO. 1808 Thionyl Chloride Incident Description: A chemical operator was recently injured when a flexible stainless steel hose carrying thionyl chloride rup tured from over-pressure. The operator received multiple contusions and abrasions plus a laceration of the left chest. Fortunately, none of these injuries was serious. At the time of the accident the operator was transferring thionyl chloride by vacuum from a 55-gallon drum through a 1-inch flexible, stainless steel hose and dip pipe device. Because the hose and dip pipe assembly was leaking, the operator substituted a second hose and dip pipe assembly. He saw nothing draining from the substitute hose, so he exchanged it for the hose of the initial assembly and inserted the dip pipe into the drum of thionyl chloride. When he opened the feed valve, the flexible hose ruptured and pulled the dip pipe out of the thionyl chloride drum. Either this dip pipe and/or portions of the flexible hose struck the operator on the chest. Cause: The rupturing of the inner section of the flexible line indicated it was due to a pressure build-up, not an explosion. There was no blackening on the pieces of the flexible hose, valve or inside of the reactor -- therefore, it is concluded there was no fire present. Equipment damage was relatively minor. A thorough investigation of this accident indicates the direct cause was contamination of the flexible transfer hose with water or caustic, which reacted with the thionyl chlo ride. Thionyl chloride reacts violently with water, liberating hydrogen chloride and sulphur dioxide, both gases: resulting in an expansion ratio of 3700:1. It is calculated that one teaspoon of water reacting with thionyl chloride would generate over 280 psig pressure in the transfer hose. Preventive Measures: 1. The existing manufacturing procedures for the opera tion indicated that thionyl chloride "reacts with water ..." To add more emphasis to this point, this pro cedure, and others using similar water reactive chemi cals. will be revised to state "reacts violently with water ..." 2. An approved procedure should be developed and placed in operation for the cleaning and drying of flexible hoses and dip pipes used in transferring all chemicals. CASE HISTORY NO. 1809 Hot Acid Burn Description: The employee was performing his routine dut\ of sampling a residue. The sampling was completed and as he was in the process of closing the sample valve, he accidentally bumped the quick-opening bleed valve with his elbow'. This discharged the residue directly on the anterior portion of his thighs, requiring hospitalization of employee. Cause. Quick-opening bleed valve located too close to sam ple valve Preventive Measure: Both the sample valve and bleed valve will be relocated. CASE HISTORY NO. 1810 Sulfuric Acid Splashes in Employee's Mouth Description: A journeyman pipefitter straddled an acid pit cover while jerking on a dip pipe embedded in sulfuric acid sludge. The sulfuric acid splashed onto his mouth, causing minor bums to his lip. Preventive Measures: 1. Employee reprimanded with verbal warning for not wearing protective clothing and equipment specified in line opening procedures. 2. Line opening procedures will be reviewed for neces sary improvements. CASE HISTORY NO. 1811 Broken Leg From Oil Spill Description: A production foreman suffered a fractured leg when he slipped on an oil spill. The foreman was preparing a railroad spur for switching when he noticed a steam heating hose laying across the railroad tracks. There had been a hard downpour of rain and some oil was washed out of the shelled area onto the street. In his haste to arrange the hose, the foreman did not notice the oil slick, since there was oil and water on the street. Cause: The shelled area at this location was approximately 2" to 3" higher than the street level and residual oil and rain water drained toward the street during the heavy rain. Preventive Measure: The shelled area has been lowered to a level that will allow the water to shed in a direction away from the street. -68- CMA. 048782 CASE HISTORY NO. 1812 |tr Hose Accident Description Two employees were in the process of return ing a high lift to its storage area, when they came upon an air hose laying across the roadway. The high lift operator asked the injured employee, who had only five weeks com pany service, to turn off the air and disconnect the hose. The injured proceeded to disconnect the air hose without shutting off the air. assuming that it was not under pressure. The air blast imbedded foreign bodies in his wrist. Cause: Because of the noise from the high lift, the injured employee did not clearly hear or understand the operator's instructions. Preventive Measure: This incident was discussed in depart mental safety meetings, stressing the importance of all employees clearly understanding how a job is to be per formed . was noted. They then put the pump in place and began to bolt it up. After working for 10-20 minutes, another rubber plug, apparently upstream of the block valve, gave way allowing hot water to flow uninterruptedly through the valve and suction piping, and splashed on them. Each of the craftsmen lost 7 days work due to the accident. Cause: Subsequent investigation revealed the valve had been malfunctioning, and when it was disassembled it was found to have been in the fully opened position rather than closed. Preventive Measure: Any time a malfunctioning valve is found it will be appropriately tagged until it has been repaired. When there is a possibility of personnel being sprayed with steam or hot water, it will be mandatory to wear a face shield, rubber boots, and slicker suit and rubber gloves. CASE HISTORY NO. 1815 Explosion In Dust Extraction Unit During Primer Filling Operations CASE HISTORY NO. 1813 Lock-out Incident ^Dee:scription: A maintenance man was assigned to add ham- m rs to a spray dryer Micro-pulverizer grinder. With the ^^rreea foreman, he locked out the grinder. They proceeded to the grinder room and tried the stop-start switch and the grinder started. Cause: Subsequent investigation revealed the circuit breaker handle broke oft inside the panel when the handle was placed in the off position to install the lock-out lock. Preventive Measure: This incident points out the necessity to try the stop-start switch even though the equipment is locked out. CASE HISTORY NO. 1814 Hot Water Burns Description: Two craftsmen were splashed by hot water while installing a slurry pump. They had assumed that a block valve in the suction piping to the pump was in its dosed position when they failed to see the valve's stem. Closer investigation would have revealed that this particular valve was of the non-indicator stem type. All other valves in the area, in similar service, were of the indicator stem jvpe. After making this assumption they proceeded to cau*usly remove a blind from the flange on the suction pipmg, At this time only a very minute amount of water came out of the pipe. Next they removed a rubber plug in the piping, which was between the suction flange and the block valve, with a long screwdriver. Again, very little water Description: During filling of Primers Electrical Model 52 an explosion occurred in portion of the dust extraction system. The operator supervising the primer filling line had re lieved the operator at the dust extraction/disc insertion station and noted that the air flow through the dust extraction nozzle was low and the dust extraction inefficient. The operator removed the dust extraction nozzle from its holder and flushed the extraction system with compressed air to clear any obstruction. As she was replacing the dust extraction nozzle in its holder, an explosion occurred in the dust extrac tion system. The operator received a minor injury to her left leg from impact of fragments of Nylex tubing fractured by the explosion and she and two other female employees also received back injuries when they fell backwards off their stools due to shock from the noise of the explosion. Cause: The Operational Safety Committee noted that the use of compressed air to clear obstructions in the dust extrac tion system was not covered in the Operating Instructions. It was also noted that the air supply to the extractor was not applied continuously and between the periods of appli cation of air the explosive dust in the system could settle and cause obstructions. The cause of the explosion could not be determined but the most probable cause was the accumulation of static elec tricity in the dust extraction system arising from the appli cation of compressed air igniting some of the explosive dust entrained in the system. Preventive Measures: The Operational Safety Committee recommends that, 1. The air supply to the extractor be continuously applied during filling operations to prevent settling out of explosive in the lines. 2. To reduce the amount of build-up of explosive dust if a malfunction occurs, the line from the dust extrac tion nozzle to the water wash bottle is to be the shortest practical length and free of sharp bends. Long horizontal sections are to be avoided. -69- CMA. 048783 3. The lines be checked regularly for explosive build-up resulting in reduced air flow. 4. To entrain any water droplets containing explosive earned over from the first wash bottle, dual wash bottles to be used, the first containing water and wetting agent and the second containing glass wool or similar fiber. 5 These bottles be mounted on the working table and shielded from the operator. 6. The water wash bottle and any lines showing explo sive dust on the walls be cleaned at least once daily. 7. The bottle containing glass wool or similar fiber be cleaned or replaced at least weekly. 8. The metal fittings to the bottles be replaced with plastic tubing and rubber stoppers. 9. The use of conductive tubing be investigated. 10. The interior of the extractor be checked weekly for any blockage which might reduce the air flow through the dust extraction nozzle. 11. The practice of blowing out lines with compressed air be discontinued. 12. The operation of cleaning discs and washers from beneath the turntable by the use of compressed air be included in the Operating Instructions. Department of Defense Explosives Safety Board Case His tory CASE HISTORY NO. 1816 Hand Caught in Weigh Hopper Description: An operator attempted to remove a piece of rubber that was stuck in the weigh hopper which was pre venting the chute door from closing. He set the controls in the manual position and as he pulled the rubber out, the door started closing, pinching his left hand across the palm, causing a severe contusion. Cause: The air cy Under which operates the door had a pres sure buildup trying to close on the piece of rubber that was blocking the door. When the piece of rubber was re moved the residual pressure closed the door on the operator's hand. Preventive Measure: 1. Install a bleed valve in the air supply line to bleed the air oft the cylinder when work is to be done on the unit. 2 Discuss this incident in detail at all safety meetings involving operators and maintenance personnel who work on this type of equipment. tivities. in non-conductive containers without inerting the container. The article follows: "A series of events that occurred recently in our pilot plant point out that special static-electricity problems can exist in vessels lined with nonconductive materials. In one instance, a 500-gallon batch of heptane saturated with a nonpolar, partially crystallized product, was being cooled in preparation for centrifuging. When the temperature reached about 25C, an explosion occurred within the vessel, followed by a second and a third at about 20-min. intervals. "All the explosions were safely vented outside the pilot plant building by a 4-inch rupture disk The pressure-relief system worked so well that it took three explosions before we finally found the source of the muffled sounds. Upon stopping agitation, the explosions also stopped. "The batch was allowed to settle under nitrogen for 12 hours while the material was checked chemically for any possible causes of the explosions. During this time, some calculations were made that indicated the vapor above the mixture had entered the explosive range at about 26C, and remained in this dangerous situation until the tempera ture went below -- 10C. "Although a nitrogen purge had been maintained on the vent, the purge meter used had a capacity measured in cc./min. of nitrogen. This was orders of magnitude smaller than needed for the cooling conditions, when the rapid decrease of the vapor pressure of the solvent in the vessel caused air to be sucked into the vent. "It was speculated that a break in the lining located just above the liquid level could act as an electrode to receive a static discharge from the liquid. This was found to be indeed the case, since after the vessel was thoroughly blan keted with nitrogen, and the agitator started, a 1'/; inch long spark could be seen. "The spark occurred with a frequency of about 2/sec., between the liquid and a spot just above the liquid level, about one-third of the way up the baffle. Adding a small amount of wetting agent to try to raise the conductivity of the liquid to a safe level only served to decrease the frequency of the sparking slightly. "Subsequent inspection of the vessel showed up several porous spots in the lower dish lining plus some pinholes both in the baffle and the agitator. "It can be concluded from this that if there is a chance of pinholes in a lined, agitated vessel, and jf the agitated liquid is of low conductivity (less than 1010 reciprocal ohm-cm.), and particularly if there are two phases present, then care should be taken to exclude air if the temperature range is to be such that the liquid's vapor pressure will produce an explosive mixture with air. This can be accom plished by closing the vent, and maintaining a slight positive inert-gas pressure on the vessel with a properly sized pressure regulator." CASE HISTORY NO. 1817 Explosions Caused by Static Electricity Static-electricity-caused explosions are described in an article in the December 27, 1971 Chemical Engineering. It was pointed out that this could explain some of our centri fuge explosions. Certainly we should not move non-polar solvents, such as hexane, which have high electrical resis CASE HISTORY NO. 1818 Employee Overcome During Tank Entry Description- A dryer technician was overcome by VCi as he was cleaning inside a "poly.'' The poly had been properly prepared with respect to isolation of piping, lock out requirements, ventilation, and a vessel entry permit was issued. Because the charge had set up and VCI pockets -70- CMA 048784 were present, the man was required to wear an airline j^pirator. The man, wearing the airline respirator, entered poly and within three minutes he was overcome. The standby noticed the man's condition and immediately notified building personnel for help. The man who was overcome was removed within 40 seconds and immediately revised. Cause: An investigation revealed that the demand flow reg ulator had been tampered with to make it a constant flow regulator. [Two large washers had been inserted on top of the diaphragm.) It is thought that the washers had moved out of place causing the needle valve to open partially. It was also noted that the diaphragm had two small holes. With this situation present it is possible that the VC1 entered the mask through the regulator casing. Preventive Measures: 1. Require checking the airline respirator and regulator prior to each use. 2. Use a constant flow regulator rather than a demand flow regulator. 3. Issue an airline respirator to each work shift. 4. Conduct safety meetings with personnel covering the incident and proper operation of the airline respirator. CASE HISTORY NO. 1819 Near Accident With 13,800 Volts A construction group, working off a suborder from a Field Department, were digging a trench and laying tele phone conduit between two buildings. The conduit was run ning 90 to the 13.800 volt cable, running to Bldg. "A". The elevation of the conduit was approximately the same as that of the cable. A back-hoe with an operator was leased from an outside contractor to dig the trench. The back-hoe severed the cable causing a shutdown of a portion of three buildings and lasting nearly an hour. The prime concern in this situation is that the operator of the back-hoe could have been electrocuted. Luckily, he escaped unharmed. Equipment can be isolated from electrical ground potential because of its tires. Upon severing a cable it would be possible to liven the machine electrically so that anyone touching the machine could receive a shock or even be electrocuted, or the operator upon dismounting from the machine could come in contact with the ground while still touching the machine and endure the same consequences as a person touching the machine. Signs indicating the location of the cables were positioned approximately 100' in each direction from the place the digging occurred. The sign that should normally be located near the spot was not there and could not be found. There is no reason to assume that at another time, a digger who is not familiar with the area will not do the same thing with possibly more serious results. Hence, every one in position to direct a digging operation should be aware #this temporary cable. 'retentive Measures: ). In the case of the telephone conduit -- all work was stopped. The Engineering Division was contacted and requested to provide accurate information as to where the conduit should be located. 2. New poles with signs indicating the presence of the high voltage cable will be installed along the building construction site. These poles will be located closer together and facing in different directions to be legible from different locations. 3. A meeting of parties most concerned with this type of w'ork has been held to assure that no future digging will proceed without proper drawings and proper clearances. CASE HISTORY NO. 1820 Line Cleaning Description: A group of employees along with a Factory Representative were working at checking and cleaning out the propane vaporizing and the propane-air blending sys tems. One of the problems being worked on was the accumu lation of slag, dirt, and trash in the lines, valves, automatic controls and blender. The debris had been introduced via the air line to the blender prior to the installation of a filter in that particular line. The top of the blender was removed and the men were cleaning out the air line by blowing it out with air from the propane air compressor through the open blender. The propane vapor line to the blender was also in need of cleaning by some means. The decision was made to blow it out with vaporized propane from the unit. The vaporizer system which utilizes a gas-fired burner had been running for some time prior to this. The hazard inherent in this operation was recognized by the men and they cleared the building which houses the blending system prior to blowing out the line. After the building had been cleared, the Factory Representative opened a manual valve in the propane vapor line on the southend of the vaporizer and allowed propane vapor at about 70 psig to blow through the line and out the open blender for a short period of time (estimate varies from one to three minutes). He then shut the valve and went to the northend of the vaporizer to adjust the thermostat on the burner to desired temperature range (the burner was still operational and is located at the northend of the unit). He had just backed off from adjusting the thermostat when the men saw the fire flare up at the burner and streak down to the blender shed. One said he could see propane vapors along the ground from the shed to the burner area. The flash fire blew out the burner and the propane vapors burned out rather fast, but ignited cleaning rags around the blender and set the grass west of the blender-vaporizer area on fire. In the opinion of the committee, the fire was a result of an unsafe procedure. The act of blowing the trash out of the propane line through the open blender by utilizing vaporized propane allowed a significant amount of propane vapors to escape to the atmosphere and travel to the lighted burner approximately 35 feet away where they were ignited. Cause: Unsafe procedure. Preventive Measures: 1. In the future, any blow-out of the lines and equipment -71 - CMk 048785 for cleanout purposes should be accomplished with CO2 or some other inert gas. 2. It should be a rule, supported and highlighted by appropriate signs in the area, that the blender and pipelines containing propane will not be opened while the vaporizer burner is lit and the pilot activated. All pipelines are to be labelled as to their contents. 3. Install another fire hydrant in closer proximity to the vaporizer-blender area, either west or southwest of the area. 4. Any propane leaks discovered should be repaired immediately to prevent or minimize vapor emissions. 5. The Committee concurs with Maintenance plans to ventilate the blender building to prevent propane vapor accumulation. CASE HISTORY NO. 1821 Communications Description: A fork truck operator was using a fork truck to unload a trailer at a loading dock at Building 605. A tractor driver spotted a trailer at the next loading dock and asked which trailer was ready to be moved. The reply was, "The one at the next door." There were a couple of "next doors," one on either side of the fork truck operator. The tractor driver dis connected his tractor and hitched it to one of the next trailers, removed the wheel chock and looked inside. He stated that he saw only three or four pallets of material but thought it was a partial load going back to Building 205. He started to move and heard a crash. He stopped imme diately and came to the back of the trailer to find a fork truck, minus the driver, hanging between the loading dock and the trailer. Fortunately there was no injury to the driver. Preventive Measures: The recommended safe practice for the movement of trailers away from our loading docks is being reviewed with our tractor drivers. Since material is stored and shipped from both Buildings 205 and 605, we have a shuttle service between the two buildings. We are moving partial loads both ways depending on the need. We also have three rented trailers on this cycle with swing-open rear doors. (All our own trailers have the roll-up garage-type rear doors.) For years, standard safe practice for our tractor drivers has been to check and be sure the rear door is closed before moving the trailer out. To minimize the danger when a trailer with swing-out type rear doors is being moved out, a chain with a sign hanging on it is to be placed across the building door opening by the platform checker. The sign on the loading dockside reads "O.K. to Move" which indicates to the tractor driver that the trailer is ready to go. The chain was not in place when this accident happened. The responsibility for placing or removing this chain has been reviewed with all the platform checkers in the area. CASE HISTORY NO. 1822 Static Electricity Methanol-water mixtures can be ignited by static. A fire occurred in a 500cc polyethylene bottle as an operator was taking a sample of 40 percent methanol and 60 percent water. The temperature was 30C. (86F). Subsequent test approximating conditions when the sample ignited showed static charges up to 1,000 volts were generated. Containers should always be held against the sampling tap and the contact continued while the sample is being taken. CASE HISTORY NO. 1823 Computer Facility Humidity Damage Averted By Fire Smoke Detector Alarm A fire alarm was received from a computer facility. Re sponding personnel noted high humidity and some odor of smoke. Investigation revealed the facility air-conditioning system was malfunctioning due to burnout of a solenoid which left the water control valve, for the humidifier, in an open position. It was smoke from the overheated solenoid that caused actuation of the fire smoke detection system which, in turn, sounded the alarm, instigating prompt correc tion of the problem before significant high humidity damage had been suffered. The above incident, in part, attests to the benefits from fire smoke detector system use on computer facilities. It also suggests need for recognizing and evaluating the poten tials for property damage in the event of failure in air-condi tioning system humidity controls, U.S. Atomic Energy Commission Case History -72- 048786 'V CASE HISTORY NO. 1824 ipetting A chemist became nauseated and ill when he used a pipette contaminated with amyl nitrite to suck up a dilute citric acid solution. He believed the pipette was clean because he obtained it from the drawer which normally has only clean glassware. This is another injury' to add to the long list of accidents caused by' mouth pipetting. As this case clearly demonstrates, pipetting by mouth can be dangerous even when working with non hazardous sub stances such as dilute citric acid solutions. Cause: Investigation revealed that when this particular tower was stopped, by dropping the dip tank, it would coast for 23 seconds; the same procedure on the other towers stopped them in 5 seconds. Due to this deviation, the regular operators of this machine used the emergency stop switch which halted the machine in 5 seconds. The substitute operator was not aware of this procedure, therefore, he stopped the machine by dropping the dip tank. Preventive Measure- The dtp tank switch has been con nected to the emergency stop switch which now halts the tower in 5 seconds. CASE HISTORY NO. 1825 CASE HISTORY NO. 1828 A Power House serviceman was injured in the right eye when an air hose struck him. He was preparing to dry a fuel oil strainer he had just washed, grasped an air hose about a foot from the end and cracked open the valve. The hose w hipped under his safety spectacles and struck his eye. The air pressure had not been reduced to 30 psig as required prior to the injury. CASE HISTORY NO. 1826 ne Repair A pipefitter received a foreign body in his eye while disconnecting a frozen overhead caustic line. Flange bolts were loosened and he used a hammer to force the bolts out of the flange. While doing so he felt a piece of rust enter his eye. but feeling no discomfort he continued. That evening he felt discomfort and had to have the foreign body removed, Eye protection should have been worn before he started to work on this caustic line. CASE HISTORY NO. 1827 Variation in Machine Characteristics Description. Employee was preparing to start up a film coating tower. To accomplish this, the cellophane is gathered together as a rope, threaded through a dip tank and up through a pair of doctor rolls. Immediately prior to the accident, the tower was running without film in order to clean the doctor rolls. The regular operator was having lunch and an operator from the adjacent tower was preparing the machine for film coating. It is routine to drop the dip tank to stop the tower by means of the dip tank switch or relay, instead of using the stop, or emergency stop switch. The employee dropped the dip tank and immediately grasped the film in his left hand. He started to push the film through the underside nip of the doctor rolls, however, the roll had w stopped turning and his left hand finger tips were pulled Ko the nip. Injury Lacerations and contusions to finger tips of left hand. Hand Exposure from X-Ray Diffraction Unit Description: In order to insure proper alignment of the goni ometer which had been moved to a different beam port the day preceding the occurrence, the scientist involved was running standard silica samples according to the operat ing manual. He turned the X-ray unit on during the morning and worked on the alignment procedure until lunch, leaving the X-ray unit "on," Following lunch, he was involved in some other work so he was unable to start work on the alignment procedure until later in the afternoon. He went behind the machine, propped open the port with a piece of lead, and spent approximately fifteen minutes per forming various measurements. When he returned to the front of the unit he noticed X-rays were being counted by the proportional counter and realized the machine had been on when he was behind the unit. Dosimetry Evaluation- Because of the variable nature of the operations performed, it was not possible to determine accurately the times of exposure and exact locations of sur faces in the X-ray beam. Skin dose to a portion of the left hand could have been as much as a factor of 20 higher or a factor of 2 lower than that shown, and the dose to the skin of the upper arm and right eye could have been a factor of 2 higher or lower; however, the lack of clinical signs on skin surfaces other than the left hand, as of this date, indicates a probable dose to the upper arm of less than 1500 rem. Due to the low energy of the X-rays and the limited area exposed, the dose to the blood-forming organs and gonads was less than 100 mrem. Preventive Measures: 1. Greater emphasis must be placed on the hazards associated with X-ray generating equipment. 2. Warning devices should be installed on X-ray equip ment which are recognized from any approach and which should be made failsafe if possible. 3. Appropriate signs should be posted on equipment when X-ray generating equipment is operating. 4. Training courses for operators of equipment should include biological aspects of radiation damage as well as operational aspects. 5. X-ray generating equipment should not be left un attended with the X-ray tube activated, unless doors to the room are locked. -73- CMA. 048787 6. All beam ports which are not used should be secured in the closed position in such a manner which will prevent casual opening. U.S. Atomic Energy Commission Case History' CASE HISTORY NO. 1829 Electrician's Fish Tape Description: Electricians had installed a 3-inch conduit to an existing electrical substation. Bare bus bars at 440 volts were about two feet from the end of the conduit. To install wires in the conduit, electricians pushed a steel fish tape through the conduit from the outer end. When the fish tape came through the conduit, it struck the bus bars resulting in a violent electrical flash. Fortunately, no one was nearby and there was relatively little damage to equipment. Similar incidents have occurred involving 2300 volt cir cuits with, of course, more serious damage. Preventive Measures: Barriers should be set up so there will be no chance of a fish tape striking a bus bar or other exposed electrical equipment. Such jobs should be carefully planned, and fish tapes or wires marked to indicate when the end of the conduit wall be approached. A man should also be stationed in the substation where he can observe but not close enough to be in danger. The possibility of using a non-metallic fish tape should also be investigated. CASE HISTORY NO. 1830 Clamp Truck Injury An operator of a ' `high-lift-walkie-truck" was moving a 24-inch diameter film box toward a materials handling station. In doing so he was walking backwards. Another operator of a "three-high-damp-truck" was driving forward toward him. However, his attention was diverted by a third person standing at an IBM station and he struck the "high-lift-walkie-truck" operator on the hip with the drum clamps. This accident could have been averted: a) if the walkie truck operator had been facing the direc tion in which he was walking. b) if the clamp truck operator had been keeping his mind on his job. or by stopping when distracted. c) if the damp truck operator had been driving the clamp truck in reverse so the mechanism would not obstruct his view, and. d) if there were less congestion in the work area. CASE HISTORY NO. 1831 Aluminum Ladder Three workmen have recently recovered from poisoning by one of the deadliest gases known, after a team of thirty Temple University Hospital doctors, nurses, and technicians struggled with the ailment for six weeks. They had been working in a tank at a chemical plant when they became victims of a freak combination of circum stances and chemical mixtures. They happened to be using an aluminum ladder, instead of the usual wooden one. to go into a tank containing sodium hydroxide, arsenic tnoxide and sodium arsenate. The aluminum reacted wath one of the chemicals in the tank and released hydrogen which combined with other chemi cals. The result was arsine. The three men were in the intensive care unit of the hospital for nearly a month and their treatment included two complete changes of blood for each man. CASE HISTORY NO. 1832 Lithium Aluminum Hydride A reaction involving lithium aluminum hydride in ether had just been completed and the heating mantle was being replaced by a cooling bath. The flask held by two clamps dropped several inches and hit the jack which was used to support the heating mantle. It cracked, allowing ether and hydride to spill on the bench. When the ether ev aporated, the hydride ignited. CASE HISTORY NO. 1833 Mechanical Equipment Description: During the night shift when the Production assistant foreman was finalizing a mold set-up in an injection molding machine, he realized that the press was not opera ting . At this time the shift foreman arrived and after knowing what the problem was, proceeded to manipulate the push buttons while the assistant foreman was revising the position ing of the various microswitches that interlock the press. When the assistant foreman manually operated a micro switch, the press was released and started to close since the foreman was still actuating the push button. Together with the press displacement, the cam system that operates the microswitch, so moved forward, caught and removed the distal phalanx of the assistant foreman's left medium finger. Cause: 1. Incorrect operating procedure; because two people were working on the same machine with both assum ing leadership. 2. The assistant foreman actuated the microswitch by hand, which is an incorrect operation, and he knew that. 3. Incorrect communications between foreman and his assistant. Preventive Measures: 1. Reinstruction of all Production Supervisors that any adjustment on a machine should be made by only one person. 2. Review with all Production Supervisors operating methods for adjusting injection machines. - 74- CMk 048788 CASE HISTORY NO. 1834 'Trifluoromethylphenylmagnesium Bromide and Trifluoromethylphenyl Lithium An article by I C. Appleby of Pfizer Limited in Chemistry and Industry, Jan. 23. 1971, p. 120, described the potential hazards involved in the preparation of m-trifluoromethylpheny(magnesium bromide. He describes an explosion which occurred under the following conditions; "mBromotrifluoromethylbenzene (2 kg) was added to magne sium turnings (273 g) in sodium dried ether (5.67 1) at such a rate as to maintain gentle reflux. The ether contained no peroxides and the m-bromotrifluoromethylbenzene con tained 2.59! m-chlorotrifluoromethylbenzene as the only impurity. The reaction had been previously initiated by the addition of 1 ml of ethyl bromide and was being conducted under a blanket of dry nitrogen. After approximately 1300 g of m-bromotrifluoromethylbenzene had been added, white fumes were observed in the reaction vessel and a violent detonation immediately followed which resulted in extensive damage to two fume cupboards but fortunately no serious injury to personnel." An earlier unpublished report about the same compound has since been brought to our attention which states: "in a 5-mole run on one occasion, after stirring for about a half hour after complete reaction with magnesium, the con tents blew up," We are also aware of a violent explosion occurring in a third laboratory while preparing research antities of o-trifluoromethylphenylmagnesium bromide der conditions similar to Appleby. Exotherm studies involving m-trifluoromethylphenylmagnesium bromide prepared in dry ether show a violent decomposition at about 75C. When the Grignard was pre pared in benzene-tetrahydrofuran, a less violent decompo sition was observed at about 90C. No consistance factor is available, however. Concerning the mctalation of o-bromobenzotrifluoride using n-butyllithium, one worker reports: "I was successful the first time. In a repeat run, after metalation and proceeded and refluxing in ether had been continued a few hours, the apparatus blew up, violently. This was preceded by an orange ball of fire in the interior of the flask, under nitrogen." We have not experienced the above problems in the prepa ration of small quantities (less than one mole) of m-trifluoromethylphenylmagnesium bromide by keeping the reaction temperature below 40C during addition of m-bromobenzotrifluoride to the magnesium. However, we are not certain this will completely prevent difficulties and urge you to take all safety precautions. This information is presented so that you are aware of a potentially dangerous situation which has heretofore been overlooked. CASE HISTORY NO. 1835 Tank Car Unloading tank car pumpman received a cut leg requiring sutures while trying to escape from acid fumes. His leg became sore the following day and he had to stay home. The man was disconnecting the unloading hose from a chlorosulfonic acid tank car when it got caught on the tank farm railing. He walked onto the tank car and pulled it loose. Residual acid in the hose contacted water on the ground and fumes rose up to where he was standing. He was forced to leave and tried to ease himself down to the small catwalk on the front of the car. He slipped and fell to the ground, hitting his leg on the car coupling. The plant is studying methods for better drainage of the hose. CASE HISTORY NO. 1836 Transfer Pipe Causes Chemical Splash A chemical operator suffered chemical bums of his right eye, neck and face while transferring acidic liquors. A 4-5 foot length of rigid PVC pipe inserted into a length of Tygon tubing is used to transfer this layer from one vessel to another via the manhole. The two sections parted and he was splashed. He did not remember being splashed in his eye, but he may have gotten some into his eye while washing his face. CASE HISTORY NO. 1837 Centrifuge Explosion The following report of a centrifuge explosion demon strates the importance of automatic emergency nitrogen for inerted centrifuges. At about 2:00 A.M., flames were seen coming from the outside back of a Penton-lined centrifuge. An instant later, an explosion blew out the sight glass and blew open the access door on the top of the centrifuge. Flames erupted through the open lid and around the outside of the centrifuge. Within 5-10 seconds, the flames had been extinguished by two operators armed with dry chemical fire extinguishers. No personnel were injured, although the operator attend ing the centrifuge was blown back against the panel board. The man-way top of the centrifuge will have to be replaced. Three glass pipes were broken and about 10% of the trans lucent, green blowout panels in the building were blown out. Examination of the equipment after the explosion indi cates that the incident started outside the centrifuge. The drive belts were rubbing against a copper grease tube, and the friction heat caused by this apparently ignited a methanolair mixture spilled outside the centrifuge. The flame burned a hole in a rubber boot just under the centrifuge and allowed air and flames to enter the basket, presumably causing the explosion. Although the centrifuge was blanketed with nitro gen per procedure, it lacked capacity to overcome the hole in the boot. CASE HISTORY NO. 1838 Throat Laceration Caused by Portable Grinder Description: A welder was using a portable electric grinder when the rotating wheel struck a vise, causing the grinder to bounce and strike his chest and neck, resulting in a deep throat laceration. He received treatment at the plant's medi cal facility and then was transferred to a hospital where CMA 048789 1 twenty-four stitches were required to close the wound. He returned to work the following day. It has been observed during recent field visits that there is a general need for review of compliance with the ANSI Standard B7.1. "Safety Code for the Use, Care, and Pro tection of Abrasive Wheels." Particular attention should be given to proper guarding, to the provision and use of the proper si7t flanges and safety' washers, to identification of wheel speed ratings and assuring that wheels are not used on tools or machines running at higher speeds, and to proper care of wheels to prevent their being damaged. AH portable abrasive grinding tools should be equipped with "Dead Man" switches or controls and other safety provisions, as outlined in the B7.1 standard. U.S. Atomic Energy Commission Case History CASE HISTORY NO. 1839 Mixer Hand Twist Description: A technician received a severely strained right hand while attempting to clean the shaft of a 1/3-hp Lightnin Mixer. With rubber gloves on and the mixer running, he proceeded to clean the mixer shaft with a metal sponge. The right hand glove caught on the shaft causing his hand and arm to be pulled around the shaft. While calling for assistance, he grasped the mixer shaft with his left hand and managed to stall the mixer, but could not get loose. Luckily, a co-worker in an adjacent room responded to the call and turned off the wall switch within 20 to 30 seconds. Motor overload protection had not reacted within the short time interval. Preventive Measures: 1. Person should not work around equipment in motion while wearing gloves. 2. Standard safe practices for cleaning shafts should be followed. A touch of irony may be added by noting that this same person, only 13 days before, had cut himself while washing beakers. He stated at that time, the accident could have been prevented by wearing gloves. CASE HISTORY NO. 1840 Compressed Gas Errors Two compressed gas errors were reported recently which could have had serious consequences. (a) A tube trailer labeled "Oxygen" was used to deliver nitrogen for a purging operation. Although the cargo was actually identified as nitrogen, the serious conse quences of an error in identification were obvious. All such trailers are now being checked for oxygen content before being admitted to the plant. While experience shows that gas cylinders can be improperly marked, it is the human error of failing to identify that must be guarded against. Read the name on the label. If the fitting is different from normal, recheck all identifying markings. While color code cannot be relied upon, a differ ence could be the clue to a mistake. Check before using. In case of doubt, return unopened to the vendor. (b) An employee collapsed while wearing an air mask supplied with air from a cylinder. He u'as promptly revived. Investigation revealed that although the cylinder of air was tagged by the plant as having been checked for oxygen, the oxygen content was less than 1 7c. To provide breathing air, the supplier had mixed nitrogen and oxygen in cylinders, but failed to add oxygen in this case. The plant's procedure for check ing such cylinders involved placing "OK" tags on them, after all in a shipment were checked. It is probable that this particular cylinder was missed while the analysis was being made. All other cylin ders were checked and found to be OK. To prevent recurrence, vendors supplying breath ing air cylinders to the plant were requested to perform more reliable checks at their filling locations and to supply only compressed air and not a mixture of nitrogen and oxygen. Procedures were also estab lished to insure that all incoming cylinders of breath ing air would be reliably checked by plant per sonnel. Users of breathing air were instructed to take breaths from a mask, for a minute or two, before strapping it on, whenever feasible to do so. In this case the employee returned to work without any adverse effects. CASE HISTORY NO. 1841 Materials Handling Description: Two mechanics were moving a 7 foot high, 25 cubic foot refrigerator, weighing approximately 500 lbs. The refrigerator has a high center of gravity due to the condensing unit being located at the top. Two manuallyoperated hydraulic hand trucks (standard refrigerator dollies) not equipped with braking devices or wheel locks were being used to hold the refrigerator approximately two inches off the floor, so that the legs could be removed. As the mechanics prepared to remove these legs, one of the hy draulic trucks rolled sideways a few inches and one wheel entered a floor drain depression. The top-heavy refrigerator tipped over sideways and fell to the floor, striking one of the mechanics and knocking him against the counter. The employee sustained a fractured shoulder. He was fortunate that his injuries were not more serious from this sudden crushing weight. Cause: This accident was caused when the normal procedure was not followed. Preventive Measures: Normally 2" x 4" wood blocking is used for cribbing or supports under a refrigerator while removing the legs. In this instance a decision was made to "take a short cut." All employees have been informed of this accident and instructed to follow the safe procedure -76- CMA. 048790 CASE HISTORY NO. 1842 CASE HISTORY NO. 1844 Potassium Permanganate Ignition Leak in Tankcar Gauging Well Potassium Permanganate, being conveyed on a test basis through a modified screw type conveyor called a `TransaTube', caught fire in the end of the tube whre it connected to the charge hopper The hard polypropylene tube burned for 60 minutes despite copious applications of water. Subse quent laboratory friction tests, even with a likely contain ment, did not cause any ignition of a piece of the conveyor tube. Three men cut their hands as they moved the drum of permanganate away from the fire. Their injuries were not serious. Description: Wearing prescribed personal protective equip ment (chemical goggles, rubber gloves), employee had spotted empty tankcar and connected loading and vent hoses. As he unscrewed gauging-well cap to activate gauging rod preparatory to start loading, liquid monomethylamine (MMA) sprayed onto his left arm, shoulder, face and neck. His goggles undoubtedly prevented eye injuries. The gaug ing device (Midland magnetic level indicator) consists of 6' x lVi" diameter well with magnetized "doughnut" float riding at liquid level on outside of well; it has a gauging rod with magnet on end inside the well; the inside rod follows the float and rises with liquid level in tank car. Amine vapor pressure in car, both loaded and empty, is about 40 psi. CASE HISTORY NO. 1843 Vacuum-Tank Truck Description: A vacuum was pulled on a tank truck while being unloaded. As on previous occasions, the tank col lapsed almost completely, although it did not rupture, nor were the contents spilled. Cause. Cause of this incident was failure to properly vent e tank. Tank trucks are usually not constructed, or procted to withstand even the slightest amount of vacuum and must be vented in a safe, adequate manner while being unloaded, Preventive Measures: To eliminate a potentially dangerous hazard to personnel and facilities, the following must be given immediate consideration and attention: 1. Review all sites where tank truck unloading/product transfer is being done for safe adequate handling. 2. Review this incident with all involved personnel plac ing emphasis on written operating instructions and physical characteristics of tank trucks. 3. VERIFY that the truck is properly vented before start ing the pump. Cause: Pinhole leak in the well permitted seepage of liquid MMA into well when car was previously loaded. Preventive Measures: Provisions for testing wells for pres ence of product are being made; design and installation procedures to prevent or minimize leaks in wells are being investigated; and reemphasis is being given to importance of promptly removing contaminated clothing, and immediate and thorough showering. CASE HISTORY NO. 1845 Mechanical Equipment Description: A utility man in the Polyflex Department caught his left hand and arm in the double belt feeder on the 20 x 50 Cumberland grinder. As he was placing Polyflex scrap on the take up conveyor, the grinder jammed. He then proceeded into the enclosed grinding room and removed the plexiglas guard covering the internal belts of the grinder. The micro switch on the guard was inoperative and the grinder and belts continued to run. As he reached into the machine to remove the jammed material his left hand and arm were pulled in between the belt and the roller on the conveyor belt. He then reached with his right hand to free his left arm and this hand was also pulled in between the roller and the belt. He was unable to free himself from the belt. Another employee found him about five to ten minutes later when he failed to take his scheduled break. The grinder was then shut off and the conveyor belt cut to relieve the tension so the injured employee's arms could be removed from between the roller and the belt. Cause: 1. Violation of safety rule by not shutting off grinder before cleaning. 2. Micro switch was inoperative because the wires had been disconnected at the junction box. Preventive Measures: 1. Replace plexiglas guard with a more durable expanded metal guard with two micro switches. 2. Establish written instructions and include a look-out procedure for unjamming and cleaning the grinder. -77- CM& 048791 CASE HISTORY NO. 1846 Ammonia Compressor Description: Tw o employees were injured when equipment failure released liquid ammonia to the work area. The men were preparing to charge a Vilter Refrigeration Compressor with ammonia. They had moved the ammonia cylinders into position in preparation for hooking them up for the charging operation. There are two valves that can be used for charging the compressor. The handle of the valve nor mally used tor charging was rusted off and could not be opened so the men proceeded to use the alternate valve. This valve discharges to the east. One prepared to remove the pipe plug from a position south of the valve, the other moved to a position east and slightly north of the valve to watch removal of the plug. As a pipe wrench was placed on the plug, the nipple on the pressure side of the valve failed, apparently from the weight of the wrench, and liquid ammonia was discharged into the area. The probable initial discharge of the ammonia was vertical and as the break (probably on top of the nipple) opened the angle of discharge went from vertical to horizontal and sprayed one of the men's face and clothing. Apparently, the other man was only sprayed on his hands, which were protected with gloves. As the ammonia was discharged it vaporized, filling the area with dense white fumes, forcing the men to fed their way along their escape routes. uuse: Inadequate maintenance. f The equipment failed due to severe exterior corrosion of the pipe nipple on the pressure side of the charging valve. The nipple in question was so corroded that less than 0,025 inches of the original pipe thickness of 0.147 inches was remaining. Although the remaining thickness of pipe was sufficient to retain the internal pressure of about 30 psi, the additional bending stresses caused by the weight of the pipe wrench and some possible impact caused the nipple to fail. In the opinion of the committee, the following factors contributed to the nipple failure and injury: 1. The vendor's operating instructions clearly suggest that all rust should be removed from the equipment and that it be cleaned and painted yearly. The commit tee does not believe that this has been done for several years. 2. There is evidence that insulation has been removed from the piping in the area of the failure. The commit tee believes that insulation would prevent frosting of the lines and help to prevent exterior corrosion of the piping. 3. One man's injury may have been less severe if he had taken a safer position to the side of the valve rather than almost directly in front of the discharge end of the valve. Preventive Measures: 1. Clean all rust from the Vilter Compressors. Inspect, repair, and replace as required all corroded piping, valves, flanges, etc. 2. Reinsulate all lines on Vilter Compressors from which the insulation has been removed. CASE HISTORY NO. 1847 Caustic -- Tank Car Valve Description: An operator sustained a caustic burn of his right eye while attempting to dose the valve on bottom outlet of tank car. The injured went out to the caustic unloading dock to begin unloading a caustic car to the storage tank. After preparation of the car and lines for unloading, he attempted to open the bottom outlet valve on the car and found he couldn't move it. He turned the large nut on the opposite side of the valve from the valve operator and hit it with a length of pipe to loosen the valve. He then opened the valve, hit it in place again, started the car unloading, and left the site. Shortly after noon, he returned to the car to prepare it for switching. When he tried to close the bottom outlet valve, he again found that he couldn't budge it. From a sitting position on the southeast side of the valve, he hit the valve, which was northwest of him and above his head, with a length of pipe. The valve was leaking around the plug. The blow caused caustic to splash behind his safety glasses into his right eye. With the help of the other operator who had been on top of the car, he got to the nearby safety shower-eye bath and began washing his eye. An Instrument Electrician came out of the electric shop about that time and assisted him to the dispensary and further irrigated the injured eye with water. Cause: The injury was the result of an unsafe procedure. Specifically, hitting the valve in the manner described above, without wearing adequate eye protective equipment con stitutes an undue risk. This incident points out again the necessity of wearing adequate protective gear when dealing with hazardous chemicals. Handling of the injury after the fact was good as evidenced by the copious washing of the eye at the safety shower, in the dispensary, and on the way to the hospital by the department foreman. During the course of the investigation, it was pointed out that these caustic cars sometimes come into the plant without the bottom valve (these cars have an internal valve operated from the top of the car in addition to the bottom valve). Lack of the bottom valve could cause problems if the internal valve should leak. Also, there doesn't appear to be a standard valve used as cars have come in with different types. Preventive Measures: 1. Always wear face shields and goggles when working around the caustic cars or any time the possibility exists of coming in contact with caustic. 2. All departments to review handling of hazardous chemicals in their respective departments at the next department safety meeting with particular emphasis on protective equipment and first aid procedures when contacted by hazardous chemicals. 3. Investigate the problems of missing or non-standard valves on railroad cars and attempt to work out solu tion with suppliers. --78 -- CMA. 048792 CASE HISTORY NO. 1848 park Ignition from "Explosion-Proof' Junction Box Description: A minor fire occurred when a flammable sol vent leaking from a valve was ignited by a spark from an explosion-proof junction box. Investigation showed that the ]unction box had corroded through and a wire was exposed which had shorted and sparked. This minor occur rence presents an excellent example of how the highly un likely circumstances of having an "open'' junction box, a bare wire, an explosive concentration and a spark -- all at the same time -- can happen. Preventive Measures: Either flushing down the spill as soon as it occurred, reporting the corroded junction box. or inspec tion as part of a preventive maintenance program, could have avoided this fire. CASE HISTORY NO. 1849 Acetylene Generation Description: Seventy-five grams of barium carbonate were reacted with 75 grams of magnesium metal to obtain barium carbide. When water was added to release acetylene, ex cessive heat was generated and the glass lid of the laboratory reactor blew off. On contact with air the gas ignited. An xtinguisher contained and extinguished the fire. reventive Measures: Prolonged cooling of the vessel is necessary when liberating acetylene and this was not done. In the future, all such reactions will be performed in a fume hood. CASE HISTORY NO. 1850 before removing the valve. Before the job was started, the maintenance supervisor checked with the production super visor as to the hazards associated with the contents of the tank. He ascertained that the chemical makeup of the slurry was not a concern because "you can wash your hands in it." The tank was checked after three hours to determine if the slurry had solidified from the dry ice packing. It had not, but the foreman and mechanics decided to go ahead with the valve change. This decision was based on the fact that two successful valve changes of this nature were completed in the past. The job was lined up with a fork truck, safety pallet, two mechanics and a fork truck driver. The fork truck was covered with a plastic tarpaulin to prevent the driver from becoming wet in case of a spill. The foreman told the mechanics to get rain gear, face shields and safety glasses for wear while performing the valve change. The injured employee stated that "the rain gear suit was hot and he didn't really need it." The foreman did not hear this remark and left for another job. Approximately ten minutes later the foreman returned and saw the mechanic on the safety pallet making the valve change. One of the mechanics had the protective equipment on while the injured employee was wearing glasses and face shield, but not the rain gear. The foreman asked, "Where is your rain gear?" and the employee replied, "If I get wet. I'll take a shower." At that time the bolts broke loose, the old valve fell and slurry was streaming out of the tank. The mechanics immediately attempted to place the new valve in position when the slurry covered both of them. The injured employee did not immediately shower, but continued to work on the valve for approximately fifteen minutes. He then felt the slurry burning him so he went to the locker room, showered, and was taken to the hospital for outpatient treatment of the 1st degree bums of the chest, waist, hips, upper and lower legs. Compressed Air Used for Cleaning Description. The use of compressed air for cleaning can be dangerous. A mechanic with a small cut on his finger washed some machine parts in cleaning solvent. Then, hold ing the parts in his hand, he dried them by blowing compres sed air over them. Shortly afterward he complained that his body and head felt as if they were going to explode. At the hospital his ailment was diagnosed as air bubbles in his bloodstream, caused by the compressed air striking the small wound on his finger and entering his bloodstream. He recovered, but he could have died. CASE HISTORY NO. 1851 iI | Lime Burns -- Changing Valve Causes: There were four main causes which contributed to the accident and the severity of the injury: a) The primary cause of the accident was failure to drain the tank before attempting to change the valve. b) Another contributory cause to the accident was failure to wear prescribed protective equipment by the injured employee. c) A further cause was the understanding of the mechanics and supervisory force that the material involved was not felt to be hazardous. d) A fourth factor was the fact that the injured employee did notimmediately go to a safety shower when he became wet with the material, but continued to work until a burning sensation was evident. Description: Two employees were changing a drop line gnged valve on the Dorr solids tank. The tank contained slurry mixture of lime and DCP. The approximate mperature of this mixture was 30C and pH of approxi mately 11.0. The tank was filled to capacity when the valve change was attempted. The conical section of the tank was packed with dry ice in an attempt to solidify the mixture Preventive Measures: 1. Establish maintenance procedures that will insure draining of material from the tanks to a level u. hich will be below the working level of employees. 2. Inform all plant personnel of the accident, the causes which contributed to the accident and emphasize the importance of wearing prescribed safety equipment. --79-- CMA. 048793 CASE HISTORY NO, 1852 Chemical Burns to Both Eyes Description An employee was filling a two gallon polyethylene jug with 32% HC1 from a 3'' pipeline by using a plastic hose connected to a 1" valve. The acid was being obtained for use to unplug a drain. The employee walked across the pipelines to get to the valve. Apparently the jug overfilled and splashed out. In his haste to get out of the way of the splashing acid, the man fell, striking his head on a pipeline and knocking his goggles and hard hat off. He then drove to an eye wash station a block away. He sustained chemical bums to both eyes. Cause: 1. Employee assumed an unsafe position by walking on the pipeline to get to the valve and by not placing the jug in a remote location from the valve. (Though safer access to the valve was available from another direction, the temptation to walk directly across the pipeway to get to the valve was cause enough to list the location as unsafe.) 2. Inadequate procedure and facilities for obtaining acid. This was not a routine job or facility. (The facility was installed as a temporary means to obtain acid several times a year.) 3. No eye wash facilities in the area. Preventive Measures: 1. Discontinue the practice of obtaining acid from pipe lines and stop using acid for cleaning equipment until the following is done: a) Resurvey uses of acid for cleaning media and determine if the use should be continued. b) If it is determined that acid use should continue, then adequate means and procedures for obtaining and using acid will be established. 2. Provide portable eye wash bottles in department vehi cles . 3. Review the hazards of walking on pipelines with all employees. machine was not grounded and that the actual ground wire to the disconnect switch had been cut off. CASE HISTORY NO. 1854 Fume Exposure Description: Through an operating error (plug valve in line to nitrator not closed while refilling weigh tank), nitric acid overflowed nitrator into drowning tank below, releasing acid and nitrogen-oxide fumes in the building. Employee, at lower level in the building, was hospitalized for observation and treatment after exposure to these fumes. Cause: Being able to open line to weigh tank while line to nitrator was not closed. Preventive Meusures: A "keyed valve handle" has been provided to operate both valve to nitrator and identical valve in feed line to weigh tank. A cover vented to outside building is being installed on the drowning line. CASE HISTORY NO. 1855 Maintenance The cover of a pressure tank used to subdivide a jellied product, suddenly came off when the tank was under 25 lbs. of air pressure. No serious injuries resulted. It was determined that one of the bolts used to fasten the cover had only 40% of its surface welded to the tank. The weld failed and the bolt fell into the tank where it w-as found. The pressure relief valve set at 30 p.s.i.g. was found to be in good condition. The plant's rigorous preventive maintenance program will be improved in an attempt to uncover similar defects in the future. The plant personnel were distressed that failure of only one bolt could have resulted in this accident. A different equipment manufacturer is being considered for the future. CASE HISTORY NO. 1853 Lockout Procedures Description Two millwrights were asked to relocate an air line after a hot patch machine had been turned about 15 degrees from ils original location. They moved a telescoped aluminum ladder into position, mounted on rubber wheels with insulated outriggers against the hot patch machine, then one went up to turn the air valve off. As he touched the air valve he was electrocuted. The shoe to the hot patch machine was being fed by 440 volts and the insulation had deteriorated and one side was lying against the metal. Preventive Measures: The use of lockout procedures had tieen stressed at every opportunity, yet was not being fol lowed. A disconnect switch on the hot patch machine was within 3 feet of the ladder, mounted on the machine. It was not disconnected. Further investigation revealed the CASE HISTORY NO. 1856 Mechanical Equipment Description: A set-up mechanic was working on a "Label-Dri" labeling machine. He reached with his left hand behind the upper hotplate which was in the forward position. He reached to hit the jog button with his right hand and hit the start button instead. Realizing his mistake, he immediately hit the stop button, but the hotplate (400F) came back and caught his hand, pinning it and holding it in the machine. Since jogging the machine would have moved it back even further, he called for another mechanic who came and freed his hand by turning the clutch wheel manually. His hand was caught for 2-3 minutes before being freed. If he hadn't hit the stop button immediately, he might have broken his arm or worse. He suffered third degree burn of his left palm and wrist, plus forced trauma and minor lacerations to his left hand. -80- CMA 048794 T 'ause: The "unsafe act" which caused this injury was 01 pushing the wrong button, but having one hand in the machine and trying to run it with the other. Preventive Measures: The job button is directly below the start button, and they are both black. A different color (ares or aluminum) should be used for jog. Also, a "1 finger inch. 2 linger run" safety circuit should be installed, as shown in ANSI B65.1-1954. CASE HISTORY NO. 1857 Vent Glass Failure i The glass portion of a dry vent failed but did not cause any injury. The dry vent had recently been installed on ! an HC1 storage tank and because they did not have the normal "DriRite" (calcium sulfate), silica gel was used, i Silica gel has a high absorption rate which generates heat. ' It was felt by the manufacturer of silica gel that the thermal shock caused by the high heat generation caused the glass to fail. This explains the tank farm operators' observation of steam coming out of the vent while he was blowing the line, just before the failure. CASE HISTORY NO. 1858 Pight Glass Failure Failure is reported of a 5 inch sight glass on the manhole cover of an oil defoamer tank. It was the accepted practice to remove the sight glass when making additions to the tank. Sight glasses should not be removed as part of normal operations. It is too much to expect that each time the correct gaskets and correct amount of torque will be used when the glass is replaced. CASE HISTORY NO. 1859 Laboratory Distillation A chemist suffered face lacerations when the distillation flask she was \sorkmg with in a hood, exploded. She was wearing safety spectacles and did not suffer any eye injury. Towards the end of this vacuum distillation, solidification occurred and the neck of the flask was being blocked. Unfor tunately a shield was not being used. This reaction is described in the literature without any indication of instabil ity and the directions were being followed. A flash fire followed the explosion when a bottle of pyridine which was stored in the hood was broken. One 5 lb. CO2 and one 20 lb. COa extinguisher put out the fire. Damage was limited to the hood and the immediate vicinity. It is fortunate 4hat this work was being carried out in the hood since this P not a sprinklered laboratory. Laboratories using flam mable materials or where new or potentially exothermicreactions can be carried out should be sprinklered to avoid a large conflagration and prevent trapping per sonnel in the laboratory. CASE HISTORY NO. 1860 Plastic Wastebasket Fires Wastebasket fires are fairly common when there are care less smokers in office areas A recent article warns against the use of plastic wastebaskets. It is noted that a plasticwastebasket fire was the cause of the 1970 nursing home disaster at Marietta, Ohio which killed 32 of the 46 patients in the one-story building. The fire was detected by an automatic fire alarm system, but as it was later reported, occupants saw the fire and assumed it would bum itself out. Smoke inhalation was the cause of the deaths of approxi mately one-third of the 32 patients. An idea of the quantity of smoke generated by burning plastic can be gained from a calculation cited by R. Stevens in the March 1972 NFPA Fire Journal. He notes that a single foot of one-inch PVC nonmetallic conduit can produce enough smoke to obscure 3500 cubic feet of room space (and enough hydrogen chlo ride to produce a lethal concentration in 1950 cubic feet!). Dense smoke can also affect the proper functioning of ele vator doors due to the fact that the electric eye cannot distin guish between dense smoke and a true obstruction. CASE HISTORY NO. 1861 Carbon Disulfide Unloading Carbon disulfide was being unloaded with nitrogen pres sure from a lank car when the flexible unloading hose broke at the coupling. Operating personnel shut the remote nitro gen valve but this highly flammable and toxic material con tinued to discharge over the unloading platform and into a sewer. The Fire Chief was called. He immediately called for a fire engine and four plant firemen were asked to respond. Two 1 Vi inch fog lines were activated to flush the vapors and the car. A hose was put down the sewer. One fireman, in full protective clothing and under cover of a fog stream, mounted the tank car and shut the discharge line. He also disconnected the line and drained all residual material. Two hundred gallons were lost but no fire or injuries resulted because the emergency was expertly han dled. Investigation revealed that the hose had been in poor condition for some time. CASE HISTORY NO. 1862 Automatic Fire Protection System Failure to deactivate an automatic fire protection system resulted in only minor injuries but highlights the need for a written training procedure such as Job Safety Analysis. Two newly hired operators were assigned to clean up milling equipment which is protected by a Fenwal Explosion Sup pression System. No one deactivated the system. One of the operators, while kneeling at the access door of the dust collector and cleaning with an air hose and rag, must have directed the air at the pressure sensor which activated and instantaneously released water spray into his face via the explosive activated device. He immediately fell or was pushed backwards onto the platform in a dazed condition and was taken to the hospital for observation. Training of 81- CMA. 048795 1 supervisors and operators was immediately undertaken. Signs and an indicator light will be installed. CASE HISTORY NO. 1863 Bromine -- Methanol Reaction Description: Wearing safety spectacles saved a chemist's eyes when bromine and methanol reacted. A young chemist was following a process, published in a highly esteemed book on biochemical preparations, which required the use of a solution of bromine in methanol. The manner of pre paring this solution was not defined and no indication of potential hazards was provided in the text. The operator chose to use a measuring cylinder and a short time after making the solution, a strongly exothermic reaction took place, ejecting the contents of the cylinder. The operator sustained bromine bums to his face around the safety specta cles he was wearing; these fortunately protected his eyes from all but a small amount of bromine vapor. Cause: Subsequent investigation showed that mixing 9 ml, bromine with 15 ml. methanol, initially at room temperature, leads to a rapid evolution of heat, the mixture reaching the boiling point in about two minutes. It appears that it was this ebullition, rather than explosive reaction, that caused the mixture to be ejected from the relatively narrow measuring cylinder. Preventive Measures: This incident underlines the necessity for extra caution when preparing mixtures for reactions for the first time. It also shows how vital it is for workers in chemical laboratories to adopt adequate eye protection. This also highlights that descriptions of preparations in prac tical text books normally don't incorporate information about potential hazards, and chemists should be cognizant of this failing before proceeding. CASE HISTORY NO. 1864 Pickup Truck Accident Description: Two technicians were involved in a pickup truck accident while returning from the Utility Area to the Main Plant Control Room. The truck struck a road barricade in the Solvent Unloading Area. The road barricade was of the railroad semaphore type, and the bar was designed to be raised and lowered manually, being balanced in posi tion with counterweights. On this occasion, the barricade foundation had been damaged and the bar was pointed at an angle rather than perpendicular to the road. The end of the barricade bar pierced the windshield in front of the steering wheel, passed diagonally between the two tech nicians and out the right rear comer of the cab. Both men received minor injuries. Cause: At the time of the accident it was dark, but the area was well lighted and the visability and road conditions were good. The foundation of the barricade had been dam aged and the barricade bar had rotated to an angle position to the road. The two technicians involved in the accident had earlier noticed that the barricade bar was turned and protruding several feet into the road. Investigation also revealed that the barricade had not been in proper working order for some time. The causes for this accident can be stated as follows. 1. Poor Attitude. Many people failed to respond to the obvious hazard created by the barricade when the foundation was damaged, allowing the barricade bar to swing horizontally. 2. Poor Work Practices. Driving too fast to keep the truck under good control and failure to properly secure the swinging barricade. Preventive Measures: 1. Repair the barricade so that it does not rotate horizon tally but will only raise and lower as originally designed. 2. Install reflectors on the barricade arms so that they can be more easily seen. 3. Review the plant safety rules on driving with each technician. CASE HISTORY NO. 1865 Communications Lapse Description: Employee transferred acetic acid solution into tank containing acetic anhydride. Although he did not physi cally check the tank, he believed it empty as indicated on previous-shift log. A violent chemical reaction generated fumes which escaped through a hinged manhole cover, engulfing one end of the building. Six employees sustained minor injuries; one employee's eyes were sufficiently irritated to require loss of time from work. Cause: Inadequate communication during change of shift. Preventive Measures: The importance of accurate inter-shift communication is being stressed; and study of evacuation procedures, exits, and escape routes is under way. CASE HISTORY NO. 1866 Acid from Drum Description: Two operators were burned on the face, neck and forearm with concentrated nitric acid. They both were wearing goggles which saved their eyes. Needing some nitric acid for cleaning purposes, the operator started to place a drum on its side on a pallet. The other injured man came to assist. The side bung of the drum was being opened when internal pressure forced the acid out, spraying both men. Preventive Measure: The safe procedure is to loosen the small end bung to release pressure and then close it, screw a self-closing spigot in the large end bung and then with a drum tilter to put the drum in a horizontal position. -82- CMA 048796 1 CASE HISTORY NO. 1867 CASE HISTORY NO. 1870 ilter Maintenance Delivery Error Description Pressure forced molten polymer out around the bolt threads when the bolt was loosened to remove the filter dements. The employee suffered second and third degree burns to the face and forehead. Cause: Failure to release pressure prior to breaking flange. Preventive Measures: 1. An aluminum shield has been fabricated to be placed over the filter element prior to changing. 2. Safety procedures were reviewed and revised accord ingly to insure that pressure is relieved before attempt ing to remove the filter element. 3. Face shield will be worn when changing filters. CASE HISTORY NO. 1868 Ladder ; Description: Employee was working from a ladder, standing i on the 6th or 7th rung, hacksawing a 1" conduit and since i the hacksaw was binding, he pulled on the conduit and | the conduit gave way, causing him to lose his balance and | fall from the ladder to the floor. He suffered fracture of | right wrist, a severe contusion to the right orbit with ! ^^Jssible fracture of the malar bone, a large laceration of | the right aspect of the forehead, severe contusion to the J right shoulder and a severe concussion. ij 1 Cause: Had employee been using an 8' stepladder and a i saber-saw, he would have been in position to cut with his | right hand and have his back against the wall so that he i would be pushing against the conduit rather than pulling, i Employee was using both hands above his head and obvij ously any sudden motion could and did result in loss of balance. Preventive Measures: The importance of being aware of position and the possibility of imbalance was stressed with all personnel. The use of a safety belt and hook for ladder work requiring the use of both hands, and when only such a ladder can be used to carry out the job, will be investigated. CASE HISTORY NO. 1869 Cyanuric Chloride in Exothermic Reaction Description: A chemical company experienced a fire and explosion when an exothermic reaction built up pressure in a vessel. The gases leaked into the room when the head gasket was displaced, and found a source of ignition. There e no injuries but there was extensive glass and roof lage. The exotherm occurred when the batch was held, instead of being processed immediately. At 30C the reac tion of cyanuric chloride and water (or alcohol) is highly exothermic and evidently that temperature was reached. Description: A vendor's error resulted in oxygen contamina tion of liquid nitrogen tanks which could have had some serious consequences. Deliveries are made by tank truck to three 1200-gallon plant nitrogen storage tanks. The ven dor's truck was used for both nitrogen and oxygen deliveries. Vendor procedures, which were not properly followed, re quire purging the tank truck with nitrogen prior to each nitrogen loading. Apparently the truck was filled without purging and a large quantity of oxygen remained in the tank. Subsequent delivery resulted in oxygen-enriched nitro gen being pumped into two of the plant's nitrogen storage tanks and into the vendor's local bulk storage tank, from which nitrogen was obtained for filling Dewars (insulated metal laboratory bottles). The error was discovered when alert lab technicians reported a strange bluish hue in the liquid nitrogen taken from the two systems. Investigation also revealed oxygen contamination of nitrogen in some Dewars. No injuries or serious incidents resulted although the potential was great. Preventive Measures: Immediate action taken consisted of the following: 1. The contaminated systems were purged with liquid nitrogen, including the vendor's local bulk storage tank. 2. Tank truck contents will be analyzed prior to transfer into the storage tanks. 3. All Dewars are being verified for proper contents by hydrometer (specific gravities of liquids: nitrogen, 0.808; oxygen, 1.14; argon, 1.4). Further actions under consideration are: 1. Require vendor to use one truck only for liquid nitrogen. 2. Fill all Dewars from a plant storage tank, the contents of which have been analyzed, rather than from the vendor's local storage tank. CASE HISTORY NO. 1871 Hot Stuff Description: 300F monomer in a straight sided, eight ounce glass jar was being transferred with hand-held tongs by a laboratory technician when the jar slipped downward com pletely breaking. Monomer contents splashed upward out of the open jar top onto the technician's lab coat sleeve as well as unprotected lower leg causing painful bums to the arm and leg. Quick action by lab associates in applying cold water compresses to the bum areas and subsequent medical atten tion is credited with minimizing the bum effects and enabling the girl to return to work the following day. Preventive Measures: An on-the-spot review by safety and lab personnel immediately following this injury accident produced the following ideas that are now being analyzed for implementation: 1. Flared tops for all tong-carried vessels to prevent total slip-through. -83- CMA. 048797 2- Preset locking tongs to overcome possible hand mus cle relaxation as a contributory problem. 3. Elimination of any tongs of flimsy construction to prevent twist or override action on objects being held. 4. Adequate, properly constructed protective outer lab garments and face shields. Such garments to be heat resistive for a reasonable duration following direct heat contact. 5. Properly designed transparent lab bench shield. 6. Different method other than heat to render monomer fluid, such as use of a safe solvent. screwed a cap to the threaded end of the pipe, below the valve. This stopped the leak at that time. He removed his splash goggles and replaced them with standard spectacles and proceeded to his next operation. Some time later, the employee returned to the tank to retrieve the wrench he had left there. As he reached for the wrench, his head was underneath the valve assembly and 2 or 3 drops of the liquid struck him on the left cheek and right eye. After flushing the eye in the department and after first aid treatment in the Plant Dispensary, the employee was transported to an eye specialist for further examination and to the hospital for further treatment. CASE HISTORY NO. 1872 Flash Fire Involving 152MM Cartridges Description: To prevent absorption of moisture, elastomeric barrier bags are installed over the nitrocellulose cartridge cases of 152MM cartridges. This is normally done on an indexing conveyor with the use of a mandrel. Alternate procedures permit the installation of the bags on rounds that are in skid racks. A skid rack of 24 rounds had been brought into the assem bly bay from the oven bays. Two production operators were preparing to install elastomeric bags over the cartridge cases. Twenty elastomeric bags were being dumped from two plas tic bags onto the top of the cartridge cases. One operator was distributing the bags on top of the skid of shells when a loud popping noise was heard and a flash of fire occurred. Operators were wearing conductive shoes, flame-proof clothing and eye protection, and were standing on grounded plates. Two contractor employees sustained minor bums to face, wrists and hands. Cause: 1. Exact cause -- unknown 2. Possible cause: a. Pinching action caused by downward pressure against a loose ignition element and loose explo sive in the ignition element well. b. Ignition of adhesive (containing M-8 propellant which contains 4391 nitroglycerine) by static spark. 3. Indirect cause: Failure to recognize hazard associated with distributing material on top of cartridge cases. Cause: An investigation revealed that the caustic solution was dripping past the cap. Preventive Measure: The defective valve on the tank has been replaced. CASE HISTORY NO. 1874 Two Employees Receive Electrical Shock Description: Two employees were slightly injured (first and second degree bums to fingers and palm) by an electrical shock while cleaning an extruder. The extruder had been shut down due to excessive leakage of melted compound around the extruder head. The melted compound had flowed back around the heating zone on the outside of the extruder barrel. The employees involved were using a crowbar to pry loose a large piece of material from around the zone heater. The crowbar hit and shorted out the discharge side of the heater terminal wires, at which time the employees received the electrical shock and minor bums. Cause: The melted compound had flowed over and obscured the wires to the heater and the electrical circuits to the heater had not been locked out or disconnected prior to starting the cleanup. Preventive Measure: All employees were re-instructed on the lock-out procedures with special emphasis placed on the locking out of non-moving equipment. Also, corrective measures to eliminate leakage around the extruder head are being intensified. Department of Defense Explosives Safety Board Case His tory CASE HISTORY NO. 1873 Eye Burn Description: An operator sustained a chemical bum to the right eye when he bent down to pick up a wrench he had used to tighten a leaking caustic valve. While wearing splash goggles, the employee had discon nected a stainless-steel flexible hose from the bottom outlet of the tank. He noticed that the main bottom outlet valve of the tank was leaking slightly and caustic solution was dripping from the tank to the floor. Using a wrench, he CASE HISTORY NO. 1875 Operational Error Description: Injured was attempting to pump finished Silicate Solution from the dissolver and was having trouble. Apparently, he disconnected the transfer hose without shut ting the valve from the dissolver and was struck by the hot solution. The material hit his right arm and leg and ran down into his boot inflicting second and third degree burns on his right foot and lesser injuries to his arm and leg. Cause: Failure to follow proper safety procedures prior to disconnecting the unloading line. -84- CMA 048798 Preventive Measures: . Modification of unloading facilities to permit employee to break line from outside immediate area, being investigated. 2. Rubber protective equipment provided, to be worn anytime the pit area below the dissolver is entered. 3 All employees re-instructed on procedures for pump ing off a dissolver. CASE HISTORY NO. 1876 Disconnecting Line Under Pressure Description: Injured was loading a tank car with Methyl Chloride. When he finished loading, he started to disconnect the loading line without bleeding the pressure off and was sprayed on both legs. After showering and being treated at first aid, no injury was apparent. By the end of the shift however, a number of small blisters had developed on both legs. The man was again treated at first aid and then sent to the hospital for precautionary check. There, it was decided he should be admitted. Cause: 1. Failure to properly vent loading line. 2. Failure to follow established job procedures. Preventive Measures: _ 1. Job procedure reviewed, no modifications necessary. M2. Injury and procedures to be reviewed with employee ^ when he returns. 3. Injury and procedures to be reviewed with all plant gangs. CASE HISTORY NO. 1877 Sulfuric Acid Burns Description: During start-up of sulfuric acid plant, when conditions were upset, a high level in an oleum pump tank was indicated by the bubbler gauge. The indicated level, however, was not excessive. Also, acid was leaking around the submerged pump packing but this was attributed to acid trapped in the packing during a previous high level period. Injured suggested to foreman that he measure the level using a dip stick. To do so, he proceeded to remove the cap on a 2" nipple on the top of the tank (which is part of a closed system). As the cap was removed, sulfuric acid blew' out, spraying the injured on the arms, chest, stomach and legs. Cause: 1. Failure to recognize danger signs and having high level alarm disconnected. 2. Personal protective equipment not worn when opening a closed system. 3. Bubbler gauge failed to show actual level. Preventive Measures: 1. A Job Safety Analysis will be developed for this job and all operators instructed accordingly. 2. High-low level alarms will be left operative during start-ups. 3. Personal protective equipment requirements will be reviewed with all personnel. 4. Install valve in tank top piping to check for high level in safe manner. 5. Investigate more reliable level indicator. CASE HISTORY NO. 1878 Tank Truck Loading Description: Injured was loading a tank truck with caustic soda. While attempting to measure the tank outage, he bumped the loading line which came out of the dome and splashed hot caustic onto his leg. The caustic ran down into the man's shoe and caused deep bums on both sides of his right ankle. Cause: 1. Failure to secure the loading line to the truck dome. 2. Attempting to measure outage without shutting off the loading line. Preventive Measures: 1. Re-instructed employees on safe procedures for load ing and measuring trucks emphasizing tie-down of loading lines and shut off product flow before measur ing tank outage. 2. Review accident with other employees at safety coun cil meetings. 3. Safety instructions for acid and caustic loading being revised. CASE HISTORY NO. 1879 Hose Rupture Description: A corrugated, stainless steel flexible hose with braided shielding ruptured, releasing approximately 300 pounds of vinylidene. A scale tank had been filled with vinylidene through the flexible hose involved, and a nitro gen blanket had been applied on the previous work shift. Cause: The flexible hose that failed was a type that had proven to have short service life in this type of service. Preventive Measures: All of this type of flexible hose is to be replaced with a Teflon-lined stainless steel hose. CASE HISTORY NO. 1880 Chlorine-Caustic Reaction Description: Employee was emptying a liquid chlorine pipe by feeding the vaporized chlorine through a flexible tube into an open container filled with 20% caustic. He was asked by a lab man to fill about 10 cm3 liquid chlorine into a Dewar flask. Residual chlorine in the Dewar was not needed. As the employee did not know what to do with this chlorine, he poured it into the caustic container. -85- CMA 048799 This caused a reaction and employee got some drops of the splashing caustic on his right instep. He suffered a second degree bum on his instep despite proper washing procedure. Employee was wearing full face protection, Neoprene cloth ing and safety shoes. Cause: 1. Employee was not sufficiently informed about the reaction of liquid chlorine and caustic. 2. Employee's feet were not sufficiently protected against hazardous liquids. 3. The lab man left the employee -- without taking care of the liquid chlorine in the Dewar. Preventive Measures: 1. Everyone handling caustic will wear rubber boots. 2. Operators will be trained in chemical reactions. 3. Lab people will receive safety training. the exposed areas (arm and neck) with a nearby water hose. He did not use the safety shower which was 21 feet from the sample valve. He then went inside the control room to his locker and changed clothes. He returned to the vicinity of the vessel where he saw a fellow operator and asked if phenol "is the stuff that will kill you." When he said "yes", the employee showed him the burned area of his arm. The employees then reported to the shift foreman. The injured employee was sent to First Aid on a bicycle and the emergency vehicle was not called. Time involved from time of exposure to reporting to First Aid is estimated to be twenty minutes. The employee was showered and the bum area washed with alcohol in First Aid and then transferred to the hospital for examination and treatment. A plastic surgeon was called in on the case to determine if a skin graft would be required. At this time it does not appear that a skin graft will be necessary. CASE HISTORY NO. 1881 Tank Explosion and Fire Description: An explosion and fire occurred in a 10,000 gallon, agitated dissolving tank. The tank had been pumped empty of the rubber-monomer solution just prior to the explosion. The tank is an open-vented tank and the agitator was kept running per the normal practice. It is apparent that the agitator coupling failed, allowing the agitator to drop into the tank causing a spark. The temperature in the tank was 32C. Damage was confined to roof and building panels over the dissolving area, a broken pedestal support for the agitator gear box, smoke and fire damage to paint, and the rubber conveyor, and minor wiring loss. Cause: 1. Explosive concentration of monomer in agitated tank. 2. Failure of coupling on agitator, allowing agitator to drop in tank causing a spark. Preventive Measures: 1. Develop and install suitable inert blanketing system to positively insure O2 level is too low for explosion or fire to occur. 2. Completely overhaul agitation system. Provide more positive device to keep agitator from dropping. 3. Provide continuous O2 monitor and alarm system on inert blanket. CASE HISTORY NO. 1882 Hose Failure Description: The sample valve was located directly on the bottom dish of the tank and was equipped with a short nipple and hose connection. No drain funnel was installed. He attached a 3/4 inch hose to the valve and ran the other end over to a grating on an open sump. When he opened the valve he was sprayed by recovered phenol from a break in the hose approximately 12 inches below the valve fitting. The operator immediately rinsed Cause: 1. Poor sampling procedure. Proper means for flushing sample line and disposing of liquid were not provided. 2. Using a defective hose. Break in hose was conspicu ous and was in the very area held to affix the hose connection. 3. Failure to comprehend the danger of recovered phenol and failure to report and seek immediate proper first aid. Preventive Measures: 1. Sample pot will be installed with a pipe drain to a five gallon waste can. 2. Hoses will be checked monthly by simple tap water pressure. Defective hoses will be removed. Inspection of hoses will also be made at time of use, 3. All personnel in the unit will be given a review1 of the danger of phenol. The employee had been trans ferred into the unit two months before and had received safety indoctrination into the unit. CASE HISTORY NO. 1883 Improper Line Opening Description: An 18 year old laborer was melting a heel of product in a tank car. He used a 3/4 inch hose from a four station steam manifold and connected it to a 3-inch hose which was in turn connected to the bottom outlet of the car. Upon completion, he closed the valves on either end of the hose, at the manifold and tank car, thereby trap ping steam in the hose line. Reportedly, he waited ten minutes, assuming condensation would relieve the pressure. He then opened the hose connection and residual steam pressure splashed him with hot condensate causing first and second degree bums to the front of body, arms, legs, and abdomen. Preventive Measures: Normal practice is to vent the hose through an idle hose connection on the manifold. In this case all four connections were in use. However, it would still have been relatively simple to vent through one of the connected hose lines, though this may not have been obvious to the employee involved. -86- CMA 048800 CASE HISTORY NO. 1884 echanical Equipment Description: A resin compounding unit consists of a mixer, a cooler and a blender. The batch is dumped successively from one to the other through identical piston valves. The mixer and cooler are similar vessels with high speed rotating mixing blades. On the night of the accident, the operator suspected that the valve from the cooler to the blender was clogging. He shut the "mixer" motor off and opened the cooler's piston valve by throwing the switch into "manual" position. Then without shutting the "cooler" motor off, he loosened the bolts and removed the cover over the valve's piston. The operator then reached inside and started pulling material down the discharge chute. He reached in too far and the cooler mixer blades caught his glove and severed the middle and ring fingers. Cause. 1. Operator should not have removed piston valve cover. The clogging should have been reported to supervisor and a maintenance man called to handle the problem. 2. The operator failed to follow written safety procedure which calls for supervisor personally shutting off all power and compresser air and the mechanic locking out the electrical controls. Preventive Measures: The safety procedure has been amplified to prohibit removal of valve covers and has been posted at the machine. All personnel have been reinstructed and operators given the safety procedure (including mechanical work) for the unit. ! CASE HISTORY NO. 1885 Welding Fatalities -- The Drum Hazard Description. From a newspaper report: A welder died in a city hospital where he was admitted for burns suffered in an explosion which instantly killed a companion worker. Authorities said a 55-gallon drum filled with an unidenti fied chemical exploded, killing one worker and critically injuring another who was admitted to hospital suffering from third-degree bums over 60 percent of his body. He died at 3 A.M. the next day. i A plant spokesman said the two welders were working ; on an isolated second floor balcony at the textile equipment plant, installing a mixing tank when a nearby drum exploded. The insurance company which reported this incident com mented as follows: In addition to this dram explosion, our company has received, in the last few months, injury acci dent reports on six similar explosions, and there must be ^jnore that do not result in personal injury. The ones reported ^^^kere not as serious as this one, but the potential was just great. In the past few years we recall one such case that caused a welder to become a 100 percent permanent total disability and another incident that resulted in a 70 percent permanent disability. Such incidents can occur in two ways: 1. When people attempt to burn the head out of a drum that contained a flammable liquid. 2. When drums which contain, or have contained flammables are used as temporary work benches for welding or cutting operations. The ignition of the fumes in such a container can occur even though the flame has not cut through the steel shell. The autoignition temperatures of various solvents or fuels vary from about 400F to 1000F. The softening point of steel is far above these temperatures so that the autoignition temperature can be reached within the drum long before the steel even reaches red heat. The violence of the explosion depends on the fuel-air mixture, and on the strength of the container. A drum with a fair amount of liquid may have a rich mixture and result in a mild explosion, while an almost "empty" container may have an ideal mixture and a very strong explosion would result. A drum that is old and corroded may fail early and release the gases before the pressure builds very high, while a sound drum with the bungs in place can confine the explosion slightly longer, permit higher pressures to build and therefore result in a much more violent release of the energy. Preventive Measures: Never use any flames on or near drums which contain, or have contained flammables. If drum heads must be removed, the container should be filled with water, the bungs left open, and the cutting done by mechani cal means. Such drums should never be used as "work benches" especially if welding, cutting or other operations that will produce heat or sparks are to be carried out. READER'S COMMENTS (a) "Your statement relative to autoignition temperatures could be dangerously construed. Carbon bisulfide (CS2) has an autoignition temperature even below the boiling point of water -- 212F or lower. "Hence, steam directed at a vessel containing explosive mixtures of CS2 in the air (19fr-50CT-) could cause a disastrous explosion. Since CS2 is not an uncommon solvent, your readers should be alerted to this possibility." (b) "Preventive measures should include a listing of `safe practice' material; e.g., American Welding Society's publication A6.0 -- "Safe Practices for Welding and Cutting Containers That Have Held Combustibles" ANSI Z49.1 -- "Safety in Welding and Cutting" NFPA 327 -- "Standard Procedures for Cleaning or Safeguarding Small Tanks and Containers" National Safety Council -- "Accident Prevention Manual for Industrial Operations" Union Carbide Corporation -- "Precautions and Safe Practices in Welding and Cutting with OxyAcetylene Equipment" CASE HISTORY NO. 1886 Laboratory Flash Fire -- Student Burned Description: Concluding a distillation procedure, the student removed the Bunsen burner from beneath the flask of tertbutylbenzene and began to disassemble the distillation equin- -87- CMA 048801 ment. She had removed the stopper from the flask and was working on disassembly. She had approximately 30 ml of tert-butylbenzene in a 100 ml beaker. It appears that the flammable vapor being given off from the open flask was ignited by the open flame of the Bunsen burner. This ignited the flammublex in the 100 ml beaker. These flammables were then spilled, splashing on her chest, arms, abdomen and face Flammables also splashed on the floor and the work table, Some of the students then grabbed a COs ex tinguisher and two fire blankets, covered the student with the fire blankets and extinguished the fire with the CCh ftre extinguisher. They then began rendering first aid. At the time of the accident the student was wearing ordinary street clothes and safety glasses of the plastic visitor spec type with side shields The Associate Instructors do not allow people to work in the lab without safety glasses. The safety glasses were burned black and she received hums to the chin and mouth area, but due to the safety glasses, her eyes were not injured. Preventive Measures: 1. Electric heating mantles should be used for heat source to prevent the need for open flame when heating hazardous and highly combustible materials. 2. Flame retardant lab coats and/or aprons should be required where there is hazard of splash by hazardous chemicals. 3. Full face shields should be provided to protect not only the eyes, but the entire face. CASE HISTORY NO. 1887 The#followtng is excerpted from a report by the City of Los Angeles on the August 8, 1972 fire at the San Pedro General American Transportation Terminal. This is a facility for storage and transfer of petrochemicals for more than 20 of the largest chemical companies in the country. Description of Facility A. Tank Farm <Started 1967) a. Two diked areas 44 ft. wide. North one 470 ft. long and south one 490 ft. long located end to end running north from 22nd St., containing 31 tanks in the north dike and 4! in the fire-involved south dike. b. Dikes of reinforced concrete 6 in. thick, 30 in. high, designed to contain about 100,000 gals, of liquid with drain valves. c. Vertical steel tanks in the south farm 12-18 ft. in diameter, ranging in height from 30-36 ft., in capacity from 30,000-80,000 gals., with exotic flammable liquid contents ranging from acetone (F.P.-2) to Texanol (F.P. 325-445). B. Driveway Area a. Concrete 22 ft. wide, 900 ft. long with drainable sumps and 2 railroad spurs running full length in gravel bed 30 ft. wide. b. Loading pipes of 3" steel pipe rising to a height of 12 ft. from the base of the tanks inside the dike and projecting 90 out over the driveway for a distance of 8 ft. with a filler connection projecting downward various lengths to provide a ground clearance which varied from 11 '4' ` to 12". c. Pairs of 4" deep hose troughs 1 ft. apart crossing driveway at various intervals. General Description of Fire A. Origin 1. While pulling into position in the driveway on the east side of the south tank dike, an unladen tank truck bounced on the concrete surface catching either the tank, exhaust pipe or an open hatch on a filler pipe, shearing off the pipe inside the dike and starting a flow of flammable liquid believed to be acetone. This was due to the fact that the control valve at the base of the tank was in an open position. Possibly more than one filler pipe was damaged by the collision. 2. Ignition occurred at this time probably from the truck's engine or exhaust causing the driver to flee. B. Fire Progress 1. Fire quickly spread in the dike area engulfing 3 tanks, one of which exploded as the first-in officer arrived. The front end of the tank truck was also involved outside the dike on the east side. 2. As first-in companies set up operations, fire spread north and south in the dike area exposing adjacent tanks. A tank exploded as lines were being laid into the fire by the first-in companies. 3. A southwest wind 10 m.p.h. tended to extend the fire mostly northward as more tanks lost their tops and others became surrounded by ground fire. 4. Slop over from rupturing tanks and hose streams spread ground fire outside the dike on the east side exposing railroad tank cars loaded with urethane and alcohol and the wooden loading dock roof on the warehouse. The tank truck was totally involved. 5. Fire continued spreading northward in the dike with more tanks rupturing and blowing their tops off until, at 1 hour into the fire, a 36 ft. high, 30,000 gal. truck containing 10,464 gals, of jet fuel additive, tore loose from its base and spewing flaming liquid, rocketed to a height of about 250 ft. before crash ing down on a tank car and the loading dock roof of the warehouse some 75 ft. away. This spread some ground fire outside the dike on the west side and increased the ground fire on the east side. 6. Ground fire on the east side enveloped four of the railroad tank cars while their tank vents were blaring like locomotive whistles. Wooden parts of the loading dock were scorching. 7. At this point sufficient water, liquid foam, powder foam, and especially light water, were brought to bear to reverse the course of the fire and eventually extinguish it. C. Total time of actual fire was 3 hours. D. Damage 1. Over $ 1,000,000 to facility -- (probably a conserva tive estimate). a. 21 storage tanks destroyed or damaged b. 4 railroad tank cars badly damaged c. 1 tank truck totally destroyed d. Loading dock roofs damaged by rocket tank e. Driveway and dike wall damaged f. Many pipes, valves, pumps, and motors damaged -88- CHA 048802 CASE HISTORY NO. 1888 taustic Corrodes Aluminum Thread Description: A chemical operator was sprayed with caustic (NaOH) as he left the north door of a production department building. The pressure gauge on the NaOH pump corroded away and sprayed about 250 gallons of caustic over the area. The gauge let go just as the operator was leaving the building and sprayed him in the face. He washed off the caustic but suffered several small burns on the face. The area was flushed down with water. The operator was wearing safety glasses in accordance with the plant-wide eye protection policy. Cause: The cause of the accident was the installation of a pressure gauge which, upon investigation, had an aluminum threaded connection which was corroded away by the caustic. Preventive Measures: 1. Pressure gauges in caustic and sulfuric acid service were checked to be sure all are 316 stainless steel. Those that are not are being replaced with 316 stainless steel gauges. 2. Mechanics and supervisors will be notified that only 316 stainless steel gauges are to be used in caustic and sulfuric acid service. Stainless steel gauges are marked on the face of the gauge as being 316 SS. 3. Gauge storage area will be marked for the non-stainless gauges as "Do not use in acid or caustic service". 4. The caustic pump will be shielded to prevent spraying in the area of the door to the production department. READER'S COMMENT This case history states that only 316 stainless steel gauges are to be used in caustic and sulfuric acid service. In my book on materials of construction, the use of 316 stainless steel is questionable in dilute sulfuric acid service. Complete details concerning conditions of service should be known before selecting grades of stainless steel for resistance to these media. CASE HISTORY NO. 1889 Employee Opens Wrong Valve Description: The bottom valve on #36 polymerization ves sel was opened by mistake, allowing approximately 4,000 pounds of vinyl chloride to enter the sewer system. A relief operator was cleaning #35 poly and in preparing for further mechanical cleaning, he left the third floor and proceeded to the second floor. However, the employee went to the adjacent poly #36 instead of poly #35, removed the "Do Not Open" tag, connected the sewer hose and opened the bottom valve. |nse: Employee stated he became confused and thought te "Do Not Open" tag had been left on by mistake. Preventive Measure: Disciplinary action was taken for the unauthorized removal of the "Do Not Open" tag. CASE HISTORY NO. 1890 Waterblasting Description: Employee was waterblasting polymer inside the fire wall of tank farm. He was using a waterblaster gun with deadman control which had a three foot lance with a fan nozzle. The operating pressure was 4.000 lbs. The employee had on steel toe safety boots and a face shield, but he was not wearing metal foot and lower leg guards as per prescribed procedure. Employee was slowly backing up inside the tank farm when he felt something nudge him in the back, and he looked back over his shoulder. He either raised his right foot slightly for balance or he passed the nozzle over his right foot. However, in looking back he failed to release the deadman lever which would have shut the pressure off. He suffered deep laceration with puncture-type wounds of the right foot. Cause: Failure to wear prescribed protective equipment. Preventive Measure: Employees will be reindoctrinated in waterblasting procedure. CASE HISTORY NO. 1891 The following has been received in response to a request for additional information on the disposal of potassium waste. Disposal ofPotassium Waste -- Potassium metal was manu factured in the 1941-1944 period. The metal was oxidized to K2O4. Much work was done on disposal of waste material during the development of a process to make a potassiumsodium alloy. Various amounts of the K-Na alloy were produced and ultimately disposed of safely, using the open pit burning method of disposal. With this method, it is important that proper personnel protection be wom by the operators doing the burning. Care must be exercised during burning so that combustion is complete and so that free metal and oxides are prevented from being present, as they react most vio lently on contact with each other. Potassium metal (in 50 lb. quantities) was stored in purged metal containers. Each container had 2% " pipe plug connec tors to be used for filling the containers and also for draining the potassium into the burning vessels. It was found that live steam was a safe and satisfactory means of cleaning these containers. The steam line was blown to clear all condensate then inserted in the storage container and steam flow started slowly. The disposal of the potassium-sodium metal in the storage vessel was complete, very rapid and safe. Tare weights were kept of all containers to insure that large amounts of potassium were not left in the storage cans. All containers were completely dried and purged for reuse. To clean small tools and pipe fittings that were con taminated, a steel box was fabricated using 1/4" plate with many 1/4" holes drilled in the top and sides as venting areas. A heavy cover with a strong latch was included. A wire tray for supporting the equipment to be cleaned. -89- CMA 048803 was placed in the box. The tray was above the bottom of box to prevent contact with any water that might possibly be in the bottom of box. Two steam lines were connected to the box and the steam lines were cleared of condensate. The box was inspected until found to be dry. The contaminated equipment was placed on the wire tray, the cover closed and pinned, and the steam flow started from a remote spot, preferably from behind shield. Depending on the amount of K to be disposed of, the steam was left on 30 minutes or longer. This method has safely disposed of larger amounts of K, not readily disposed of in an alcohol or alcohol water solution. Cleaning Distillation Column -- During this same period, a process was developed for the manufacture of K by distilla tion from potassium salts and metallic sodium. To clean the distillation column, a steaming procedure was successfully used. The process consisted of a nitrogen purge started on the column with the vent line blowing on a gas flame. The steam line was blown free of condensate and introduced slowly into the column. A burning increase was observed as the vent increased in hydrogen content. Steam flow was regulated to maintain a steady flame. The nitrogen purge was continued. When the vent gas no longer had enough hydrogen to sustain a flame, it was considered clear and at that time the steam was increased and continued for an 8-hour period. The distillation column was success fully steamed many times using this method. CASE HISTORY NO. 1893 Hydrazine Laboratory Fire Description: In polyester tests, fiber samples are boiled over an electric hotplate in a glass beaker containing 25-3o cc of 64% hydrazine. The procedure calls for use of glass rods for handling the sample. In this case, the laboratory technician used a pair of metal tweezers, which were old and somewhat rusty. When the tweezers were put into the hot hydrazine solution to remove the samples, the hydra zine ignited. The fire remained within the beaker and there was no damage or personal injury. Cause: Autoignition of hydrazine in the presence of iron oxide introduced on the tongs. (See NFPA #49, Hazardous Chemical Data. The ignition temperature for hydrazine varies -- being 75F in the presence of iron oxide and 518F in a glass container.) In the presence of iron oxide, the autoignition temperature of 75F is below the normal flashpoint of 100F. The technician involved in this incident was not aware of this unusual characteristic of hydrazine. Preventive Measures: 1. Modify procedure to emphasize the need for using glass utensils with hydrazine. 2. Publicize the hazard data regarding hydrazine. 3. Select laboratory equipment with minimal iron content (such as a ceramic-top hotplate) when working with hydrazine. CASE HISTORY NO. 1892 Ladder CASE HISTORY NO. 1894 Description: The injured was insulating a water line on the bottom side of a pipe gallery adjacent to building. He was working from an extension ladder which was leaning against, but extending above, the guttering of building. The ladder slid along the gutter and fell to the ground. The injured grasped the water line and hung on for a few minutes or, in his words, as long as he could. He dropped to a blacktop surface, landing on his heels. The drop was approximately twelve feet. He suffered compressed fracture of first, second and third lumbar vertebrae and fracture of right heel. Cause: The injured violated the safety rules and practice of working alone on a forty-foot extension ladder without it being lashed in place. His co-worker, who was his safety look-out. left the job at the request of a pipefitter and without the authority of his supervisor; however, he did try to get the injured to leave the job and go with him, Preventive Measures: Appropriate reinstruction and orientaJon will be given the injured at the earliest date. His co worker this date and all Mechanical Department employees will have a meeting to re-emphasize the safe working pro cedures when using ladders and scaffolds. Suspected Phosphate Poisoning Description: Mechanic was repairing rollup door when dust containing parathion sifted down from cover above door, getting on his clothing and skin. He became nauseous a few hours later and a blood check revealed a moderate cholinesterase depression. Cause: Dust under protective cover for door was not noticed when room was cleaned. Preventive Measures: 1. More attention will be paid to the possibility of toxic dusts being dislodged from normally inaccessible places. 2. Lab checks will be made on questionable dusts prior to work exposure. 3. Mechanics have been reinstructed on hazards of para thion and proper handling procedures. READER'S COMMENT Parathion is a derivative of thiophosphate but to label a suspected parathion poisoning as a phosphate poisoning is misleading to say the least. -90- CMA 048804 CASE HISTORY NO. 1895 ten Sulfur Burns Description: Injured was assisting three other employees in cleaning a sulfur filter. At the time of the accident, the injured man and another employee were trying to open the bottom clean-out port of the filter. When the door flew open, the man was struck by a stream of molten sulfur which inflicted bums on his head, neck and arms. Cause: 1. Lack of awareness as a result of inexperience. 2. Failure to wear full protective equipment. 3. Failure to keep safety devices intact. Preventive Measures: 1. Job Safety Analysis to be written on the job. 2. Inspection and review of filter and platform facilities. 3. Re-instruction of concerned employees on job proce dures and protective equipment required. 4. Accident reviewed with all employees. CASE HISTORY NO. 1896 Amputation of Ring Finger Description: The injured was attempting to close a malfunc tioning 1/2" rising stem gate valve which was attached to a rotary steam drier. While closing the valve, the stem ^^ked under the ring on his left hand and as the drier ^^Red, the man's finger was stripped off from the second knuckle. The balance of the finger had to be surgically amputated. Cause: 1. Wearing of ring and not using proper protective equip ment (gloves). 2. Malfunction of the non-condensable vent valve on the drier. 3. Lack of awareness in a hazardous area caused by the rotating drier and escaping steam. Preventive Measures: 1. Install non-rising stem valves on all the vent lines and align them so the stem is perpendicular to the drier shell. 2, Emphasize to all personnel the importance of wearing proper protective equipment. READER S COMMENT A recommendation contained in this Accident Case His tory was directed towards the removal of all rising stem valves from vent lines. This is contrary to accepted safe practice in the chemical industry. Normally, rising stem valves or valves that otherwise are self-indicating as to their position are recommended for use in all venting systems in order that the position of the valves may be ascertained by visual observation. The use of non-rising stem valves ^Mlves that do not indicate their position by visual observa^Brin a vent system can lead to unsafe conditions wherein valves may be closed when they should be open. Reposition ing the existing valves in this instance would probably accomplish the desired correction. CASE HISTORY NO. 1897 Acrylonitrile Burns Description: One of the duties of the Floater operator is to take samples at various points around the Purification Area. This area was covered by liquid to a depth of several inches due to a blockage of the Purification paving runoff sewer drain by polymer from the Waste Water Column during chemical cleaning operations on the two previous days. Pressure cleaning of A6 Reboiler on the morning of the accident caused additional flooding and acrylonitrile polymer. The injured stepped into the pool of liquid, which he believed to be uncontaminated water, when moving between sampling points. He worked a double shift, finishing at 06.00 hours on the 7th during which time he did not experi ence any symptoms of irritation or discomfort. He first experienced irritation the next afternoon and by late after noon blisters had formed and burst. The foot condition was attributed to acrylonitrile burns. Cause: 1. Failure to conform to site instructions which require rubber foot protection when working in a flooded area. 2. Failure to clear a drain blocked by polymer sediment. Preventive Measures: 1, Reinstruction of all persons concerned that rubber boots are to be worn in flooded areas. 2. The provision of a removable trap to prevent solids and semi solids from entering the drains and facilitate waste removal. Additional drains may have to be considered. CASE HISTORY NO. 1898 Hexane Fire/Explosion Description: A chemical operator had prepared a 2,000 gallon Pfaudler vessel for atmospheric distillation of hexane from some mother liquor. Steam was turned on and as the temperature started to rise the operator noticed fumes seeping through this manhole cover. He attempted to tighten the cover. The shift foreman, on his plant rounds, noticed what was going on. Realizing a dangerous situation was in the making, he ordered evacuation of personnel in the area. The chemical operator turned off the steam to the vessel and left the building. The shift foreman closed the garage type door between buildings to minimize spread of the fumes, turned on cooling water to the vessel jacket and also left the building. Shortly thereafter an explosion took place. No one was injured. Some steam and water lines were broken, parts of two walls were knocked down, all windows in building were broken as well as windows in two buildings across the street and parts of the roof were separated from the building by the blast. There was considerable water damage to finished product. The temperature recorder for the involved vessel was destroyed but all vessels in building appeared to be intact. -91- CMA 048805 Cause: Investigation revealed: 1. Hexane fumes escaped from the vessel's manhole due to a defective gasket and inadequate clamping (three instead of six). The fumes came into contact with a source of ignition and the explosion resulted. 2. A centrifuge ventilation system was in operation at the time of the explosion. The cover for the blower was torn loose leading them to believe this area to be the ignition source. Tramp iron was found in the blower housing and it is uncertain whether the unit was driven by conducting belts. Either a struck spark or static electricity discharge could be the ignition source. Apparently the hexane fumes entered the centrifuge exhaust system, contacted an ignition source, exploded, and propagated throughout the building. Preventive Measures: 1. When clamping down manhole covers, a sufficient number of damps are now being used (six). 2. All gaskets are being inspected before using and being replaced more frequently than before the explosion. 3. Emergency shut-down procedures have been written into all plant processes. 4. AH drive belts purchased, even in non-hazardous areas, are to be of the conductive type. Our belt supplier has been notified of this. 5. The centrifugal blower unit in building will be re moved and replaced by an approved unit of nonferrous construction. CASE HISTORY NO. 1899 Paint Spray Gun Description: A painter was in the process of flushing "Airless" spray painting equipment with solvent to clean paint from system after completion of a paint job. The painter inadvertently brought his left index finger into close proximity with the spray gun nozzle while simultaneously operating the gun. The solvent under high pressure and velocity penetrated the skin and tissue to a depth probably exceeding one-half inch. The injured was taken to a Company physician who removed affected flesh and foreign material from the finger tip. Subsequent visits to the doctor resulted in removal of the outer layer of tissue on the distal phalange. No infection occurred and the doctor expects the finger to return to normal. Cause: Unsafe act -- failure to follow manufacturer's recommended instructions for flushing the equipment. Preventive Measures: 1. Employee Education -- review this injury at all safety meetings, emphasizing the hazards involved in using high velocity nozzles of all types. 2. Review manufacturer's operating instructions with those craftsmen who use the "Airless" spraying equipment, emphasizing the safety procedures con tained in the instructions. CASE HISTORY NO. 1900 Laboratory Distillation Description: An operator was removing a mixture of hexane and mineral spirits from a solution of amorphous p0[y. propylene in order to isolate the solvent-free amorphous polymer. Standard procedure calls for first distilling 0ff hexane from such solutions at atmospheric pressure Residual hexane in the sample and higher boiling solvent is then removed under vacuum using a vacuum pump. dry ice condenser is in line before the pump to knock out condensable vapor. The operator had stripped one such sam ple and was finishing a second sample. In order to break the vacuum and remove the sample, he vented the vacuum pump to the air at the manifold. He then reached down opened a cabinet door, and turned off the pump which was located in the storage cabinet under the laboratory bench. When he turned off the pump, a flash fire resulted which was quickly extinguished and the operator received only minor bums. Cause: The investigating committee concluded that the fire was the result of ignition of hexane vapors which had accumulated in the confined space of the cabinet where the vacuum pump was located. The source of ignition was probably a spark which occurred when the switch was thrown to stop the motor. Preventive Measures: 1. Vent vacuum pump exhausts to fume hoods with a positive draft fan. 2. Move electrical switches outside cabinets where vac uum pumps are located. CASE HISTORY NO. 1901 Acid Sprays into Employee's Eyes Description: The normal lines to an acid "batch" tank were plugged. The decision was made to use a flexible hose to transfer the acid from the main supply line to an alternate "batch" tank. A high pressure flexible hose was connected downstream of the acid meter on the main supply line. The other end of the hose had a 90 elbow and a half union on it (from a previous job). The end of the hose was left hanging into the alternate "batch" tank through a 4" x 4" opening. Approximately 20 gals, of acid was metered into the tank, which had 25 gals, of water already in it. Upon comple tion of the transfer, the operator proceeded to flush the hose with a small amount of styrene, using the regular sty rene pump and lines that were manifolded into the acid line for this purpose. The operator opened the valve on the styrene line into the acid system. He then asked a second employee to open the styrene valve at the meter and start the pump. The operator held the hose approximately 4 feet from where the loose end entered the batching tank. He twisted the hose, attempting to direct the flow down and against the inside wall of the tank. Almost immediately the hose whipped and the loose end flew out of the tank, spraying the operator. -92- CMA 048806 ^Jhe operator was wearing monogoggles and safety glasses sideshields so the force of the flow did not hit his directly. However, acid splashed under his mono- eoggles and up into his eyes. The second employee reacted quickly to shut off the pump and valve. The operator rushed to a nearby eyewash fountain. He washed his eyes thor oughly for 15 minutes and stripped out of his clothes. The second employee turned a water hose on him to wash off other exposed areas. The operator was hospitalized with acid bums on his upper torso, face and eyes. Cauie: Temporary piping, inadequately secured, was being used because the lines were plugged on the permanent facilities. Preventive Measures' 1. Repipe batching tank to improve line drainage and to avoid consequent polymerization. 2. Use electric tracing to upgrade the acid system to provide better temperature control. This will prevent freezing and polymerization. 3. Review all chemical and physical properties of ma terials handled, and update operating and handling procedures. Spell out the protective equipment required. 4. The use of open-ended hoses for handling hazardous materials will not be permitted without the end being firmly anchored or restrained. CASE HISTORY NO. 1902 Boxcar Loading Description: Two employees had loaded one section of rail road boxcar with baler twine at the rail siding of building. The buyer had specified in the shipping instructions that the material be braced with bulkheads in each end of the car. The car was equipped with two sliding bulkheads stored in one end of the car. One employee went to move one of the bulkheads and did not notice that the rail which permits the bulkhead to be moved was detached and located in the opposite end of the car. He released the locking pin and the bulkhead (weight approximately 2,000 pounds) tilted toward him. He momentarily placed his hand against the bulkhead to stop it from tilting; however, realizing he could not stop it he ran to escape the falling bulkhead. Cause: 1. Direct -- Four, 1/2 inch by 2 inch bolts had been sheared which caused the bulkhead swivel and sup porting rail to become detached. 2, Contributory -- The bulkhead was not supported when the locking pins were released by the pin handle. Preventive Measures: 1. Since these bulkhead cars are no advantage with cer tain products this Division will not use bulkhead equipment unless specified by the buyer. . When buyers specify bulkhead equipment to be used, a detailed inspection of the bulkheads will be per formed by the materials handling foreman before the bulkhead is used. CASE HISTORY NO. 1903 Toxic Exposure -- Delayed Medical Treatment Description: On Sunday, an operator inhaled NO* fumes which escaped from the copper dissolver manhole. He attempted to operate the hoist to remove the copper basket from the dissolver but fumes were too great. He left the area, donned a Chemox Mask and returned to remove the basket. He did not have his mask positioned properly and again had to leave the area. He adjusted the Chemox face piece and returned for the third time and succeeded in remov ing the basket. Once this was done the fumes subsided. The incident went unreported until the injured employee called in sick on Monday (Labor Day). When the illness was reported there was reluctance on the part of the substitute physician to admit the employee to the hospital. Preventive Measures: 1. When fumeovers occurred, they usually went unreported since the basket was removed promptly and without benefit of the Chemox Mask. Obviously operators were not familiar with symptoms and effects of NO* inhalation. This information will be stated in the written operating procedure and made a part of the verbal instructions. All operators will be instructed in these hazards and necessity for prompt reporting of all injuries. 2. Adequate medical attention was delayed due to the Labor Day weekend. Contact has been made with the plant doctors to correct this situation. 3. Improvements on exhaust system will be made. 4. Employees will be retrained periodically on proper use of Chemox Masks. CASE HISTORY NO. 1904 Valve Placement -- Filter Failure Description: A chemical operator was pumping sodium hyd roxide into a makeup tank through a filter and a meter. The sodium hydroxide was being pumped from a storage tank about one block away. Pump pressure at the storage tank is 50 pounds maximum. The filter is rated at 200 pounds. When the operator shut off the pump, the gasket displaced on the filter and caustic sprayed behind his safety glass into both eyes. He groped for the eye wash fountain, about ten feet away, and yelled for help. With help, he flushed his eyes for 10-15 minutes until he could be taken to the dispensary. He suffered caustic bums of his face and both eyes, the right eye being more serious. The doctor stated that without the continuous flushing with water, it would have been more serious. Cause: The filter and meter was a new installation and this was the first time that it was used. An automatic shut-off valve was located at the tank side of the filter and meter which closes when the pump stop button is pushed. It is assumed that the instantaneous valve shut-off caused pres sure in the filter to build up immediately from practically zero to 50 pounds. Since the filter was rated at 200 pounds pressure, it is possible that the filter gasket was wrinkled on installation and/or was not tightly in place. -93- CMK 048807 Preventive Measures: 1. That filter/meter installations be pressure tested before they are put into operation. If advisable, due to corro sive material, wear full protective equipment. 2. Change location of automatic shut-off valve to pump side of filter/meter assembly. This will avoid sudden surge of pressure in the filter or meter. READER'S COMMENT "We experienced a similar accident. Subsequently, as an additional preventive measure, a circular splash shield has been installed on the filter so that a leak which might occur from a failure of a gasket would be directed down the walls of the filter rather than in all directions, endanger ing other persons passing by.'' CASE HISTORY NO. 1905 Acetic Anhydride Description: A chemical operator suffered severe irritation of both eyes from exposure to acetic anhydride fumes. He was wearing splash goggles and a Gasfoe respirator while searching down the source of the leak. The source was an open end line behind a Pfaudler drier which was fed by an open valve at a "T" connection on the mother liquor line. When the valve was closed the leak stopped. Causes: 1. General misunderstanding among foremen and operators that splash goggles provide fume protection tor eyes. 2. Conditioning of all plant personnel to the point where they accepted a certain level of acetic anhydride fumes as pan of the job. 3. Lack of understanding that acetic anhydride fumes can cause delayed eye irritation and bums. 4. Failure to blank unused lines during final hook-up phase ot the start-up of a new process. 5. Failure to check process lines for open valves. Preventive Measures: 1. Training personnel in: A. Correct use of splash tight goggles with special emphasis on restriction of use as eye protection from fumes. B. Correct methods for checking that proper valves are opened or closed and lines are connected before materials are pumped, every time it is pumped. C. Developing a questioning attitude in the minds of each operator about unusual conditions such as fumes, odors, noises, etc. -- No matter how slight they are. Stop accepting fumes as part of the job, 2. Review' all lines and equipment to insure that no hazardous conditions exist due to improper shut downs or hook-ups and then provide proper pro cedures to prevent these conditions from occurring. 3. Establish firm Guidelines on the uses of Gasfoe respirators, canister masks, air line masks and airpaks. CASE HISTORY NO. 1906 Pressure Testing Description: An operator was disabled when he breathed toxic vapors from escaping acrylonitrile. The suspension kettle in a unit had been out of service for 24 hours to allow repairs to a leaking gland on the agitator and clean out of the process lines from the kettle, up to and including the condenser (see attached diagram). Repairs were com pleted and the kettle was charged with water, heated to 85C., and pressurized with nitrogen to 7 kg./cm2, in order to check for leaks. Pressure was maintained on the kettle for just over two hours, and as there was no significant drop over this period, as noted on the panel recorder, it was assumed that the system was leak free. The panel operator then vented the kettle through valve F and prepared to charge the water phase from the distillate receiver. This is achieved by "blowing" with nitrogen pres sure with valves E, B, and C closed. On opening valve A to admit the nitrogen, a loud "whistling" noise was heard in the control room. The chief operator went into the plant to investigate, and returned shortly afterwards hav ing found a large gas leak on the flange above valve C, He then shut off the nitrogen (valve A), opened the vent (valve B), and after five minutes, returned to the plant with a mechanic to indicate what was required to repair the leak. On again returning to the control room he began to feel dizzy, was sick and showed typical signs of acrylonitrile poisoning. Two supervisors who had been in the plant at the time of the "whistling" had now also gone to the control room, and on finding the injured, administered amyl nitrite capsules and called an ambulance. The ambulance arrived and transferred him to the hospital for observation, Investigation: 1. During the time of the repair work on the suspension kettle, the distillate receiver contained a two-phase mixture of monomer (top) and water (bottom). Both these layers contain appreciable quantities of acrylo nitrile. 2. For process reasons, control valve D is fitted with a "stop" to prevent complete closure. 3. The procedure for pressure testing the system, as incorporated in the operating instructions, states that the manual by-pass valve E must be open during the test, so that the condenser and the distillate receiver are also pressurized. 4. On breaking the leaking flange after the incident, the gasket, a conventional asbestos type, was found to be cracked, 5. While the injured was in the control room awaiting the ambulance, the first-aid center was called to bring an oxygen supply to the plant. Some confusion resulted in that it was not known if such a portable system was available, how it could be transported, and whether oxygen should be administered. Oxygen was eventually given by the ambulance personnel. Conclusions: The actual way in which the acrylonitrile va pors escaped is concluded to be due to the nitrogen flow passing into the distillate receiver, entraining the volatile AN vapor, passing through the condenser, through valve D and then out through the leaking flange. -94 CMA 048808 T There are two possibilities as to when the failure of the et occurred: If the pressure test was correctly carried out with valve E, open, it must be assumed that the flange was capable of holding 7 kg/cm2 pressure for the two hours of the pressure test, and that the failure coincided exactly w ith the repressunzation of the dis tillate receiser. 2. If calve E was closed during the pressure test, as valves C' and G were also closed, the test would only be on the suspension kettle itself and would not include the condenser, distillate receiver, or the flange m question. This would mean that pressurizing the distillate receiver to charge the suspension kettle would give the first indication of a leak on the flange. The Committee considered case (2) the most likely sequence of events, and that the pressure test was incorrectly carried out. Cause: 1. Failure to follow procedure. 2. Incorrect operation: Procedure for leak-test on reactor system was not followed. 3. Contributing factor: Incorrect installation of gasket. Preventive Measures. 1. All operators to be retrained in procedure for pressuretesting reactor system and procedure to be strictly enforced. The hazards of AN to be reemphasized to all personnel working in the plant, including contractors. 3. Review suitability of gaskets used on reactor pressure system. 4. Review need for emergency oxygen supply in the control room, or easily portable system in first-aid center with suitable transport. 5. Investigate feasibility of installing AN detection sys tem in hazardous areas. 6. Re-train first-aid personnel in treatment of persons affected by acrylonitrile and other toxic materials. CASE HISTORY NO. 1907 Rotometer Explodes Description: A Pilot Plant Technician was in the process of starting air flow to a Jet-O-Mizer airmill. The air to the mill enters a globe valve by a 2" line with a rotometer downstream of the valve. This rotometer is used to calibrate the air flow to the mill. The line pressure is 100 psig. The calibrated tube in the meter is rated at 150 psi at 200F. As the air pressure was increased by means of the globe valve, the calibrated tube in the rotometer disintegrated, shattering the plastic shield over the tube. Particles of glass and plastic from the tube and shield were propelled into the face, mouth and hair of the operator. The operator was wearing safety glasses and did not receive any eye injury, but the lenses of the glasses were scratched. Possible Cause: After investigation of this accident, it was determined that the air probably was increased too rapidly and the measuring float in the rotometer probably became wedged in the tube and was suddenly released with the increase of air pressure, causing the "float" to slam into the side of the glass and thereby causing the tube to break -- as well as the plastic shield. Preventive Measure: A different type metering device will be used. Will discontinue using rotometers with glass meter ing tube to calibrate air flow. CASE HISTORY NO. 1908 Aniline Exposure Description: On the evening shift, a chemical operator absorbed sufficient aniline from a drum spill to be hos pitalized due to a critical level of methemoglobin in his blood. The operator was righting some aniline drums that had fallen from a pallet. One of the drums leaked onto his trousers. He wiped the affected area with hot water and a soapy towel and changed clothes after the incident but did not shower. Within three hours of the exposure, he reported to his foreman in a weakened condition and with symptoms of methemoglobinemia. Upon recovery, the operator related the dangers of aniline and the safety practices he had been schooled in, but indicated that at the time of exposure he felt the lesser procedure he followed was enough. Cause: The prime cause of the disabling injury was the failure of personnel to follow prescribed safety procedures even though they had been thoroughly covered in safety meetings. Preventive Measures: 1. Eliminate clamp top metal drums on in-plant aniline service. 2. The training education program on aniline handling and treatment of aniline spills will be reviewed, aimed at making it more effective. Included will be closer enforcement of safety rules backed by disciplinaryaction if needed. -95- CMA. 048809 3. The accident showed a potential problem in the area of medical attention. Although the plant physician had established medical procedures at the hospital, methemoglobinemia is not easily diagnosed unless in the absence of the plant physician, emergency room personnel are alerted at the time of the incident. A packet has been prepared to accompany the patient and will include medicines, information alerting the doctor, and \\mptom and treatment data. CASE HISTORY NO. 1909 Lock-out Failure Description: A chemical lead operator was preparing to load a pancake dryer when he noticed the unloading door was open. When he went to close this door he noticed some fibrous dirt in the door track and swiped at it with the back of his gloved hand. The power was on in the sweep agitator. The clean-out bar struck his left index finger mashing it against the door track, gouging out flesh from the palmar surface as it bounded off. He stated that he had forgotten he had turned on the power about fifteen minutes prior to the injury. This is a quiet piece of equip ment. Employee lost five days from work and will have to have plastic surgery performed to improve function of the finger. Kause: Employee failed to lock-out the power to this equip ment before cleaning dirt from the door track. Preventive Measures: 1. Signs were put on the dryer "lock-out before putting hands in this dryer," 2. All employees were told the facts of this accident and instructed in lock-out procedures. 3. A log is being kept on lock-outs to determine if pro cedures are being followed. CASE HISTORY NO. 1910 Gas Inhalation Description: An operator suffered throat and lung irritation from inhalation of sulfur dioxide gas when a loaderman mistakenly pumped liquid sulfur dioxide through a bypass valve into the vent system. Cause: Loaderman failed to follow correct procedure, al though he was experienced and had been properly instructed. preventive Measures: . Correct procedure has been reviewed with employee and potential seriousness of his error explained. 2. Plans are being made to develop a more foolproof loading system for liquid sulfur dioxide. CASE HISTORY NO. 1911 Reaction Explosion Description. A chemical reaction of an aromatic amine with a chioro nitro compound went out of control due to ferric chloride catalyzed side reactions when the reaction mass became acidic. Natural soda ash used as an add acceptor in the non-aqueous system was ineffective. The exothermic side reactions developed pressures above those normalK encountered in the process. A weakness in the manhole closure caused the cover to blow off despite operation of a 60 lb. relief valve on the 100 psi designed reactor. Thrust of gases from the open manhole propelled the vessel down ward, releasing gases to the building where a combustion explosion took place. Six employees were burned in varying degree, one later died. Venting through large window areas of the building limited the amount of structural damage. Damage included non-production areas separated from the process section by a wall not sufficiently strong to withstand explosion forces. Many sprinklers operated and fires were quickly brought under control. Cause: Natural soda ash was used in this batch as an acid acceptor instead of synthetic material which had been used successfully for over 20 years. In the non-aqueous medium the difference tn ciystaiinity made the natural soda ash less effective than the synthetic type normally used: hence it acted like an undercharge of soda ash. This permitted an acid buildup which formed ferric chloride as the reactor was steel. Iron oxides were also present. Laboratory work verified the plant experience. However, regardless of soda ash type no significant side reactions could be demonstrated if iron was absent. Confinement tests indicate the side reactions could develop pressure of 400 to 600 psi. Preventive Measures: 1. Use of cry stalme natural soda ash should be reviewed in non-aqueous reactions for possible reduced activity compared to synthetic grades of soda ash. 2. More hazard evaluation on potentially hazardous pro cesses with emphasis on possible side reactions induced by probable contaminants. 3. Check for weakness in reactor system when hazard evaluation tests show that potential pressure may exceed design pressure of reactor components. 4. Fire and explosion resistant wall to separate hazardous process area from non-production facilities. CASE HISTORY NO. 1912 The LOCATION of the Safety Valve is Also Very Important Description: A 3000 gallon aluminum tank was being used for 56Vc acetic acid service. It was pressurized with 6 pounds of air to force it through overhead lines to the dis pensing locations inside the building. The Safety Valve was located on an elbow right next to pipe tee with a vertical riser of about 6 feet. The moisture trap was on the horizontal line. -96- CMA 048810 The scale, dirt, and moisture from the vertical pipe and mte horizontal run was driven into the elbow and the Safety lve opening each time the system was pressurized. Finally e elbow and valve became plugged so that when the Reduc ing Valve leaked, the Safety Valve could not function. One head was blown out of the tank with enough force to remove 1000 square feet of window, a portion of the roof, and the brick chimney of the adjacent building. For tunately the injuries were minor but the property damage was extensive. Preventive Measure: A Safety Valve should be located to minimize the amount of foreign material that can accumulate in its fitting or entrance. In this case it could have been off a tee in the vertical riser, or at the top of the riser. Such valves should be removed and the valve and fittings checked on a periodic basis. 0M i-rv CASE HISTORY NO. 1913 Drum Explosion Description: An explosion occurred in a 55 gallon steel drum, causing the bottom to be blown off and rocketing the drum up 18 feet, penetrating through a 5/8 inch plaster board ceiling and a 1/2 inch plywood roof and damaging a 2" x 10" joist on the way through. The drum had contained 2.5 gallons of 50% caustic and 10 gallons of methanol. Two gallons of chloroform had just been added to the drum to deactivate any possible traces of a toxic material in the chloroform. A hissing noise was heard and the funnel in the open bung hole was blown out. The technicians, wearing air flow hoods and dacron coveralls, quickly backed away and were not injured as the drum "rocketed up". Cause: NFPA's Manual of Flazardous Chemical Reactions, 491M-15, checked after the explosion, clearly states that when chloroform is added to methanolic sodium hydroxide, a vigorous exothermic reaction occurs. This reaction is well documented in MCA Case History No. 498 when the same reaction caused a drum to explode. Preventive Measures: The decontamination protocol has been modified so this procedure is not repeated. The incident was used to emphasize that when new procedures are being established, the literature should be checked prior to start-up, not after an accident. In this case, the decontamination procedure was agreed upon at a committee meeting with people hav ing many years of diversified chemical experience and only points out that in untried areas, nothing can be taken for granted. 3. Procedures for handling waste solvents are being reviewed. CASE HISTORY NO. 1914 Di-tert-butyl peroxide Di-tert-butyl peroxide is one of the most stable initiators in industrial use. Periodically it has been prepared by the addition of tert-butyl alcohol to a mixture of hydrogen perox ide and sulfuric acid. (A 2-to-l weight ratio of 789f sulfuric acid to 509f H2O2 has been the most popular combination.) Although the addition of an organic compound to excess hydrogen peroxide is always questionable, this procedure on a small scale can give excellent yields with apparent safety. But the procedure is dangerously deceptive. In the initial stages of alcohol addition, the tert-butanol reacts w ith the hydrogen peroxide to form tert-butyl hydroperoxide. This reaction is moderately exothermic, and if there is not enough cooling available to handle the heat, decomposition of the rest of the hydrogen peroxide (and/or peroxysulfuric acid) can occur with explosive force, with the tert-butyl hydroperoxide itself functioning as an initiator or catalyst. In such cases, there will be a gradual (and not too alarming) temperature increase, and then the whole mass will simply erupt out of the reactor. This danger is most acute only during the early stages of the reaction. As the hydrogen peroxide content drops and the water formed dilutes the system, the danger of an explosion decreases, and in the latter stages (when all the H2O2 has been consumed) the process is probably as safe as any organic peroxide synthesis. In the laboratory, where small quantities are used and cooling is usually excel lent, an explosion may never be seen. In the plant, the danger is severe. At least nine people have been killed in four plant explosions during the attempted commercializa tion of this process. It should be noted that this danger was not uncovered in the usual scale-up studies. Excerpted from a letter by Thomas A. Schenach -- C&EN, Feb. 5, 1973 -- Page 39 CASE HISTORY NO. 1915 o-Nitrobenzoyl Chloride Explosion Description: A violent explosion in the laboratory occurred when a chemist attempted to distill crude o-nitrobenzoyl chloride, prepared by reacting o-nitrobenzoic acid (1.20 mole) with thionyl chloride in refluxing benzene. For tunately, the distillation was carried out in a hood with the safety window pulled down and no injuries occurred. The distillation was carried out in the presence of phosphorus pentachloride, as advised in the literature (Beilstein's Handbuch 9, Suppl. II, pp. 245-246). The detonation occurred at the boiling point (128 and 1 mm pressure) after 10-20 --97- CMA 048811 ml of o-nitrobenzoyl chloride had been collected. The proce dure had been used previously on a 0.50 mole scale (bp 94-95 at 0.025 mm) with no untow-ard results. Other researchers have reported the successful distillation of small quantities of o-nitrobenzoyl chloride but experi enced a v iolent detonation when the purification of an 8-mole run was attempted by vacuum distillation (W.A. Bonner and Charles D Hurd, ./. Amer. Chan. Soc.. 68, 344-5 (1946) ). According to Bonner and Hurd, reasonably pure o-nitrobenzoyl chloride is obtained b> the reaction of o-nitrobenzotc acid and thionyl chloride in refluxing benzene. On a 1.2-mole scale, we experienced no difficulty in removing benzene, excess thionyl chloride, and gaseous byproducts iHCl and SCE) on a rotary evaporator at 30-40, leaving a mixture of a liquid and a solid. The solid could presumably be removed by filtration. It is conceivable that, should further purification be desired, low-temperature crystalliza tion (o-nitrobenzoyl chloride melts at 25) could be carried out at this point. CASE HISTORY NO. 1916 Hydrogen Gas Exposure Description: A research and development chemist attempted to bleed a laboratory hydrogenator operating at 1,000 pounds. The bleed line was plugged and the reactor did not vent. During the course of attempting to open the line, the plug suddenly released while the chemist's hand was at the mouth of the bleed line. The sudden release at high pressure inflated the chemist's right arm with hydrogen gas. He was hospitalized five days then he remained at home until the hydrogen completely diffused. CASE HISTORY NO. 1917 Pressure Build-Up in Vented Line Description: In preparation for draining pressurized hot melt glue pot, employee followed depressurizing and venting procedures prior to removing the lid. When the pressure gauge went to "zero", he cracked the melt-pot cover and was sprayed on the hands with hot glue. He was not wearing gloves as prescribed by plant safety rules. Cause: Improper setting of rheostat resulted in elevated glue temperature which may have caused some pressure build-up after venting. Preventive Measures: Equipment is being installed to assure positive temperature identification and depressurization; and improved personnel protection is being specified. CASE HISTORY NO. 1918 Portable Press Description: Three employees were moving a portable 18 inch rubber covered filter press. The injured employee was in front, walking backwards and guiding the press. Two other employees were pushing the press in a line parallel to its length with the hydraulic ram end leading. When the two leading wheels hit an expansion joint in the floor the leading legs snapped off. The leading end of the press collapsed trapping employee's right foot under the piate tightening w'heel. Immediately upon this impact the trailing legs snapped off and the entire press crashed to the floor releasing injured's foot. Employee suffered severe crushing of the first three toes and less severe injury to the other two toes. It became necessary to amputate the big toe and the toe next to it. Causes: 1. The short, narrow-base, cast iron legs and the high center of gravity of this, or nearly any filter press, make them totally unsuited for mounting on wheels and rolling around. 2. The wheels and mounts for them raised the press another 15Vi in. off the floor and extended the lever action of the legs that much more from the point where they join the body of the press. 3. Cast iron is designed to take compression, not tension. When this press was rolled across the floor the legs were under tension. Preventive Measures: A. Remove wheels, fabricate new steel legs, extend base out each side for a wider base support and brace one side from the front to the back legs to stop any sideway motion on the legs. B. Cover the expansion joint at the scene of the accident with a beveled steel plate anchored to the floor and examine other joints in the floor for similar wear. C. Repair all floors in the plant, recognizing that there are many other potential accident areas because of it. D. Recognize the hazards involved in all portable equip ment and redesign them for safe operation. Other Information: A close examination of the safety shoes that employee wore revealed that if he had not had the steel toe to protect his foot there is a good possibility that his toes might have been sheared off instantly. It was con cluded that the safety shoes did lessen the injury substan tially. CASE HISTORY NO. 1919 Accident During the Collection of Waste Chromic Acid Solution Description: The following incident occurred when a tank truck owned by a waste disposal company arrived to collect a quantity of waste chromic acid plating solution. The solu tion contained 22% sulphuric acid and 400 grams per liter of chromium. The truck was fitted with a Fiberglas tank lined with polypropylene and the procedure was to use a vacuum pump attached to the vehicle to withdraw the w aste solution into the tank. After about 100 gallons of the solution had been drawn into the tank truck, the safety valve blew and vapors appeared around the seal of the rear door of the tank. The force of the explosion was sufficient to spray the inside of the --98-- CMA 048812 plating shop due to back pressure through the suction hose. JBvge areas of the surrounding roadway were covered with ^h solution. Two employees in the area received superficial bums. Pollution was kept to a minimum by diverting all effluent from the area to a nearby holding basin where it was subsequently diluted and released into the local sewer system at a controlled rate which was chemically monitored. Cause: The violence of the explosion made it impossible to collect meaningful samples to determine the cause of the violent reaction. The collecting contractor claimed that the tank truck had collected a similar solution from another site on a previous day and that the tank had subsequently been flushed out. It can only be concluded that some contam inant -- most probably a reducing agent -- was already present in the tank or hose connection and reacted with the strongly oxidizing chromic acid to yield the violent reac tion. Preventive Measures: The following precautions have been recommended to avoid a recurrence of the incident: 1. Future collections must be made from a holding tank installed outside the plating shop; the solution must be diluted when it is transferred to the holding tank. 2. The tank truck must be flushed out immediately prior to collection -- this is to be supervised by the waste contractor's chemist. 3. The contractor will be given three working day's notice prior to making the collection and will be pro vided an analysis of the solution to be picked up. . Collection will be supervised and strict measures taken to insure that only personnel who are directly involved in the operation, and who are wearing appropriate protective clothing, are allowed in the vicinity of the loading operation. 5. A supply of neutralizing chemicals have been made available in the immediate area with backup quantities on hand at the plant site. CASE HISTORY NO. 1920 Tank Car Hose Description: Second degree steam bums on ankle and foot occurred while disconnecting a hose to the drain line from a tank car. Cause: Employee had hooked up a steam hose with an adapter to a quick-opening coupling connected to the bottom valve of a tank car to clear the line of solidified material. When he was unsuccessful in clearing line, he shut off valves to the steam supply and the bottom of the tank car. After waiting several minutes, he proceeded to open the locking ears of the quick-opening coupling, when the hose blew off. Preventive Measures: 1. A bleed valve was installed after the steam supply valve so that the hose could be properly bled off before disconnecting. a. A survey was taken throughout the plant where steam hose stations are located. Bleed valves will be installed at the steam supply ends not now so equipped, to make certain the hoses are properly bled before dis connecting. 3. All employees were informed of the accident and instructed to bleed steam off at the new connection before disconnecting hose. READER'S COMMENT "The solution to the problem as published should not be by the use of bleed valves only, but should also discon tinue the use of quick-couplings on steam hose as they are apt to blow off and then the hazard is much greater. We would suggest a Boss type connection on any steam hose. Piping -- where practical -- should be used because pipe is much safer than hose." CASE HISTORY NO. 1921 Moving Equipment Description: While operating electric work saver, injured was struck in the back by a lifting device mounted on another electric work saver, forcing injured's chest against steer ing/operating handle resulting in serious injury. Cause: Injured employee was walking backward moving an electric walk-along transporter to align it into position to guide it under a skid and a ride-on vacuum lift truck was moving in the same direction several yards ahead. The ride-on vacuum lift truck stopped to allow a ride-on fork-type truck moving toward it to make a turn, and to permit more room for this turn, the vacuum lift truck backed up resulting in the injured employee being caught between the handle of the truck he was moving and the vacuum cups of the vacuum lift truck. He suffered five broken ribs, a fractured sternum and internal bleeding. Preventive Measures: A request will be made to install a mechanical or bell-type sound on all vehicles that will sound whenever a vehicle is put into motion. As an interim measure, existing electrical and manual horns will be sounded prior to making a move with a ride-on unit. Rear view mirrors will be installed where practical on all ride-on type transporters. All department personnel have been reviewed on allowing proper distance between vehicles and to check traffic conditions before changing direction. CASE HISTORY NO. 1922 Crane Operation Description: A pipefitter and his leadman were in the process of replacing two sections of 4" pipe from the piperack. With the proper scaffolding provided they had removed all of the bolts except one from the connecting 4" flange which was 9 feet above ground. A 12Vi ton, telescoping boom Pettybone crane was positioned to secure and remove the pipe. The pipefitter moved from the scaffold to the top of the multi-pipe rack to install the sling to the crane load line hook. He removed the last bolt, pushed the flange away and the boom and section of 4" pipe dipped exces sively when the load was imposed on the crane load line. He thought the crane was going to tip over and he jumped to the ground breaking the heel bone of his right foot. -99- CMA 048813 Cause: The improper positioning of the crane; the dog above the back axle was in the up position, the front outrigger was not set flat on the ground and the rear outrigger was not down or resting on anything. The job was completed without further incident using the same crane in the same position but with the dog and outriggers properly positioned. Prevent!i e Measures: 1 The responsibilities of the crane operators will be reviewed in detail with them. 2 The incident will be fully discussed with all operating engineers. CASE HISTORY NO. 1923 Machine Guard Removed Description: During the first shift, an employee was operat ing #33 injection molding machine and noticed that machine #32 at his back was having trouble as the pieces were sticking in the cavity. The shift area foreman was setting his machine up and without consulting him. the employee tried to remove the stock part from the back of the machine, where the foreman could not see him. At the moment he was attempting to remove the pieces, the foreman made a quick closing-opening operation of the press to remove the pieces by means of the mechanical-injec tor system stripper type mold. The employee's right hand was inside the mold when the press was closed -- resulting in amputations of the distal phalanxes of the index finger. Cause: 1. Unsafe act of the injured employee. 2. Lack of lock-out procedure. 3. Lack of protection system for shutting off the machine when the back guard is removed. Preventive Mensures 1. Re-instruct personnel that removal of the protective guard from a machine is forbidden. 2. Install a protection system in the back guards of machines which will operate as a shut-off if the back guard is removed. 3. Prepare and establish a lock procedure. 4 Prepare and establish a procedure and also a check list for reviewing machine protection systems. other points. The duct extended through an upper floo and through the roof. r Investigation showed that a bolt from the wiper blade on the rotary valve came loose and was propelled through the mill. The bolt made several revolutions before tearinp and passing through the screen. The mill speed is 6200 rpm. Cause: Although the mill is stainless steel, sparking cannot be eliminated as the source of ignition. Preventive Measures: 1. The bolts on the wiper blade were retightened and the nuts spot welded. 2. Safeguards at all ribbon blenders are being studied as a result of this incident. Explosions in ribbon blen ders are rare occurrences. CASE HISTORY NO. 1925 Moving Equipment Description: The operator's right foot was caught between the door flange of the baler and the floor. He suffered amputation of the distal and middle phalange of the fourth toe on the right foot and a laceration to the third toe requiring two sutures. Cause: The injured had activated the switch that opens the baler door and immediately stepped over to the baler to unload the contents of the yam buggy. He was unaware that his foot was in the path of the baler door that was continuing to move below floor level, thus resulting in the amputation. Preventive Measures: 1. Modifications were made to the baler door eliminating the flange. 2. Dual pressure switches that operate the baler door were installed. 3. Signs were posted within the operating area to alert operators of the pinch point. 4. Revisions were made to the safety procedures to pro hibit the operation of the door if employees are on the platform. 5. Another method of disposing of off-grade yarn will be investigated by Engineering. CASE HISTORY NO. 1924 Explosion in Ribbon Blender Description: An explosion occurred in a ribbon blender resulting in damage to the explosion venting duct work but no other damage and no injuries. Niacin was being fed automatically from the feed hopper through a rotary valve into a mill, which discharged verti cally to the blender, when the explosion occurred. The blen der top and sides had been stiffened because test results revealed that niacin can develop high explosion pressures under ideal conditions. The large sheet metal vent duct also was stiffened with steel angle iron at the joints and CASE HISTORY NO. 1926 Fork Lift Accident Description: A semi-trailer pulled away from the loading dock at the same time a fork lift was entering the trailer. The lift truck fell approximately 4 feet to the concrete apron in a backward position with the forks and load resting on the back of the trailer (see attached photograph). The fork lift driver remained in the seat and was not injured. Three lift truck drivers were involved with the loading. "A" driver started the loading of the trailer and after com pleting only a portion, turned the assignment over to "B" -100- GMA 048814 1 driver. "B" driver continued to load the trailer, while "A" ^taver and the truck driver went to handle the bills of lading, driver exchanged fork lifts with 'B" driver, as he dad borrowed his fork lift. "B" driver had trouble locating the balance of the load. At that time "A" driver and the truck driver had completed the paper work and the truck driver removed the chocks and boarded his tractor. Since the last pallet was on dnver'sfork lift he was requested to place it in the trailer. As "C" driver started to enter the trailer, it pulled avvav from the dock. Prevent!i e Measures 1. Onlv one driver will be assigned to load a trailer. He will be responsible for installing and removing the chocks and releasing the trailer with the bills of lading. 2. This incident was discussed with all lift truck drivers. 3. Appropriate disciplinary action was given to "A" driver. A field engineer was called in to check the equipment and assist in the investigation. When asked his opinion as to the cause of the accident, his reply was that some pressure must have been on the vessel when it was opened. However, he stated that had pressure been on the vessel, then the safety lock could not have been opened. Another trial run was then made with a small amount of pressure on the vessel and the safety lock could be opened. The safety lock could also be opened with the circulating pump running. The pressure switch controlling the safety lock was checked and found to be inoperative. CASE HISTORY NO. 1927 chanical Interlock Failure Description: A laboratory technician was in the process of carrying out a routine work assignment to preheat water in a package and stock dyeing machine and, once the water was at the desired temperature, to load the machine with fiber for dyeing the following work day. At approximately 3:15 P.M. the water was at the desired temperature and he began to ready the machine for loading. When he opened the lid of the machine, a quantity of hot water came out and onto the employee. He w-as painfully burned and taken to the hospital w here he was admitted for treatment of second degree burns over approximately 659r of his body. Cause: Investigation by members of the Accident Prevention Committee, the Safety Department, Supervision, and a field engineer revealed the following. On the day of the accident, the technician had filled the machine and heated the water in the standard manner. When the water reached the desired temperature (200F), he moved to a control panel and turned off the circulating pump, opened the safety lock on the kettle lid, and opened the valve to drain water down to a point below the level of the domed lid of the kettle. He did not turn off the steam to the heat exchanger which heats the water in the kettle. At this point he walked over to the kettle, pulled on the handle to the lid locking collar, and the lid popped open enough to allow hot water to come out and bum him. Numerous attempts to duplicate the events which caused the accident were made but without positive, conclusive results as to what caused the water to surge out of the machine. All conceivable misoperations short of opening the lid with the circulating pump running were tried. This method of misoperation was not tried since the equipment was checked immediately after the accident and the pump was not running. As previously stated, the only abnormal condition found was that the steam was still on to the heat exchanger. Since the vessel could have been opened with some pres sure on it, the investigation then turned toward finding possi ble sources of pressure or other conditions which would force water out of the vessel and onto the operator. Two possible conditions were found. First, it was found that if the circulating pump is turned off, and the steam is left on, hot water will occasionally surge from two circulating ports 4" below the lip of the vessel. The other condition found is that water will be forced from these two ports if an airline used for drying fiber in the machine is partially open. The valve on this line was found to have a very loose stem nut and was very easy to operate. One final condition could have existed at the time of the accident and that was a partially plugged drain from the kettle. An experiment with cold water failed to cause water to surge out when the lid was opened. However, an experiment with hot water and a very slight amount of air bleeding into the vessel from the air line caused a considerable amount of hot water to surge out when the vessel lid was opened. Although the drain has worked per fectly during all experiments, this does not rule out that it was partially plugged with fiber at the time of the accident. One or more of the following conditions brought about the accident: 1. An inoperative pressure switch allowed the safety lock to be opened with some pressure on the vessel. 2. The steam was left on to the heat exchanger and just as the lid was opened, a surge of hot water came from the heat exchanger. -101- CMA 048815 3. A small quantity of plant air was bleeding into the vessel through a slightly open valve and pressurized the vessel. 4. The water level had not drained below the lip of the vessel due to a partially plugged drain. This condi tion would aggravate the results of either condition 2 or 3 above. Preventive Measures: 1. The defective pressure switch should be replaced with a non-mechanical switch. 2. The control console should be modified so that when the circulating pump switch is turned off. the steam to the heat exchange is also turned off. 3. Since the line supplying plant air to the vessel has no real operational value, the line should be removed. 4. A triple safety interlock system offered by the manu facturer should be acquired and installed. 5. Operational procedures should be revised so that the vessel's lid safety lock is checked each time the vessel is in use so that any possible malfunction will be detected. 6. Departments should review similar equipment to determine whether or not adequate safeguards exist. CASE HISTORY NO. 1928 Open Pan of Molten Resin at Floor Level Description: A momentary power failure in a resin handling area caused an abrupt shutdown of various process units and activated a large water sprinkler system. Coincident with the process shutdown, hot in-process resin material was diverted to open holding pans as a result of the shut down. A safety engineer entered the area to reset the sprinkler systems. By this time water was 6 to 8 inches deep in the area. Water was flowing out of the floor drains and also coming into the room from adjacent areas. The floor drain cover had been pushed off and the strainer was lifted out of the drain by the in-rushing water. The safety man stepped into this unprotected but hidden drain with his left foot and fell. As he fell, his left hand went into the pan of molten resin. He received second and third degree bums on his left hand and arm which resulted in 3 weeks lost time. Cause: The primary cause of this accident is the open pan of molten resin at floor level. Contributing causes are inade quate drainage for the sprinkler water system now in service and the control system which causes all the sprinklers to come on when there is a brief power dip. Preventive Measures: 1. The open pans of molten resin will be eliminated and a molten transfer system to a closed hopper sub stituted. Temporarily, the pans will be provided with removable lids. 2. An engineering study is underway to design a more efficient drainage system for removing sprinkler water. 3. Drain covers and strainers are being redesigned so that they lock in place on all floor drains. 4. A power backup system is being installed so that sprinklers will not be activated by a brief power dip CASE HISTORY NO. 1929 Ashing Fatty Tissue Description: A high school co-op had been assigned the job of filling three 25-ml Teflon-lined Parr bombs for the degradation of animal fat to inorganic constituents. She filled each bomb (in a dry ice-acetone bath) with 1 ml of fuming sulfuric acid and 1 ml of fuming nitric acid. About 0.5 grams wet weight of adipose (fat) tissue was added to bombs 2 and 3. The tops were screwed on. No heat was applied. The co-op then set the bombs on the lab desk. About ten minutes later, the co-op returned to the desk. At that moment bomb 2 exploded. A few seconds later bomb 3 exploded. The bottom of one bomb went through the desk and the Formica top shattered. The co-op went immediately to the safety shower. She suffered lacerations of the right hand, right upper lip, and the rear ear lobe. She also had an abrasion and swelling of the scalp over the right frontal skull area. Emergency treatment was given at the scene and she was taken to Medical and later to the hospital. It is believed all of her cuts were caused b\ the Formica, Cause: Subsequent calculations indicated that more than enough oxidizing material was present to completely oxidize the animal fat to gaseous products. Further, conditions were ideal for the formation of nitroglycerine and other nitrated organic materials. Under confined conditions, calculations show that the contents of the bomb could have reached temperatures as high as 4000K and pressures as high as 15,000 psi. The bombs are rated at 5000 psi and fail through the bottom in the manner observed. Preventive Measures: 1. Parr bombs will not be used for acid digestion ot predominately fatty materials. 2. When Parr bombs are used in experimental work, proper procedures and facilities should be established for their use including adequate explosion protection. 3. Review current methods for degradation of adipose tissue and set up appropriate safe procedures. 4. When inexperienced personnel initially perform experiments that may be hazardous, they should be thoroughly instructed in the proper procedures and should be observed by a competent supervisor the first few times that they run the experiment. CASE HISTORY NO. 1930 Acidizing with Hydrochloric Acid Description: A repairman was preparing to acidize a column containing iron sulfide scale with hydrochloric acid. After approval by the operating foreman and the issuance of a work permit, the mobile acidizing equipment was hooked up to the tower and circulation of acid began. The repairman climbed the seven foot ladder up the mobile tank to check the acid return line hose. He shouted to shut the pump j -102- CMA 048816 1 off and started down the ladder but fell from about the ur foot level to the ground. When first approached by Ihers in the area, he was unconscious; however, he was conscious within about one minute. He sustained no injuries. C mise 1 Acidizing equipment containing sulphur compounds. 2. Inhalation of hydrogen sulfide gas generated by the acidi7ins2 Preventive Measure*: 1 Existing procedures were re-emphasized that acidiz ing with hydrochloric acid is for carbonate scale only. 2. Special requests from the operating supervision is required to initiate acidizing any except carbonate scale. 3. Job safety analysis will be applied to all acidizing jobs. CASE HISTORY NO. 1931 Oxygen System -- Flash Fire Description: Employee received flash bums to his hand and chest when he opened a needle valve to an oxygen manifold system. The valve had been newly installed, and employee did not know it contained hydrocarbon oil lubri cant in the stem and packing area. Apparently the oxygen 2,000 pounds pressure ignited the lubricant and the valve led in a cutting torch effect. The 80% polyester-20% cotton shirt he was wearing ignited and could have been a contributing factor in the severity of the bums. Cause: 1, Lack of awareness of the extreme precautions that must be taken around oxygen system to assure safe operation. 2. Failure to investigate standards, procedures, and other sources to assure safe fabrication, installation, and operation. Preventive Measures: 1. Education and emphasis to assure that all employees know of the hazards involved in oxygen installations. 2. Some other means of heating the switches will be devised. 3 Special newsletter and flyer published to communicate details of incident. 4. Guidelines for the location safety manual will be developed to specify appropriate selection, use, cleaning, and maintenance of all equipment to be used in oxygen service. CASE HISTORY NO. 1932 Release of Flammable Gas ^^cri/wwr A reactor was charged with 250 gallons of vinyl chloride with the bottom valve and sewer valve open. Although a serious hazard was created by this release, no one was injured and no equipment was damaged. A helper was working with the mechanical cleaner operator to prepare #2 and #3 reactors for charging. It is part of his job to close the bottom and sewer valves. The helper related that he normally waits until a pun reactors are cleaned before closing the bottom valves. in this instance, he closed the valves on #2 reactor ,\ sl the mechanical cleaner was still running in #3 reactc' this time he put the initial charge water in #2 reacto' .me then proceeded to other work while waiting for #3 reactor Upon returning later, he thought he had closed the bottom valves on #3 reactor the same time he closed the valves on #2 reactor, so he proceeded to add the initial charge water. The charging operator stated that prior to charging reactors #2 and #3 he checked and tagged the bottom valves on #2 reactor and saw the valves open on #3 reactor. Later he proceeded with the charging of #2 reactor and noted the helper putting water into #3 reactor. He then proceeded with the charging of #3 reactor, at which time the gas release occurred. Cause: The specific cause of this accident lies in the failure of the helper to close the bottom valves on #3 reactor and the failure of the charging operator to check and tag the bottom valves prior to charging. Preventive Measures: 1. Appropriate disciplinary action was given both the helper and the charge operator for not following operating procedures. 2. This accident was reviewed in all departmental safety meetings. CASE HISTORY NO. 1933 Static Spark Ignites Methanol-Acetone Mixture Description: A chemical operator suffered first and second degree burns of the face, arms and chest when a methanolacetone mixture was ignited by a static spark. At the time the operator was trying to push some crystals into a centri fuge drop line at the bottom of a crystallizer using a non-conductive Teflon rod, when the vapors ignited and caught him as he stood over the manhole. The injured was admitted to the hospital and his lost time is estimated at 47 days. Preventive. Measures: There are obvious lessons to be learned from this incident. 1. The man was wearing a sweater of synthetic material which ignited, melted, and contributed to his bums, and may even have contributed to the static build-up on the rod. Personnel must be warned against these materials in chemical operations. 2. Vessel manholes should not be permitted to be opened indiscriminately, especially when there are flammable or toxic solvents in the vessel. 3. Where flammable vapors in the vapor space arc in the explosive range we should not introduce objects into the vessel which can be a source of ignition -- especially non-conductive rods or scoops. 4. Nitrogen was piped into the drop line to be used for facilitating the flow of slurry to the centrifuge. This was not used. In addition nitrogen was piped CMA 048817 to the bottom valve through a 3 cfm capacity rotameter to avoid absorption of air and control product color. Investigation showed that there was a slight flow through the plugged nitrogen rotameter. This flow was not sufficient to inert the vessel It is important to reaffirm periodically with each supervisor that he has instructed his workers about the differences between nitrogen for inerting and for other purposes. CASE HISTORY NO. 1934 Operators Exposed to Toxic Gases Description Four men became ill while working in the Liquids Department with one man requiring hospital treat ment. At the time, the men were handling a number of chemicals including amines, hydrochloric acid, and formaldehyde when one or more of them, or even a com bination, created sufficient vapors or gases which resulted in these illnesses. Preventive Measures: Both immediate and long range steps have been taken to prevent a recurrence including rearrange ment of production schedules, better housekeeping and major equipment changes on pumping, piping and vent sys tems. The man treated at the hospital lost 1 day of work. READER'S COMMENTS (a) -- The description of the incident referred to in Case History No. 1934 indicates that the operators were handling a number of chemicals, including hydrochloric acid and formaldehyde. Whenever formaldehyde and hydrochloric acid come together in ordinary humid air. bis-chloromethyl ether (BisCME) can form spontaneously. BisCME is one of the 14 carcinogens listed in the OSH A standards. The reaction of formaldehyde and hy drochloric acid in air occurs rapidly at ordinary room temperature of approximately 70F and 409!- RH, and a steady state level of BisCME is reached in less than one minute. Consequently, the possibility exists that these operators may have been exposed to an environ ment containing a carcinogen. If it has not been done already, this possibility should be investigated. (b) -- In contradiction of the reader's comment in the September issue that hydrochloric acid and formaldehyde in ordinary humid air can spontaneously form bisehloromethvi ether, we are asked to quote correspondence received from Dr, Marcus M. Key, Director of the National Institute of Occupational Safety and Health. He states in part that, based on continuing laboratory studies, it would appear that the spontaneous combination of HC! and formaldehyde does not result in production of detectable amounts of bis-CME (0.5 ppb) with reactant concentrations at below their respective Threshold Limit Values. However, measurable amounts of bis-CME are detectable at much higher concentrations of reactants. Dur ing these tests the reactants are equilibrated for as long as 48 hours under conditions approximating ambient room air temperature and humidity. CASE HISTORY NO. 1935 Valve Opened Unintentionally Description: A contractor welder received a fire permit t0 burn a hole in the toeboard of a process structure. As he was burning, his elbow came into contact with the handle of a one-half inch ball valve. The ball valve opened and spilled flammable liquid into the work area. The liquid ignited and the welder received first and second degree burns to his legs. Cause. 1. Easily opened ball valves with long handles. 2. Open ended valves containing flammable liquids which were not plugged when the fire permit was issued. Preventive Measures: 1. Replace all long handles on ball valves in drain service with "T" shaped handles. 2. Plug all open ended valves in flammable service when fire permit is issued. CASE HISTORY NO. 1936 Drumming Description: Employee drummed hot residue (375F) from a reactor into a used 55 gallon tighthead steel drum. He placed a screwed plastic bung cap in the opening and pro ceeded to wheel the drum away with a hand truck. Suddenly the hot residue erupted from the bung opening and splashed the employee with hot residue. He suffered second and third degree bums to his upper right arm. shoulder and chest. Cause: 1. The drum contained a residual amount of volatile chemical and was capped soon after filling, causing a build-up of pressure. 2. The hot residue softened or melted the plastic bung cap and the internal pressure forced the hot residue to erupt. Preventive Measures: 1. Instructed employees to use only completely empty used drums. 2. Provided a supply of steel bung caps and instructed employees to replace any plastic caps with steel ones. CMA 048818 CASE HISTORY NO. 1937 Tank Car Maintenance Description: Maintenance employee was removing bolts on the inlet valve on the dome of a tank car. He was using -104- ^crows foot tool, specifically designed for the job, and Bo using a 48" pry bar as a turn handle. When pressure applied, the wrench slipped and caught the employee's hand between the pr> bar and the tank car dome handrail. Cause: Special tool did not fit properly and the 48" pry bar was not a suitable turning handle. went into the exposed nip causing amputation of two joints of the middle finger and the end joint of the index finger. Preventive Measure: Grease fitting will be extended outside of guard and the plant will be thoroughly survey ed to correct any similar hazards that may exist. Preventive Measures. A proper turning handle will be designed and kept with the crows toot wrench A second man will be used to help keep stability on the wrench to prevent slipping. CASE HISTORY NO. 1941 The Pigeon Case CASE HISTORY NO. 1938 Transfer Line Description: Operator was removing a stainless steel dust cap from a transfer line. As he loosened the dogs, pressure trapped behind the cap forced it off suddenly. It swung upward, striking the employee in the nose. Cause' Employee failed to depressurize line correctly, and safety chain holding cap was anchored improperly. Preventive Measures' Safe operating procedure has been prepared. Safety chains on caps will be relocated. CASE HISTORY NO. 1939 Tank Maintenance Description: Employee was adjusting a grating on the top of a tank used to transport acid. The tank was being pressure tested prior to shipment, when the rupture disc suddenly blew and acid struck employee in the eye. resulting in the burn. Cause Rupture disc was weakened from corrosion, and test procedure required operator to be on the tank. Description A workman in a packing plant went, during working hours, to the dust extracting plant -- which he had no authority to do -- to catch a pigeon flying around in the roof. He climbed a vertical steel ladder to a platform where he apparently leant over some machinery and caught his clothing on an unfenced horizontal revolving shaft, as a result of which he lost his arm. The trial judge found that the workman's action was the height of folly, but that the employer had failed to fence the machinery . The judge apportioned 20 per cent of the blame to the employer. In upholding the award, Lord Pearce, in his judgment in the Court of Appeal, spelt out the social justification for saddling an employer with liability whenever he fails to carry out his statutory obligations. The Factories Act, he said, would be quite unneces sary if all factory owners were to employ only those persons who were never stupid, careless, unreasonable or disobedient or never had moments of clumsiness, forgetfulness or aberration. Humanity was not made up of sweetly reasonable men; hence the necessity for legislation with the benevolent aim of enforcing precautions to prevent avoidable dangers in the inter ests of those subjected to risk (including those who do not help themselves by taking care not to be injured). The accident in the pigeon case, it is true, would never have happened but for the unauthorized and stupid act of the employee. But then the accident would equally not have happened if the machinery had been properly fenced. --From the "Financial Times", June 1965-- Preventive Measures: Testing mechanism is being altered so that the test can be performed without an operator on the tank. The Job Safety Analysis has been rewritten. CASE HISTORY NO. 1942 CASE HISTORY NO. 1940 Mechanic Loses Fingers Description: An experienced maintenance man was attempt ing to lubricate the outboard bearing of a pinion gear that drove the ring gear of a steam tube dryer. To obtain access ^^khe lubricating fitting, the employee had to raise a spring Eroded guard access panel and, thereby, exposed an inrunmng nip between the gears. As he positioned himself to attach the grease gun fitting, a portion of the dryer struck his safety helmet causing him to lose balance. His hand Reaction of Bromine with Methanol Description: A young chemist was following a process, published in a highly esteemed book on biochemical prepa rations, which required the use of a solution of bromine in methanol. The manner of preparing this solution was not defined and no indication of potential hazards was pro vided in the text. The operator chose to use a measuring cylinder and a short time after making the solution a strongly exothermic reaction took place, ejecting the contents ot the cylinder. The operator sustained bromine bums to his face around the safety spectacles he was wearing; these for tunately protected his eyes from all but a small amount of bromine vapor. 10* CMA 048819 Subsequent investigation showed that mixing 9 ml, bromine with 15 ml. methanol, initially at room temperature, leads to rapid evolution of heat, the mixture reaching the boiling point in about two minutes. It appears that it was this ebullition, rather than an explosion reaction, that caused the mixture to be ejected from the relatively narrow measur ing cylinder Prcventiu' Measures. This incident underlines the necessity tor extra caution when preparing a mixture of reactants for the first time. It also shows how vital it is for workers in chemical laboratories to adopt adequate eye protection, and that descriptions of preparations in practical textbooks should incorporate more information about potential hazards. CASE HISTORY NO. 1943 Lock-out Failure Description: An operator suffered multiple lacerations to his left arm and bruised both shoulders as a result of an incident involving a blender, which turns 9Vi R.P.M. when operating. The operator has been employed for 14 months, holding his present position for approximately 12 months. Prior to holding this job. his industrial experience was limited to work in a laundry and some seasonal cotton gin w-ork. He is considered to be a good employee and has shown himself to be dependable and regular. The operator along with his crew foreman was scheduled to change a spray nozzle in the blender while a batch was being prepared for the first blending operation of the day. Nozzle changing and adjusting had been a very repetitive job because of an experimental program to establish optimum operating conditions that was instituted in early 1973. The plant has a formal written lock-out policy and a review' of past practices reveals that it is generally adhered to The operator went to the main disconnect switch for the No. 1 blender to lock it out, but found the cabinet containing that particular switch locked. The plant uses a night shift for a short seasonal period of each year and short term temporary employees are used to man these shifts. A problem developed because the night employees would improvise and otherwise tamper with elec trical gear and fuses. Because of this the switches were enclosed in wooden cabinets that are kept locked, as a means of forcing them to call for help. The keys for the cabinets are carried by the plant maintenance men. When the operator discovered that the cabinets were locked and he did not see the maintenance man in the immediate vicinity, he decided to go ahead wuth the job anyway. The blender had been rotated into a position that put the manhole adjacent to and just slightly above the on-off control switch. A fifty-five gallon drum was used to stand on to gain entry to the blender to work on the nozzles which are located inside near the top of the blender drum. In a standing position on the fifty-five gallon drum, the calf of the operator's leg was adjacent to the on-off switch. A second lock-out device on the on-off switch was over looked, since it w'as customary to lock-out at the main dis connect . No special instructions were given by the foreman since the job was repetitive and he had observed the operator when he went into the room where the switch gear is located and therefore assumed that the lock-out procedure had been followed. The operator entered the blender drum and changed the nozzle. As he was emerging his leg brushed against the on-off switch energizing it. The upper half of his body was still inside the blender at the time. The foreman who was standing by while the work was in progress immediately pushed the off switch, but the mixer had already moved far enough to squeeze the operator's shoulders and arm between the blender shell and the hinged door that he was working through. This accident would have been a fatality if the foreman had not been close enough to reach the switch in time. Causes: 1. Failure to adhere to established lock-out procedure. 2. Entering the mixer from the least desirable position. Preventive Measures: 1. Re-instruct all personnel on lock-out procedures. 2. Develop and implement an additional policy to control position of blender manhole for entry purposes. 3. Purchase and install "LOCK-OUT" reminder signs at critical locations in the plant, 4. Electrical switch gear cabinets will not be locked dur ing normal work hours. CASE HISTORY NO. 1944 Tank Filling Description: Operator was filling a propane tank and turned the vent plug counter-clockwise. In attempting to replace the plug with his bare hand, his hand was exposed to the escaping gases for a prolonged period of time resulting in a cold burn. Cause: Turning vent plug in wrong direction. Preventive Measures: Operators have been instructed to wear gloves when performing this operation, and the propane supplier will be contacted to see if a valve can be substituted for the present vent plug. CASE HISTORY NO. 1945 Acid Line Maintenance Description: Two mechanics were installing a new- acid line. They were bending over a sulfuric acid line in order to tighten bolts on the flange on the new acid line, when one of the mechanics bumped a 1/2" fitting on the sulfuric acid line which broke off, spraying both employees with sulfuric acid. -106- - CMA 04S820 Cause Corroded carbon steel fitting that had not been found ^vhen these fittings were changed to Alloy-20 a few years Ago. Preventive Measure: Thoroughly check all acid lines to be sure that there are no steel fittings in service. CASE HISTORY NO. 1946 Electrical Burns -- Lock-out Failure Description. Electrician was helping to repair a burned feeder to a furnace. He climbed up on a ladder to get into working position and took hold of A & B phase feeders. A phase-to-phase current passed through both arms and chest causing him to tall from the ladder and resulting in burns to both hands. Cause. Failure to completely lock-out switches. The current was produced by back feeding the auxiliary generator through a transformer bank at the substation. Preventive Measures: The work procedure has been changed as follows: 1. Safe Job Procedure checklist will be completed prior to the start of work. 2. Electricians will lock-out all power house breakers. 3. Physical disconnects will all be pulled to isolate the repair area. 4 The lock-out procedure will be reviewed with all plant personnel. CASE HISTORY NO. 1947 Pump Installation De.sa iptinn: A supers isor was splashed with a hazardous chemical when operator opened a valve. The material splashed out through a flange which had been left open after installation of a pump. The supervisor received first degree chemical bums to the left forearm, hip, thigh, and toot. Preventive Measures: 1. The need for more thorough job planning was reviewed and stressed. 2. Particular emphasis was put on completion of pump installation job CASE HISTORY NO. 1948 Potassium t-Butoxide ascription' Following a fire incident in which contact beccn acetone and potassium tertiary-butoxide was the prob able source of ignition, potential hazards of this alkoxide in the presence of their solvents have been evaluated. Two procedures were employed: a. Potassium t-butoxide (1.5 g) was placed on a gauze which covered a crystallizing dish (7 cm diameter) containing the solvent (15 cm3), the latter being pre warmed in some cases. b Solvent (0.5 cm') was dripped on to a small heap of potassium t-butoxide (1.5 g). The following solvents caused ignition, the induction period (minutes) and procedure used being indicated in parentheses: Acetone (4a, 2b), ethyl methyl ketone (la, 0.5b). methyl isobutyl ketone (3a), methanol (2b), ethanol (7a), n-propanol (lb), isopropanol (lb), ethyl acetate (2a). n-butyl acetate (2a), n-propyl formate (4a), acetic acid (3b), sulphuric acid (0.5b), methylene chloride (2b), chloroform (2a. Ob), carbon tetrachloride (lb), epichlorohydrin (lb), dimethyl carbonate (lb), diethyl sulphate (lb). Although we were already aware of the potential danger with water, acid and chlorinated solvents, the acute nature of the hazards associated with ketones, alcohols and esters, for example, was unexpected. It should be emphasiz.ed that little significant danger exists under normal reaction condi tions where excess of solvent dissipates the heat evolved. More particularly, we wish to highlight here the possible danger arising from accidental spillage of butoxide. --Chemistry in Britain, 17 Feb. 1973-- CASE HISTORY NO. 1949 What would you do if the Fire Bell rang? Description: A factory inspector rang the fire bell in an office block. Nothing happened until 2Vi minutes later when a secretary appeared and asked what the noise was. The firm was fined S250 for failing to take effective steps to see that employees knew their fire drill, --Evening Gazette, England -- 13 June 1973-- NOTE: In some office blocks the correct drill is to stay in your office until told to leave. CASE HISTORY NO. 1950 Skin Burns From Hot Plastic Resin Description: Thermo plastic resin product is processed by extruding hot molten resin from a header onto the surface of a chilled water bath in the form of small diameter strings or larger flat slats of resin. The material is chilled to the point of brittleness on the surface of the water and then chopped to form either pellets or slat-like chunks of product. As a result of excessively high flow rates, the chilled water temperature rose to the point that the resin w as insuf ficiently chilled and the strands began to break on the water surface. The operator slowed the resin pumps to drop the temperatures, donned gloves and cleared the surface of the water bath of the chunks of resin which had formed. He -107- CMA. 048821 then removed his gloves in order to feed the strands of resin across the water bath. At this time he put his hands into what he thought was cold water and was burned by a nearly invisible layer of hot resin floating on the water surface. The resin stuck to the fingers of one bare hand causing a bum. When the operator removed this resin from the fingers using his other hand, some burned tissue w'as removed from the back of the fingers. The work area was quite hot and there may have been some perspiration in the man's eyes. Lighting was of such a level that the operator could not dearly determine the presence of the resin layer on the water. Cause: The cause of the accident was the placing of hands in the relatively invisible layer of hot resin floating on the surface of the water. Poor lighting and a warm work area which may have allowed some perspiration to accumulate in the man's eyes making it difficult for him to see the surface layer of resin. Preventive Measures: 1. Lower the molten resin temperature in the feed header as much as possible consistent with maintaining acceptable flow characteristics. This will reduce the cooling load on the water bath. 2. Decrease the maximum possible flow rate so that the cooling capacity of the water bath will not be exceeded. 3. Install cooling fans to reduce the work area tempera ture to a more acceptable level, thereby reducing the likelihood of perspiration and attendant vision prob lems. 4. Improve the general lighting in the area. 5. Investigate alternative light sources which might increase the contrast between the resin and water layers permitting a better visual indication of the presence of a molten resin layer. 6. Alter the procedures for handling molten resin to per mit safe stranding without gloves or to permit con venient stranding using adequate gloves. 7. Investigate alternative methods of pelletizing and pro ducing slat-like chunks and thereby eliminate the necessity for manual handling of hot resin and permit high production rates. CASE HISTORY NO. 1951 Agitation of Superheated Liquid Description: A mechanical stirrer in a laboratory esterifica tion flask stopped due to some form of jamming. While the stirrer was stopped, the contents of the flask superheated to some extent. The stirrer was restarted by the chemist by hand twisting the shaft and the superheated material boiled excessively and ejected the stopper from the flask. Hot liquid sprayed on the arm and forehead of the chemist. |His safety glasses undoubtedly prevented injury to the eyes. We immediately washed himself in a sink and reported to the medical department where he was treated for first-degree burns. Cause: The accident resulted when the agitation of a superheated liquid produced excessive boiling which caused ejection of the flask stopper. Preventive Measure The investigating committee has agreed that in the future when a stirrer on a laboratory vessel stops for any reason, the contents arc to be cooled below the boiling point of the lowest boiling component before agitation is restarted. CASE HISTORY NO. 1952 Hydrofluoric Acid Burns Description: At 8 PM a chemical plant operator, while filling five gallon drums with 35% hydrofluoric acid, became aware of a burning sensation on his finger inside his glove. He sought first aid soon afterwards and emergency treatment continued until 10 PM when he went home. Subsequently when the severity of the bum was known his private doctor judged him unfit for work because of hydrofluoric acid burns on the left index finger. The operator was working overtime to fill the drums and had commenced this task at 5 PM. He was wearing the protective clothing required in the latest written operating procedures which included long (18 inch) PVC gloves. Older written procedures required lightweight inner gloves to be worn on acid service and the more experienced operators still observe this precaution. The drums were placed under twin filling hoses and filled visually. Some drums were overfilled due to inability to see the rising level in the drums. This overfilling caused the acid to form a pool in the recessed tops of the drums and this wet the operator's gloves as he screwed the caps on the drums before hosing off the excess. He had filled 100 drums before feeling the bum. Investigation showed a l/8" long crack in the PVC coat ing of the left glove at the base of the left index finger. This crack allowed water to pass through on test. These gloves had been used by other operators and had been casu ally picked up and used by the injured man. The operator had been employed about 13 weeks and had had verbal and written information on the hazards of hydrofluoric acid. He had not received follow-up training and demonstrations. This was the first time he had filled drums with acid. Cause: Defective PVC glove being worn in acid service. There is no convenient available means for testing PVC gloves for leaks before use with acid. The technique of filling the glove with water and squeezing leaves the glove wet inside and is not acceptable during cold weather. Preventive Measures: 1. Provide a convenient facility for testing PVC gloves for leaks. 2. Revise training methods to ensure all new workers in hydrofluoric acid service have complete informa tion on the hazards of this acid with emphasis on its different characteristics with different acid strengths. -108- CMA 048822 3. Revise written plant instructions covering the require ments for personal protective equipment and clothing for all personnel when exposed to corrosive chemicals. READER S COMMFXT A simple test rig can be made for gloves used in HF service Low pressure air (2-3 psig 1 can he connected through flexible hose to an appropriate!) sized, slightly tapered, wooden plug which has a hole drilled through it. A small bucket filled with water can be mounted near the plug arrangement The plug should not be painted. To test a glove, the wood plug is inserted into the glove opening so that a tight fit is obtained. The low pressure air is turned on and the glove held on the wood plug. The glove is then inserted into the water and any hole is readily seen since air bubbles will escape into the water. This proce dure leaves the glove dry inside. An extra precaution when handling HF is the use of an inner, light-weight glove. This type glove can be tested by the above method also. If a clean light-weight inner glove is used, it can also be tested by blowing it up like a balloon, holding shut, and seeing if it holds air. CASE HISTORY NO. 1953 Unbolted Cover Plate Leads to Hand Injury description: An operator inadvertently placed his left hand n a rotary valve while cleaning the area. W The injured reported for work at 23:45 hours. He went to the second floor of the flake building in the vicinity of the west (operating) dicer and observed that the area needed a routine cleanup, that is, collection and removal of loose flake, ordinarily from around the dicer blades. He further observed that the compressed air line used for this purpose was taped down, blowing air into the dicing machine. He therefore used an alternative means, a vacuum cleaner supplied tor this purpose. While vacuuming up the loose flake he noted that the Plexiglass cover plate on top of the dicer rotary valve was no! straight over the opening in the valve housing. He reached with his left hand to straighten it. but accidentally bumped it toward the opening in the valve housing. Instinctively he reached to seize it to prevent it from falling into the valve. In doing so, he placed his left hand in the opening in the valve housing and a rotating partition in the valve caught his left hand against the edge of the opening. He managed to free his hand but suffered amputation of the distal phalange of the thumb, distal and middle phalange of the index, middle and ring fingers of the left hand. The injured then w'ent to the local control station on the second floor and called up to the fourth floor control room. An ambulance w'as immediately called and several employees in the control room rushed to his aid. He was taken to the hospital for medical attention. evident Investigation' 1. There were no witnesses to this accident. 2. Pluggage, disassembly, and cleanup of the flake trans fer system are frequently experienced. Unplugging operations are carried out in part by manufacturing operators using light tools provided for disassembly of the flake line. 3. Although there were some minor operating problems immediately prior to the accident, area records show no downtime on the shift preceding the accident. The rotary valve was not jammed or stalled as a result of the accident. 4. The rotary valve is a constant-speed Sprout-Waldron model w'lth 3/4 HP drive. The housing opening is approximately .3" by 8". The rotary assembly has eight blades rotating at 10.5 RPM. Clearance between the rotary assembly and the housing is approximately 0.006 inches, 5. The original cover plate was metal, bolted to the housing. It was modified to allow venting of trapped air by installing a gooseneck vent. This modified plate was frequently removed so that the valve contents could be inspected. The metal plate was finally replaced by a 3" x 8" x 5/8" thick Plexiglass plate (w'lth 1/8" vent holes drilled through) so that the valve contents could be observed without removing the plate. 6. The Plexiglass plate had not been bolted down for at least two days prior to the accident. 7. The injured did not have a ring on at the time of the accident. 8. The injured stated that he climbed on equipment and piping during his clean-up operation and speculated that he may have dislodged the cover plate during this operation. 9. The injured was assigned to this area and was familiar with the equipment and its operation. Cause: Unsecure guard. The cover plate was not bolted down and allowed the injured to inadvertently place his left hand in an operating rotary valve. Contributing Factors: 1. The pellet transfer system has been a trouble spot since startup and the cover plate was frequently removed during troubleshooting operations. 2. No one who saw the unbolted cover plate prior to the accident recognized it as a serious enough safety hazard to require immediate attention. Preventive Measures: 1. Review area cleanup procedures and standardize via w'ritten procedures. 2. Analyze operating problems leading to pluggage. Recommend flake transfer system modifications to eliminate frequent pluggage. 3. Review this report with all employees, emphasizing the importance of following tag and lockout pro cedures when removing and replacing guards. 4. All rotary valve installations throughout the plant should be reviewed to assure that they are adequately guarded and that safe procedures for cleanout have been established. -109- CMA 048823 CASE HISTORY NO. 1954 Acid Burns on Legs Description Employee was helping replace a section of an acid line. The line was to have been cleared by blowing with air pressure. To accomplish this the operator would open a remote control valve so that air could be blown through An air hose was to be hooked up to the line and then blow clear. For some reason the remote control valve did not open, although the instrument indicated that it had. The valve was not visually checked by the mechanics, and they failed to put on full protective clothing. The line was pressured with air, and when they felt that it was clear they attempted to uncouple the air line, and the built up pressure blew acid out on the employee. Cause: Failure to follow instructions and check work as a sequence of jobs progress. Preventive Measures: Employees have been cautioned to follow all safety rules and regulations, and the procedure has been reviewed with all mechanics. CASE HISTORY NO. 1955 Back Injury Description: Operator stepped on drum lid. The lid slid on the floor, causing him to fall, striking his back against some drum rollers. Cause: Poor housekeeping, leaving lid on flooi and failure to recognize hazard. Preventive Measures Stack drum lids in proper place and maintain good housekeeping. CASE HISTORY NO. 1956 Puncture Wound -- Right Forearm Description: Two mechanics were removing a bearing assembly in order to clean out sulfur. Cap screws were removed from the cover plate, but the cover was stuck. In order to remove the cover, one mechanic inserted a screw' driver upside dowm through the sleeve bearing and gently tapped on the blade end with a hammer. A small piece of steel broke off the screw driver and struck the employee's forearm. Cause: Wrong tool for the job. ^Vereur/Ve Measures: Informed all maintenance employees of the accident, and instructed them to use the right tools for the job at hand. CASE HISTORY NO. 1957 Disposal of Sodium Azide A violent explosion occurred recently in the laboratory drainage system in a hospital in western Canada. The explo sion was caused by deposits of metal azides which had accumulated over a period of about three years during the continuous disposal of dilute solutions of sodium azide used in an automatic blood cell counter. It is estimated that about forty-eight pounds of sodium azide had been disposed of in a drainage system that was fabricated of copper and lead pipings. A number of similar explosions have been reported in other hospitals since the beginning of 1973. This information was provided by the Regional Safety Office of Labour, Canada. The following preventive measures were provided by the Explosive Research Labora tory of a major chemical company. Copper, for some reason or other, seems to be most often implicated in azide explosions. A solution of sodium azide, even with sodium hydroxide present, has an appreci able vapour pressure of hydrazoic acid over its surface. Such solutions must not, therefore, be stored in refrigerators or cabinets with exposed copper parts. In the presence of azide, moisture, and CCh, copper is capable of forming a series of complex or basic azides, all of which are sensitive explosives. In our operations we avoid the use of copper in rooms where azide is used. Where copper must be used, as in electrical equipment, we take care to avoid exposure to the air by using totally-enclosed fan-cooled motors, vapourtight conduits and fittings, and so on. In our laboratories no one is allowed to discharge azide wastes to sewer, regardless of the materials of construction If azide becomes mixed with acid in a sewer, hydrazoic acid is generated. This substance is a powerful and sensitive explosive. It will detonate spontaneously, without any exter nal ignitor or detonator. It is also highly toxic, rather like hydrogen cyanide. Before we dispose of azide wastes, wc destroy the azide by the following procedure: 1. If the waste is solid, it is dissolved in enough water to ensure an azide concentration of less than 59c. 2. To this solution a 20% solution of sodium nitrite (NaNCE) is added, until the quantity of sodium nitrite added is 1.5 pounds per pound of sodium azide (or equivalent) present. Mix well. 3. Very slowly and with continuous stirring (Caution! Good ventilation is required) a 20% solution of sul phuric acid is added until the waste solution is just acid to litmus. Toxic oxides of nitrogen (NOn) are given off. 4. When the acidified solution turns starch-iodide paper blue, there is excess nitrite present, and the decompo sition is complete. This method can of course be modified to suit special circumstances. Editor's note: The above, received from a reader of the MCA Laboratory Waste Disposal Manual, is copied from an article in The Fire Marshal's (Ontario) News. The recom mendations will be included as an alternative disposal proce dure in the Laboratory Waste Disposal Manual. -110- CMA. 048824 1 CASE HISTORY NO. 1958 i\ Tank Explosion Desc riprion: An explosion occurred in an accumulator tank. The manhole of the tank was open at the time of the explosion, and the blast was directed over the tank where a huge \cntilution duct was compressed. The sprinkler line was badly bent, and the two temperature control instruments on the wall close by were pulled loose and left hanging by the piping. A water line was also damaged and developed a rather severe leak An employee was filling molds about 15 feet away. The shock wave knocked him off a two-step ladder. He was not seriously hurt although he complained of a slight ringing in his ear. He reported seeing a blue flash at the time of the explosion A mix man had checked the temperature of the mix on the recorder just a few seconds before the explosion. He stated at that time that the manhole was open and the drop light was laying across it, but he thought nothing of the matter, as it has been the practice to leave the tank in this condition so the contents could be observed. He had left the catwalk and started toward the door when the explosion occurred. He also was uninjured. The tank contained about 650 pounds of mix, not enough to cover the agitator blades. The tank has a capacity of 800 gallons, and in effect was practically full of vapor. Following the explosion it was found that the inside of the tank was coated with soot and the drop light had parted from the electrical cord and was laying in the bottom of tank. The tank will withstand about 15psi pressure. ^rThe agitator motor was checked and found to be in normal working condition. Nothing was being run into the tank at the time of the explosion. The only possible source was the drop light. Apparently when the light parted from the cord and fell into the tank, the arc ignited the vapors causing the explosion. It was found that one ot the terminals on the light was quite loose: another one was tight but the wires had been sheared off. The light was a Crpuse-Hinds Model M-67 with UL approval for Class 1 Group D areas. A close examination of the extension light and the cord revealed that the rubber sleeve which fits into the handle of the light w'ax very large requiring a #14 cord. The cord actually installed on the light was a #18 which means that it was much too small for the rubber sleeve. Thus, when the flange on the end of the handle was screwed down to take the tension off the terminals, it failed to do so because the cord was undersize. It is approved practice in the department to keep the lids closed on all tanks unless it is necessary for them to be open for additions, cleaning, etc. Cause- Undersized cord on drop light allowed tension of the light to be carried on the terminals instead of the cord itself allowing the cord to pull away from the light. Also tank was not kept closed per approved procedure. mice Measures: The mix man was reprimanded for failure to close the manhole Drop lights will no longer be used in any flammable atmosphere in the plant. We will reserve the use of these lights for such things as tank cleaning, mainte nance inside tanks, etc. where there are normally no flammable vapors present in concentrated quantities. 3. Explosion-proof battery-operated lanterns will be purchased for mold filling which can be much more safely used in a flammable atmosphere. 4. The hazards of improper wiring of drop lights have been explained to the electricians. The drop light in question had not received any mechanical servicing for some time, so it is practically impossible to deter mine who hooked it up with the undersized cord, 5. All drop lights in the plant are being surveyed to determine if other cords are undersize so that they can be replaced. READER'S comment I wonder why the company which had the incident couldn't provide a sight glass opening on the top of the reaction vessel and then set a reflectorized light on the sight glass as a semi permanent installation. Light bulbs on chasers are too common a source of ignition to continue using them. When using an extension light in a vessel which is grounded we use a 12-volt lamp whose source of electricity is from an isolation transformer to avoid shock hazard from the live parts or from livening the vessel itself, w'here an unsuspecting person outside could lean against the vessel and be shocked. In addition we use an "SO" type cord which is a real heavy duty cord for the service. CASE HISTORY NO. 1959 Chlorine Exposure Description: An operator was subjected to a disabling exposure to chlorine while attempting to unplug a blocked line. After the last photochlorinator batch was made, the re maining chlorine in the lines was vented off to the scrubber. At 11:00 a.m. the pressure after the vaporiser was noted to show 0 kg/cm2 whereas the pressure reading before the vaporizer was 5 kg/cm2. It was then decided that there was a pluggage and that the chlorine would be vented through a temporary line connected to the pressure gauge connection. This did not work as the connection was also plugged. The temporary line was then removed to the transmitter connection. After opening the valve, the connection froze immediately, indicating that chlorine was indeed flowing through the line. When the ice disappeared, the chief decided to purge the line with nitrogen to remove all chlorine. At this time there was no pressure available on the chlorine line, the PG connection being plugged and the PT discon nected to allow connection of the temporary line. As soon as the nitrogen valve was opened, chlorine escaped in the granulation building from a nitrogen purged electrical panel, This indicated that the chlorine pressure was higher than the nitrogen pressure (5 kg/cm2) and chlorine had filled the nitrogen lines. Time was now 1:00 p.m. The nitrogen valve was closed, personnel evacuated from the building and all nitrogen purges opened to let the chlorine escape. CMA 048825 1 At 4:00 p.m. work was resumed in the granulation area. Around 6:00 p.m. chlorine vapors again escaped from the electrical panel. Work was stopped for IV2 hours. At around 10:30 p.m. with the night shift on duty, chlorine vapors again escaped from the panel. At around 12:00 p.m. three operators felt di7.7> and went to the first aid where oxygen was administered Feeling better, they resumed their w'ork around 2:00 a.m Monday morning. They did not work in the building anymore, but did a blending job outside. While two reported for work Monday night, one still felt ill and stayed home on his doctor's advice. (He went to the panel to sniff at the vapor at 10:30 p.m. Sunday, which probably explains why he suffered more severe symp toms than the other men.) Each ot you who is responsible tor the safety and health of at least one subordinate should remember this incident when you are too busy to instruct or train properly anj thoroughly. Consider those situations which, though remote could result in serious consequences and make the nme to warn against them. When you see an unsafe act \0u have a golden opportunity to find out w'hy it is being done this way. and then to correct it. Preventing a fatalitv is worth all the effort it takes even though you seldom can tell when you succeed. --From a Corporate Safety Bulletin-- I Cause: Improper procedure. 1. The primary cause was the purging with nitrogen when chlorine pressure was still high. 2. After chlorine got into the nitrogen line, this line w'as apparently not vented well enough. 3. No measurements were taken. The chief operator judged on the smell to decide that all danger was over. 4. The no-retum valve in the nitrogen line did not hold the chlorine. Preventive Measures: 1. Make 7 kg/cm2 nitrogen available for purging, so that chlorine pressure will never be higher than nitro gen pressure. 2. All production units to check if similar situation could develop in their department and make modification if necessary. 3. When purging a system, check pressure in line before opening purge valve. 4. Avoid using nose as a detection system when a poten tially toxic gas escapes. 5. Ecological group to set rules on how to meet in case of toxic escapes. 6. \To-rcturn valves -- critical service to be checked on a regular basis. CASE HISTORY NO. 1960 About a Fatality This month a terrible and puzzling injury occurred which resulted in the death of a worker. Although he was a truck driver, his daily tours inside the plant never subjected him to a fraction of the risk he encountered each day that he drove to and from work. We can only speculate on the exact series of events, but our investigators believe that he wanted to move another company truck which was blocking his way. The motor w'as running in this other truck and he put the transmission into drive and steered the truck w'hile walking along side of it. The truck passed too close to a metal pole and he Mas crushed between the truck's door and the truck's body. Pi is death resulted from multiple internal injuries and shock. It is very easy to shake our heads over his poor judgement but let's not dismiss this case at this point. CASE HISTORY NO. 1961 Furnace Explosion Description: An explosion occurred in a small dehydrator furnace during light-off. The light-off sequence was inter rupted and a full gas valve was partially open. The resulting explosion blew off a pressure relief door which landed some 50 feet away. The light-off control system was not installed yet and the light-off procedure had not been written. Cause: 1. Operator visibly checked (not manually) fuel gas valve. 2. The light-off control system was not working. 3. There was no light-off procedure written. Preventive Measures: 1. Two operators and a shift foreman must be present at the lighting of furnace. 2. Expedite a new light-off control system. 3. Continue to train and discuss with the operators hazards of lighting heaters. CASE HISTORY NO. 1962 Valve Maintenance Description: A safe work permit had been issued to zone maintenance employees to remove safety valves from the hydrocarbon cross-exchanger. The three-way plugcock was positioned so one valve could be safely removed, since there was a leak and pressure had bled off. When the other tube side safety valve was removed, it was still under pres sure and liquid hydrocarbon escaped Fortunately, the hydrocarbon did not ignite. The plugcock was frozen and could not be operated. Cause: Improper job line-up. A safe work permit was issued to remove relief valves so bleeder valves could be installed without seeing that pressure had been bled off the system. Preventive Measures: In the future, the entire system will be shut dowm if there is no reliable means of bleeding the system down. -- 112 -- CMA 048826 f CASE HISTORY NO. 1963 iler Loading Description: A hopper trailer had returned from the vendor and was spotted to be loaded again. The trailer had a nitrogen pad put on it before it left the vendor. The operator pulled a six-inch camlock cap off the trailer. Nitrogen pressure in the trailer blew the cap into his face. He sustained a broken nose and small laceration on upper lip. Cause. 1. Did not vent the trailer. 2. Lack of an adequate job procedure. 3. No loading checklist. Preventive Measures: 1. Use of crystaline natural soda ash should be reviewed in non-aqueous reactions for possible reduced activity compared to synthetic grades of soda ash. 2. More hazard evaluation on potentially hazardous pro cesses with emphasis on possible side reactions induced by probable contaminants. 3. Check for weakness in reactor system when hazard evaluation tests show that potential pressure may exceed design pressure of reactor components. 4. Fire and explosion resistant wall to separate hazardous process area from non-production facilities. Preventive Measures. 1. A job procedure will be written covering this loading situation. 2. A loading checklist will be put into use. 3. Disciplinary action will be taken. 4. Investigate DOT regulations. CASE HISTORY NO. 1964 Reaction Explosion CASE HISTORY NO. 1965 Drum Handling Description: A chemical operator suffered chemical bums of his mouth, chest and shoulders and minor eye irritation when he was splashed by liquid ammonia from a drum he was opening. Fortunately the man was wearing goggles and gloves and his quick use of the nearby safety shower prevented a more serious injury from occurring. The reporter claims that he cooled the drum using running water and released pressure in the drum by cracking the bung (both standard operating procedures) before removing it but enough pressure remained to cause the splash. ription: A chemical reaction of an aromatic amine with oro nitro compound went out of control due to ferric Preventive Measures: The responsible departments have side chloride catalyzed side reactions when the reaction mass became acidic. Natural soda ash used as an acid acceptor in the non-aqueous system was ineffective. The exothermic reactions developed pressures above those normally requested that additional protective clothing be worn during this operation in the future and a new transfer system is also under consideration. Lost time has been estimated at 40 days. encountered in the process. A weakness in the manhole closure caused the cover to blow off despite operation of a 60 lb. relief valve on the 100 psi designed reactor. Thrust of gases from the open manhole propelled the vessel down ward, releasing gases to the building where a combustion CASE HISTORY NO. 1966 explosion took place. Six employees were burned in varying degree, one later "Static" Ignition of Flammable Solvent died. Venting through large window areas of the building limited the amount of structural damage. Damage included Description: Static ignition of a flammable solvent being non-production areas separated from the process section by transferred by gravity to a 55-gallon drum resulted in a a wall not sufficiently strong to withstand explosion forces. flash fire and rather severe bums to an operator. Many sprinklers operated and fires were quickly brought A relatively viscous suspension of polymer particles in under control. p-xylene (approximately 27C flash point) was being trans ferred by gravity from a second floor crystallizer to a drum Cause: Natural soda ash was used in this batch as an acid ming operation on the first floor. The mixture at an esti acceptor instead of synthetic material which had been sued mated 40C was quite viscous and a 2-inch non-conductive successfully for over 20 years. In the non-aqueous medium polyethylene hose was being used for the transfer. A I Vi- the difference in crystalinity made the natural soda ash less inch stainless steel nipple was secured in the outlet of the effective than the synthetic type normally used; hence it hose with a metal clamp. acted like an undercharge of soda ash. This permitted an The receiving drum was purged with nitrogen prior to acid build-up which formed ferric chloride as the reactor filling; however, the purge was not maintained throughout was steel. Iron oxides were also present. the actual transfer operation. ^^boratory work verified the plant experience. However, The operation had been performed previously without t^^Uess of soda ash type no significant side reactions c^M be demonstrated if iron was absent. incident. One 55-gallon drum had been filled from the 340gallon capacity crystallizer without incident, and about 20 Confinement tests indicate the side reactions could develop pressure of 400 to 600 psi. gallons of material had been transferred into the second drum when the flash fire occurred. -- 113- CM& 048827 The fire continued, burning the drain hose, permitting the contents of the crystallizer to fuel the fire. Eleven sprinkler heads in the area of the fire fused, greatly facilitat ing fire control efforts by the fire crew which had been summoned. An auxiliary spray system was also activated. Eye witnesses indicate that the ignition occurred at the drum bung or just inside the drum. There appeared to be a puff and a ball of flame above the drum. The operator had just attempted to look into the small bung and was standing at the drum when the ignition occurred. Flaming liquid apparently spilled from the filling hose over the side of the drum and around the operator after the initial puff. The previously filled drum directly adjacent was not involved in the fire. The operator proceeded immediately to a safety shower about 40 feet away from the fire scene and extinguished the fire on his person. His safety glasses prevented eye injury. Cau.se: The most probable source of ignition was a static spark from the hose clamp or stainless steel nipple to the drum. The drum was grounded. However, the metal items at the end of the hose were not bonded to the drum or system. The low electrical conductivity of the p-xylene could have been a contributing factor in static generation even at the low unit flow rates associated with this viscous material. Air may have been introduced into the drum during filling; there had been no additional nitrogen purge during the estimated 30 minutes that filling had been underway. The flash point and solution temperature relationships were such that the vapor space would have been in the optimum flammable condition if nitrogen purge were insufficient to provide an inert atmosphere. Preventive Measures: 1. Insure that an inert atmosphere is provided in vessels when transferring flammable liquids. This becomes most important when materials are of high resistivity and therefore of high static generating potential. 2. Minimize the use of plastic pipe in the handling of flammable liquids. 3. Install dead-man automatic shut-off valves in system where continued gravity flow could create a hazard in the event of operator inability or inattention. 4. Use proper dip pipes, adequately grounded and bonded when filling drums or, if dip pipes cannot be used, items such as pipe nipples and hose clamps which might be used as substitutes should be properly bonded and grounded. All insolated metal objects should be properly grounded and bonded. CASE HISTORY NO. 1967 Hydraulic Jack Description: Two employees were repairing a leak at a flange of an 18-inch 90-pound steam line located near the ceiling in a basement area. A hydraulic jack was employed to spread the flange faces permitting removal of the old gasket and repair and cleaning of the flange faces. While the faces of the flange were being cleaned, the hydraulic jack failed or malfunctioned and an employee's fingers were caught between the faces of the flange. It was necessary for the second employee to reposition the h\. draulic jack and mechanically respread the flanges in order to release the injured employee. The flange was located in an awkward position above other pipelines being about 12 feet from the floor and some difficulty was experienced in getting the injured employee to floor level. The employee suffered contusions and abrasions of the left middle, index and ring fingers with fracture of the first digits. Cause: Direct cause of the accident was failure of the hy draulic jack coupled with failure to use a positive mechani cal stop between the flange faces. Preventive Measures: Use positive mechanical stops to pre vent closing when it is necessary for an employee to place fingers in a potential pinchpoint. These stops must be equip ped with a positive means of preventing inadvertent removal from the flange area. Establish regular inspection and testing schedules for hydraulic jacks used in this type of an application. CASE HISTORY NO. 1968 Agitator Not Turned On Description: Operator was pumping liquid material into a charge tank, but did not have agitator turned on. He turned on the agitator just as a second operator walked past the charge tank and material was splashed out on the second operator causing the bums. Cause: Pumping liquid material into the charge tank without having the agitator turned on to insure proper mixing. Preventive Measures: Operators have again been instructed never to pump into tanks unless the agitator is turned on and signs have been posted for this purpose. CASE HISTORY NO. 1969 Use of Hose Description: Technician was pouring nitric acid through a section of stainless steel hose, when it suddenly exploded, resulting in acid bums and puncture wounds. The hose had been used to sample phosphorus vapors and washed out with water. Cause: Using a strong oxidizing agent for cleaning purposes where other chemicals might be present. Preventive Measures: Review the characteristics and hazards of oxidizing agents with all chemists and tech nicians. -114- CMA 048828 CASE HISTORY NO. 1970 Ivent-Vapor Flash Fire Description: When employee upended drum to get residue of material into kettle, the bonding wire slipped off. He then lost control, dropping the drum into the loading funnel. A solvent-vapor flash fire occurred, during which he sus tained second and third degree bums on chest, abdomen, face and arms. Cause: Lack of protective blanket of inert gas. Preventive Measures: Mixers will be blanketed with inert gas while materials such as aluminum pastes are being loaded. CASE HISTORY NO. 1971 Fork Lift Incident Description: A fork truck operator was splashed by some cresylic acid after the truck he was operating damaged a drum and he tried to place it on its side to reduce the spillage. The acid contact caused second degree chemical bums of the man's chest, leg. arm and face and the estimated lost time has been set at 16 days. This injury was the result a series of events that started by poor housekeeping, seems that earlier this man was hand moving some drums when he stepped in a slippery material that had been spilled in the area and not cleaned up. Later this material on his shoe caused his foot to slip off the fork truck's clutch which caused the vehicle to ram the acid drum, creating the problem that resulted in the injury. CASE HISTORY NO. 1973 Fork Lift Truck Description: While driving a fork lift truck, employee acci dentally speared two drums on floor. After successfully laying down the first drum with the hole up, he attempted to tip over the second drum and spin the drum at the same time when drum got out of control. Employee caught his finger between the top of the drum and the floor and as a result lost part of the bone and the tip of his right ring finger. Preventive Measures: 1. Employee drove the fork lift with the forks about 12" above the floor. Emphasis was given on impor tance of having the forks within 4-6" from the floor. 2. Injured used poor judgment in attempting to lay down the drum. Emphasis was placed on importance of getting help. CASE HISTORY NO. 1974 Eruption During Equipment Start-up Description: injured received first and second degree burns from polymer eruption while starting up process. Cause: Employee was in process of starting up equipment when polymer erupted from die and landed on face, neck and forearm. Preventive Measures: 1. Additional protective equipment will be required. 2. Start-up procedure modified to reduce exposure to polymer eruption. CASE HISTORY NO. 1972 Near Miss -- Unloading Hydrochloric Acid Description: Two pipefitters started to repair a leaking hy drochloric acid transfer line and in preparation closed a valve to isolate the flange to be worked on. However, that valve was located downstream from the flange and nothing was done to close off the feed side of the line. Fortunately the line was not pressurized and they were able to break the flange without mishap but at this point they were not able to complete the job so they left the end of the pipe open and moved onto other work. Meanwhile, at about the same time this work was being done, a shipment of fresh acid was due but fortunately it was delivered late and when the line from the tankwagon to the storage tank was being blown, acid sprayed out the open end of the ^^e into the road. It should be noted that neither personnel ^Aponsible for the acid tank nor the materials management ^Tea were aware of the repair work being done and it was only a matter of luck the pipefitters were not at the open dange when the acid was delivered. CASE HISTORY NO. 1975 Acid Pump Rotation Reversed Description. Two chemical operators were splashed with 114.63% sulfuric acid when they attempted to pump acid from a drum, through a gear pump, into a vessel. Investiga tion revealed the splash occurred out of the drum when they first started the pump and further checking found the pump motor had recently been rewired, resulting in a reverse of motor rotation and material flow. It is normal practice to check the rotation of a pump after such work but since acid was already in the line this was not easily done and therefore was not. Fortunately the men splashed were not seriously injured. CASE HISTORY NO. 1976 Lack of Eye Protection Description: There were three preventable eye injuries as follows: Hot phosphoric acid solution splashed in eye from overfilled tank -- face shield mandatory but not worn. -- 115 -- CMA 048829  Metal chip struck eye while drilling hole -- no eye protection worn. Molten wax splashed in eye of lab technician -- no eye protection worn. CASE HISTORY NO. 1977 Exposure to Toxic Materials Description: Five incidents involved contact with toxic materials, as follows: Three workers had four cases (one repeat) of finger tip skin peeling caused by contact with acrylamide. A worker developed contact dermatitis on both hands when trichloroethylene entered gloves. CASE HISTORY NO. 1978 Man Burned While Demolishing Old Pipelines Description: Some old pipelines were being demolished. They were cleaned as far as possible and then tested with a combustible gas detector. No flammable gas or vapor was detected and so a burner was given permission to cut them up. While he was doing so. sitting on the pipes 12 ft. above the ground, a tarry substance seeped from one of the pipes and caught fire. The fire spread to the burner's clothing and he ended up in a hospital with bums to his legs and face. The tarry deposit in the pipe caught fire when it was heated by the burner's torch. The deposit was not flammable when it was cold so it could not be detected by the combusti ble gas detector. Preventive Measures: Everyone who has to bum or weld, or give permission to bum or weld, on pipelines or other equipment which may contain heavy oils or deposits should be aware that oils which are safe when cold will bum or explode when hot. It is almost impossible to make pipes which have contained heavy oils or polymers perfectly dean and therefore fires may occur when the pipes are heated. When demolishing pipelines there should be as many open ends as possible so that pressure cannot build up. Good access must be provided so that the burner or welder can withdraw from the burning point without difficulty if a fire occurs. CASE HISTORY NO. 1979 Unusual Accident Description: A platelayer at a steel works was using sodium chlorate solution to kill weeds. Some entered his shoes and dried inside. A few days later he was repairing a railway wagon. A spark fell into his shoe. The sodium chlorate exploded and blew away the front of his shoe. His foot was burned, but fortunately, not seriously. --From "Safety'', the accident prevention magazine of the British Steel Corporation, February 1973- CASE HISTORY NO. 1980 Chlorine Release Description: A pipefitter inhaled some chlorine gas when an airline union to a chlorine tank car was broken and some gas was released. In preparation for this job he had been told that section of the line had been isolated with closed valves on both ends and the contents bled off. He wa^ not wearing any personal protective equipment as he broke the union. The amount of inhalation was considered minor but this was complicated by the fact the man has a pre-existing respiratory problem. Lost time amounted to 4 davs CASE HISTORY NO. 1981 Exposure in Walk-In Type Hood Description: An engineering assistant developed an imita tion of his eyes as a result of chemical exposure while working at a walk-in type hood preparing a solution of ethyl acetate and hydrogen chloride. The exposure must have been slight during most of his work day spent at this job and it was not until the following day that his irritation made him visit Plant Health. Lost time due to immobiliza tion of the eye resulted in 6 days lost time. Since this incident an evaluation of the hood's efficiency has been requested, CASE HISTORY NO. 1982 Nitrostyrene Description: Three mechanics, all working together trying to unplug a nitrostyrene process line, were splashed with nitrostyrene causing injuries to their eyes, face, chest, arms and hands when a flange was broken on the pressurized line. As a result of these injuries, two men lost 2 days and the third 1 day lost time. Investigation revealed the men were not wearing any protective equipment when they began work on the flange nor had they checked on the status of the line being pressurized. Preventive Measures: Both lapses are considered violations of established safety practices and disciplinary action has been instituted as a result of this incident. CASE HISTORY NO. 1983 Acid Splash from Pipe Description: A supervisor suffered second degree chemical burns of the face, neck, eyes, hands and feet when he was sprayed by a 93$ sulfuric acid solution after a section of pipe he was working on failed. At the time the supervisor was attempting to replace a newly installed and potentially unsafe sample fitting with a smaller one when the "Chem Tite" pipe at the sample valve broke under the strain of the pipe wrench he was using. At the time the line was under the normal operating pressure of 35 pounds. After being splashed, he ran immediately to a safety shower where his fellow workers found him. He could not remember it -116- CHk 048830 he had put on his goggles before he started this work. Lost ^me has been estimated at 42 days. CASE HISTORY NO. 1984 Acid Plus Water Description: A chemist suffered chemical bums of the face, eves and hands when a sulfuric acid solution he was pouring into a sink splashed when water from the spigot entered the beaker containing the acid. Fortunately, he was wearing safety glasses and the resultant eye burn, only being super ficial, could have been more serious had he not been wearing them. Lost time amounted to one day. CASE HISTORY NO. 1985 Acid In Eye Description: A lab technician suffered an eye injury when some acetic acid she was handling splashed in her eye. She was in the process of pouring the acid from a bottle when she slipped on the freshly waxed lab floor and splashed herself while trying to regain her balance. At the time she was noi wearing safety glasses and because of this incident a mandatory safety eyeglass program is now being consid ered. Lost time amounted to three days. CASE HISTORY NO. 1986 Flange Failure Description: Mechanic was removing line under a crude oxychloride tank, and as he attempted to remove the last bolt the slip flange gave way, causing the line to drop. In his hurry to escape from the fumes, he hit his head on a leg of the tank. CASE HISTORY NO. 1988 The Girl Who Fell Off Her Shoes Linda Omohundro is a victim of high fashion. She fell off her shoes. The Marshall University senior said she was breaking in a pair of stylish new platform shoes recently when she took a tumble and tore a ligament in her ankle. She's been hobbling about on crutches ever since. "I was on my way to class when it happened." said the 21 year old blonde. "1 was just walking along when suddenly my feet got crossed and my ankle turned. Some thing snapped when 1 went down." The shoes had four-inch soles and seven-inch heels, she said. "That's what my doctor wanted to know," she added "The first thing he asked me was: "What kind of shoes were you wearing, those elevators?" Linda said her doctor warned her against the platforms "Actually, he told me 1 was lucky 1 hadn't been hurt any worse than I was. He said he had treated a girl a few days earlier who had broken three bones in her foot." Although her doctor wasn't available for comment, Dr. H. Darrel Darby, a vice president of the American Podiatry Association, said: "We're getting reports from all over the nation of similar accidents. These things are dangerous in that they make it hard to walk and hard to judge distance ... People who wear them are coming up with a lot of ankle problems and foot strains." Darby, who also is a member of the West Virginia Legis lature, said he would like to see the thickness of soles and heels regulated. "Style can't be regulated though," he sighed. "1 only hope for the sake of the people who are wearing these things that it is a short-lived fad." Linda said she probably will wear platforms after she recuperates even though she thinks wearing them is "sort of like trying to walk with roller skates." "And besides, I paid S29 for them." Came: Wrong type of flange. --From an Associated Press Article-- Preventive Measures. Slip flange was replaced with a welded flange which will break loose from the time the first bolt is loosened. CASE HISTORY NO. 1987 CASE HISTORY NO. 1989 Laboratory Explosion Capstan Car Puller Description Employee was moving a hopper car using a capstan car puller The U/2" rope became tangled on the capstan, and w'hile he was attempting to untangle the rope the car rolled backwards, tightening the rope and catching his left hand between two strands. Cause: Employee had not been properly instructed in the hazards of using the car puller. ^k-TC/u/Ve Measures: Safety Job Procedures have been re viewed with all employees working in this area, and a better car wheel chock will be obtained. An improved method of moving cars will be investigated. Description: A chemist and her assistant were concluding a laboratory synthesis of dichloroacetylene in dilute solution. Although this material is explosive when concentrated, its safety with proper dilution has been demonstrated. The same team had performed the synthesis six times previously with out incident. This time, however, as the chemist attempted to sample material which had collected in a water trap, a violent explosion occurred. Flying glass inflicted multiple puncture wounds of upper chest, arm, hand, neck, and face of both herself and her assistant. After emergency treatment by a physician, both, fortunately, were able to spend the night at home and return to work the next day. Each received periodic treatment during the following months, however, as additional glass fragments worked their way toward the surface of the skin. -117-- CM*. 048831 1 Had not both the chemist and her assistant been dedicated to the principle of the "safe way", habitually wearing eye protection, using gloves when indicated, shielding apparatus, etc., injuries might have been much more severe. Cause: While this synthesis was outwardly similar to the previous syntheses, the apparatus had been modified to increase its efficiency. This resulted in a lower coolant tem perature. allowing explosive liquid to be partially condensed from its carrier gas stream in a condenser intended to remove water only. The unexpected appearance of this "unknown ' material in the trap prompted the attempted sampling. Since dichloroacetylene is reported to be shock sensitive, the turn ing or even touching of the sampling cock could have initiated the detonation. The apparatus was adequately shielded during the syn thesis. During the sampling, the apparatus was thought to be in a safe condition, since reaction was complete, product had been absorbed in dilute solution, lines had been swept with nitrogen for some time, and condensers had been allowed to warm to permit volatiles to be purged. Therefore, some shielding was removed to give access to the product solution and the water trap. Because of this partial removal of shielding, glass fragments escaped the enclosure into previously protected areas when the trap exploded. Preventive Measures: 1. In future syntheses of this material (or of other vaporphase materials which are explosive in the condensed phase), chemical absorption rather than thermal con densation should be considered for removing water from the product stream. Unwanted condensation of the explosive material will thus be rendered less likely. 2. Provision should be made for remote sampling and manipulation, where possible, of apparatus containing potentially explosive material. Explosions, like radiation, obey the inverse square law, and the dis tance provided even by simple laboratory tongs can mean the difference between lost fingers and super ficial lacerations, should the unexpected occur. Per sonal protective equipment should include ear plugs, since the detonation caused an unpleasant ringing in the ears which persisted for several hours. 3. Shielding should remain in place until positive measures have been taken to disarm the hazard. Arrangements for such measures should be made before the synthesis or experiment begins. 4. Where remote manipulation is not possible, or when the point is reached (during disassembly, for example) that direct access cannot be avoided, personal pro tective equipment commensurate with the potential hazard should be employed. 5. When apparatus is modified or "improved' ' for what ever reason, the effect of the modification on the performance of the apparatus should be carefully analyzed to determine whether additional, unantici pated hazards might have been introduced. CASE HISTORY NO. 1990 |>il Disposal in Furnace Description: A fireman in a steam power plant disposed of about two gallons of waste lubricating oil by throwing it into the-furnace through the ash inspection door. The oil vaporized and ignited when it contacted the hot ash and refractory and the resulting flash-back burned the em ployee. The employee was burned on the arms and face despite long sleeves which afforded some protection for his arms and safety glasses which prevented serious eye injury. Failure to wear his leather gloves resulted in severe burns to the hands. A metal drum for the disposal of waste oil was located on another floor of the building. Cause: The direct cause of the accident was the disposal of lubricating oil by throwing it into the furnace. Preventive Measures: 1. Complete training of employees concerning hazardous properties of the materials which they handle. 2. Provision of adequate and convenient facilities for the disposal of waste. Discussion: The incident illustrates the common misconcep tion that high flash point combustible liquids are of no hazard since they will not bum at room temperature. On heating above their flash point they become flammable. In this instance the introduction of a relatively non-hazardous com bustible liquid into a high temperature environment resulted in ignition of a highly flammable vapor cloud. Similar incidents have occurred as a result of welding on vessels used for storing high flash point combustible liquids. Training and retraining employees to insure a complete understanding of the properties of all materials w'hich are being handled is a vital element in preventing accidents of this type. CASE HISTORY NO. 1991 Machine Cleaning Description: A machine operator suffered the loss of the middle and distal phalanges of the index finger and the distal phalange of the middle finger of his right hand. He was in the process of cleaning the motor casing with a shop rag when the rag became entangled in the drive chain and sprocket, pulling the fingers into the sprocket, resulting in the amputations described above. He immediately notified his foreman who transported him to a local doctor's office and then to a hospital for further treatment. Causes: 1. Unsafe mechanical condition -- improperly guarded; no backguard. 2. Unsafe physical condition created by employee by partially wrapping rag around hand. Preventive Measures: 1. Survey all line guards to determine hazardous condi tions created by inadequate guarding. 2. Have foremen review accident with employees to emphasize caution when cleaning around moving equipment. -118- CMA. 048832 CASE HISTORY NO. 1992 etylene Cylinder Fire Description- At approximately 1:10 AM. an explosion was heard by the operators in the No. 2 Control Room Flames were observed approximately 10' to 15' abo\e the floor on the second lex el The operators attempted to call the Fire Department number but dialed 200 instead ot the Fire Department No. 2000. The shift electrician contacted the Night Superintendent, who sounded the Fire Call The Night Superintendent went to the scene of the fire. The wheels of the cart for a portable welding unit were on fire, a small fire was observed underneath the cart and the top of the acetylene cylinder was burning. Hand fire extinguishers were used to extinguish the fire. Cause: The cylinder was found to be defective and leaking where the top plug seals into the body of the cylinder. The unit had been used until 8:00 PM on the preceding day when the valves were shut and the unit was stored on the second level. This was confirmed by the Night Superintendent who said he attempted to close the valves on the cylinder and found them already dosed. The source of ignition could have been one of the following. 1. Acetylene decomposing on the hose of the welding rig2. The spontaneous reaction of chlorine and acetylene in the department. (Several heavy chlorine emissions occurred during the shift.) 3. A spark from an electrical conduit which was located ajvout 3' from the welding rig. The fire at the base of the portable welding unit was probably caused from the welding hose which had wrapped around the top of the rig. Apparently it had burned, weakened, and fell to the base of the unit while still burning. The fire around the cutting unit created a dangerous situation. Acetylene can detonate at elevated temperatures. Unignited acetylene vapors also create a hazard if ignition occurs after the vapors are mixed with air. Acetylene cylinders have three lead plugs in the bottom designed to melt and relieve pressure in a fire. The plugs have an opening of 1/4". The cylinder has two plugs in the top for pressure relief. Each one has a hole of approxi mately 1/8" in diameter. The holes are filled with a low melting compound, which is designed to relieve pressure in the cylinder when the temperature at the top of the cylinder reaches 215F. The plugs at the top of the cylinder had melted allowing most of the vapor to escape and bum. The most serious hazard involved in fighting a fire in the immediate area of an acetylene cylinder stems from the fact that acetylene is an unstable compound and will detonate. The detonation hazard is minimal at ambient temperature but the hazard increases with increasing tem perature. The type of fire where the acetylene cylinder is enveloped in flames from an external source should be distinguished from a fire which may involve only the plug or neck of ^e cylinder. Fires involving only the plug or neck of a P^linder are not nearly as dangerous as a fire surrounding the cylinder from an external source. Minimal hazard is involved in this type of incident as long as an excessive time delay is not involved from the start of the fire until attempts are made to extinguish the fire. Each supervisor should recognize that every cylinder in his area represents a potentially serious safety hazard. These cy linders should be removed from the departments and build ings as soon as possible after use. It is apparent that some confusion exists in the plant concerning the number to be used in calling in a fire. This obviously needs to be emphasized. Rapid reaction to plant fires is critical in limiting the extent ot the fire and the danger to personnel involved in fighting the fire Preventive Measures. 1. A fire permit should be required for any cutting rig which is used in a department or building. The permit should be made out for a specific period of time. After this time has expired, and provided a new permit has not been issued, the cutting rig should be removed from the department, 2. All plant telephones should be equipped with the Fire Department and Dispensary emergency numbers. 3. The defective acetylene cylinder should be tagged so it will not be refilled. CASE HISTORY NO. 1993 Canning Operation Description: Because of lack of time, the chief operator asked for help from two canning operators to clean the filter. When the door came open, fumes escaped. The injured lost consciousness and fell down from the one meter high platform. He recovered consciousness as soon as he was brought into fresh air. He was then brought to the first aid room and from there sent to the hospital, where he was under observation for two days. Investigation: 1. The canning operators are not familiar with this equip ment. 2. It was established that the filter is routinely cleaned in the following w<ay: a. After the filter operation, the vent valve is closed, and nitrogen pressure is used to push the product to the tank on the first floor. b. Vent valve is opened again, nitrogen valve is closed and nitrogen pressure vents off via scrubber. c. Operator pushes door ajar with face turned away while fumes come out. d. Operator immediately leaves platform and leaves door ajar for approximately 15 minutes. e. Finally door is completely opened. 3. In this case everything went faster than normal. So: -- residual nitrogen pressure can have been pres ent when door was opened. -- the unexperienced operators did not turn their face. The injured was caught before he could leave the platform. 119- CM& 048833 Causes' Inadequate training. The injured unfamiliar with the equipment and the hazards. He most probably lost con sciousness through inhalation of nitrogen. Preventive Measures. 1 Use only trained canning operators on production jobs. 2. Run a water line to the filter and make the following sequence mandatory: --- After venting off nitrogen, fill filter with water (while vent valve remains open). This will push Na out to the scrubber and coo! down filter. -- Drain off water. Air will then enter filter as it now does with door ajar. -- Only then open filter door. CASE HISTORY NO. 1994 Tank Car Loading Description: Loaderman was opening the fill hole closure cover on an acid tank car prior to loading. As he loosened the swing bolt which retains the cover, the bolt slipped off and the cover was forced open by internal gas pressure in the car. It blew off the employee's safety hat and safety glasses and iron rust struck the employee in the face and eyes. Cause: Unusually high internal pressure in the tank car, and wrong body position contrary to standard procedure. Preventive Measures: Written job procedures have been reviewed with all loadermen, and another method of venting cars will be explored. CASE HISTORY NO. 1995 Sulfur Unloading Description: Employee was attempting to unload a liquid sulfur car. The car had been heated, but sulfur was not melting properly around the unloading line. A steam lance was inserted into the unloading line to assist in melting the sulfur. As the employee turned off the steam and pulled the lance from the dipped tube, hot water erupted, splashing his face, forearms, and wrists resulting in the bums. Cause: Steam and hot water was trapped under the sulfur, and when the lance was removed pressure blew water out on employee. Prevemne Measures: This procedure will be avoided in the future. If there is no other way to melt the sulfur, a shield will be installed to protect against splashing. CASE HISTORY NO. 1996 Acrylonitrile Exposure ^Description: One of the duties of the operator is to carp out frequent equipment operating checks of the purificatioi area. On one of .these routine checks he noticed a leak 0n one of the seals on the pump. The leak was fairly heaw and crude acrylonitrile was spraying out around the area of the pump. After consultation with the shift supervisor, it was decided to change to another pump and to send the leaking pUrtlD over to maintenance to have the seal bellows and seating^ changed. While engaged in isolating and decontaminating the leak ing pump it is assumed the injured was contaminated by crude acrylonitrile, although he has no actual recollection of being splashed. He was wearing safety boots. The injured completed the shift with no indication of bums..Later in the evening, small blisters appeared on both feet. Blistering progressed during the night, the injured received medical attention the next morning and was hos pitalized for treatment. Cause. Failure to wear correct footwear. Preventive Measures: Personal protection must be worn when working in immediate vicinity of liquid leaks, spillages of acrylonitrile or flooded areas. CASE HISTORY NO. 1997 Corroded Valve Description: Operator was adjusting valve on an acid treat ing filter when a leak developed due to corrosion, resulting in phosphoric acid spraying onto the employee. He was wearing safety glasses with side shields, but this was not adequate protection. The accident was not reported until the following day. Cause: Corrosion caused leak in equipment. Preventive Measures: Procedure will be changed so that all acid plant treating operators will wear face shields, plus safety glasses. Closer checks will be made on equipment for corrosion damage. CASE HISTORY NO. 1998 Drum Handling Description: Employee had placed a drum on a scale using a fork lift and drum lifter. He noticed that the drum was not placed properly, and while attempting to move the drum manually the scale tilted, causing the drum to slip off and catch the employee's hand between the falling drum and a second drum nearby. Cause: Manual movement of the drum caused the scale to raise up on one side, allowing the drum to slip off. Preventive Measures: Employee has been reinstructed in the proper manner of handling drums, and the maintenance department has been requested to find means to prevent the scale from tipping. -- 120-- CMA. 048834 CASE HISTORY NO. 1999 halation of Bromochloromethane Description: Employee inhaled bromochloromethane gas when a pluggagc gave away in a steel clad rubber hose on a Fenwal pressure sensing device while the bomb was being replaced. It had been noted that the relieving device on a null in the building had ruptured requiring replacement. It was not known that the hose was plugged with product and that the pressure in the hose had not been relieved into the system. As employee started to loosen flange bolts preparatory to bomb replacement, pressure in the hose caused gas to be discharged into his face, making him ill. He was hospitalized for inhalation and lung congestion due to chemical gas exposure. Causes: 1. Upset condition. Plugged hose on pressure detection system. 2. Failure to take precautions prescribed by line breaking procedure. Preventive Measures: Deficiencies in the Fenwal system had been noted, and corrective action had been initiated prior to the accident. In approximately a year and a half operation of five Fenwal devices, no pluggage of the hose lines had been observed. Fenwal technical specialists are being asked to assist in correcting system problems. CASE HISTORY NO. 2000 Sprayed with Sulfurie Acid Description: Employee was switching to a clean, in-line filter on the 66 sulfuric acid product line to storage. When he opened the outlet valve on the clean filter he was sprayed on the right forearm, stomach and right thigh and suffered second and third degree burns. Causes 1 Misaligned filter cap which did not properly seat the gasket. 2. Failure to re-install the protective plastic cover over the filter when the filter cartridge was replaced some time earlier, Preventive Measures: 1. Concerned employees reinstructed on the proper method of installing filter cartridges. 2. The use of protective plastic covers over the filters was re-emphasized, 3. Job Safety Analysis written on filter change over. CASE HISTORY NO. 2001 Caustic Splash in Eye description: A plug cock valve below the foot valve on *e bottom outlet of a caustic car was leaking and had to be replaced. As injured removed the valve it dropped into the drain pan under the car causing some caustic to splash out. A droplet of caustic got behind the man's safety glasses and into his right eye. Causes: Failure to wear specified protective equipment -- splash goggles or face shield with safety glasses. Preventive Measures: 1. Enforce use of splash goggles. 2. Drain pans arc to be washed out before repair work under cars. 3. Eye wash fountain to be relocated. CASE HISTORY NO. 2002 Chlorine Cell Repairman Falls Description: Injured fell IVi feet onto concrete floor and fractured his left ankle, elbow and wrist. He was on top of a diaphragm chlorine cell w ith another employee to remove a 5 inch plastic pipeline that connects the cell to the chlorine gas heater. It was part of a routine cell maintenance procedure. The connector pipe was dif ficult to pull loose so the repairman kicked the base of the pipe and pulled upward to release it from the cell cover. His hands slipped off the smooth plastic pipe and he fell backward off the top of the cell. Causes: 1. Poor design -- connector pipe was jammed at bottom; difficult to pull from top. 2. Failure on part of employee to maintain firm grip and stance. Preventive Measures: 1. Shorten connector pipes so they are easier to remove. 2. Use non-slip type gloves. 3. Job Safety Analysis to be written and employees further instructed on safe job procedure. CASE HISTORY NO. 2003 Adhesive Coating Machine Description: A structural products operator had the tips of his left ring and little finger crushed in the rolls of the Fome-Cor adhesive coater. Surgical amputation of the distal phalanx of both fingers was required. He was attempting to remove excess glue from the foam sheet as it entered the adhesive coater. Cause: Lack of a safe procedure for removal of excess glue from the adhesive coater was the primary cause of this accident. A contributing factor was inadequate design of the glue feed tray, allowing the glue overflow to drop on the foam. Preventive Measures: 1. A safe procedure has been developed for removing excess glue from the adhesive coater. 2. The glue feed tray has been modified to overflow at the end of the tray so that excess glue will be less likely to accumulate on the foam sheet. -- 121 -- CMA 048835 3. A highlighted safety cable has been installed above the level of the foam sheet. 4. Install a guard on the west side of the adhesive coater to prevent improper access to the adhesive coater. 5. All employees have been advised in department safety crew huddles of the sate procedure for removing excess glue. the delivery pipe when one of the metal hooks on the si(je of the spout caught on his jacket. He attempted to free it with his left hand while holding the full weight of the spout with this right hand. A gust of wind caught the spout swinging it outward and pulling the employee off the car > Cause: No adequate work platform or lifeline available CASE HISTORY NO. 2004 Preventive Measures: Permanent lifeline will be installed for all rail car bulk loading stations. Contusion, Right Shoulder Description Employee was blowing water out of an air hose, when a Chicago fitting came apart and the hose struck the employee on the right shoulder. Cause: Employee failed to fasten the Chicago fittings to gether with wire, in accordance with standard practice. Preventive Measures: Reinstruct all employees on the proper procedure for securing Chicago fittings. CASE HISTORY NO. 2005 Laceration of Right Thigh Description: Operator stepped down into a shallow pump pit in order to make an adjustment on a pump. As he stepped down into the pit he struck his right leg against a protruding valve stem, resulting in the injury. CASE HISTORY NO. 2008 Distillation Column Rupture Description: An acetone distillation column ruptured when the only vent on the system plugged. Full steam pressure caused the weakest of the seven sections to blow out. The solids causing the pluggage were identified as ammonium bicarbonate, ammonium carbonate, and ammonium carbamate. These solids either sublimed or de composed and recombined in the cooler sections of the sys tem and accumulated in the single pipe vent on the system. When this pipe plugged solid, full steam pressure caused the column to rupture. Preventive Measures: 1. Reduce steam pressure. 2. Provide overpressure protection on the column. 3. Periodically remove solids from the distillation system, vent line and storage facilities. Cause: Failure to remove unused defective valve. Preventive Measures: Valve has been removed, and operators have been instructed to watch carefully for all types of hazards. CASE HISTORY NO. 2006 Ink Splash in Eyes Description: Employee was assisting operator to position a can of printing ink under the ink supply tray at a coating machine. In doing this they were pushing against and bend ing the short rubber return line hose backward, however, because of the rigid construction of this hose, it whipped forward splashing ink on the two employees. Cause: Rigid return line hose. Preventive Measures Install a more flexible hose with suit able connectors for easy removal, and instruct all employees to keep their safety glasses in a good state of repair. CASE HISTORY NO. 2009 Chromic Acid Waste Description. A student was cleaning glassware related to his undergraduate research work. One vessel for cleaning was an unlabeled 250 ML Erlenmeyer flask containing about ML of green dark liquid, which was taken to be organic waste material. When added to the large collection bottle for organic wastes, however, this substance caused a violent reaction which ejected the waste contents out of the bottle, some landing on the student, mainly on the nose, neck and forehead, causing minor burns. Waste material was in all likelihood actually spent chromerge cleaning solution, i.e. chromic acid. All workers will be re-instructed on the necessity of properly labeling all filled vessels in the laboratory. CASE HISTORY NO. 2010 Line Rupture CASE HISTORY NO. 2007 Multiple Muscle Strains Description: Loaderman was working on top of a bulk car. He was attempting to attach a metal extension spout to Description: Three operators were taking a slurry gravity line out of service so that maintenance could change out an expansion joint. The line had been emptied as much as possible, block valves were closed and the line was being steamed out with one-half inch steam line. Steam was com ing out the bleed lines on both ends of the pipe, through the hole in the expansion joint and seeping out from under -- 122- CMA 048836 the insulation near the middle of the line. Injured employee ok a valve wrench and started knocking off the insulation locate the other leak. The line ruptured, blowing steam, hot water and slurry into his face. He was wearing a hard hat, face shield, and safety glasses. Cause 1. Striking insulation on pipe in an area of a suspected steam leak. 2. The pipe was dangerously thin and needed only a slight blow to cause the rupture. Preventive Measures: 1. Make thickness measurements every three months and replace pipe that is specified for 150 pound steam service. 2, Job procedures will be changed to require that all pressure be bled down before any work or checking is done. Cart did not have a side panel to prevent operator's foot from extending off the side of the cart and very little foot room inside. Preventive Measures: 1, Employees shall be given training on the proper opera tion of these vehicles, emphasizing the dangers of protruding feet and the driver's responsibility to be familiar with his equipment and to operate cautiously. 2. Ensure equipment contains controlled acceleration on all vehicles and side panel or other enclosure in the area where the operator's feet are rested. Future carts should have four wheels instead of three to make them more stable. CASE HISTORY NO. 2013 Defective Welding CASE HISTORY NO. 2011 Maintenance -- Machinery in Motion Description: Employee, after starting compression machine, decided the upper punches needed grease. With grease on the tip of his right forefinger, he applied to the punches' while machine was in motion. The rotating punch caught the tip of his forefinger and pulled it into the stationary xam (pinch point). Wause: Employee used finger to grease rotating punches (a small brush is provided for this purpose). The employee was shortcutting the procedure. Preventive Measures: 1. Stress in safety meetings awareness of the dangers of moving machinery and the importance of adherence to operating procedures (speed of short cut should never be placed before safety or quality). 2. Supervisors will make more observations for devia tions from operating procedures. CASE HISTORY NO. 2012 Operation of Electric Vehicle Description: Employee was approaching the control room in a three-wheel electric cart. As he moved to apply the brake, his foot hit the accelerator instead and the cart lurched forward. The left rear wheel of the cart hit a four-inch high step which tilted the cart, throwing the employee's left foot out of the cart. The cart continued forward and to the left, and the employee's foot was caught between the cart and the corner of the control room. He sustained four broken bones in his foot and one in his ankle. Description: Two operators were pushing a wheel-mounted belt conveyor (20 ft. long, 6 ft. high, 2 ft. wide). One wheel support failed along the welded joint. The belt con veyor rolled over, hitting one of the operators, who was caught with his leg between the conveyor and the ground. Cause: Defective welding. Preventive Measures: 1. All belt conveyors checked. 2. Contact manufacturer to get new conveyors modified. CASE HISTORY NO. 2014 Loading Sulfuric Acid Description: Loaderman had filled a sulfuric acid car with a dome vented atmosphere. As he attempted to tighten the deep line cap with a wrench, air pressure in the deep line forced the loosely connected cap off, and acid spurted out, splashing on the employee. Cause: Acid in the deep line caused compression of air during the loading process. Air pressure caused the cap to be forced off the line, and acid splashed out of the open line as the acid rapidly filled the deep line to the level of the loaded car. Preventive Measures: All deep line caps and safety vents will be removed from sulfuric acid tank cars before filling in the future. CASE HISTORY NO. 2015 Lift Truck Cause: Employee inadvertently stepped on the accelerator Jither than the brake (not the cart he normally used and e was not familiar with it). Cart did not have device for controlled acceleration as most carts have (it lurches when the accelerator is depressed rapidly). Description: Operator was preparing a tote bin for packaging by removing the top cover, which is 7 ft. above floor level. In order to reach this cover the employee stood on a cut-out hole on the Hyster frame used for a step. The bin u'as at ground level and the forks were positioned under the bin. While reaching for the cover with his left hand, he 123- CMA 048837 placed his right hand on the Hyster frame for support. Hy draulic system leaked off pressure, thereby lowering the hoist which pinched the finger of his right hand. Cause: Employee committed an unsafe act by failing to follow instructions which called for descending from the lift truck and using a ladder to reach the top of the tote bin. Pmennve Measures: Operators have been instructed to follow Safe Job Procedures and not use lift trucks as step ladders. CASE HISTORY NO. 2016 Pipe Fitting Description: Supervisor was observing a pipe fitter remove a section of pipe. As the pipe fitter struck the pipe flange with a hammer, ice from above the pipe rack was dislodged, fell, bounced off a piece of pipe and struck the supervisor on the front edge of the visor of his hard hat, resulting in a laceration over the eye. Cause: Ice formed because of a small condensate leak, and striking the pipe line caused vibrations which dislocated the ice above the pipe rack that had not been noticed Preventive Measures: Employees working on pipe lines during w'inter months have been instructed to clear all over head icc from the immediate work area. CASE HISTORY NO. 2017 Derma'titis from Nitro Compounds Description: Employee reported his dermatitis to hands, arms, neck and face to doctor. Cause: Possible contact or inhalation of dust or vapors of nitro compounds. Preventive Measures: 1. Allergy test on each employee. 2. Toxicological studies on several intermediates. 3. Improved operations and personal protective equip ment. CASE HISTORY NO. 2018 Chlorine Cell Description: Explosion occurred in low pressure chlorine header system, causing damage to header, coolers and drier. Damage to compressors from moisture. Cause was loss of brine level in one series of cells, result ing in boiling, rupture of diaphragm and passage of hydrogen into chlorine header. Explosion occurred after corrective action had commenced and power had been switched off. Cause: Level control was valved off without proper tagging or notations in the log book. Level was controlled manually. insLiuiiiciii wtis reiurneu u.) serviLe vvunout opening vaj when manual control was discontinued. Level was |0s,Ve ensuing 30 minutes. Level alarm operated from same le ^ sensing device. e Preventive Measures: Added second source to alarm |0 level. Re-emphasize need for written communications he tween operators and from shift to shift and from maintenance to operations. CASE HISTORY NO. 2019 Sodium Chlorate Shipping Incident Description: While enroute to his destination and about four hours after loading, the driver of a bulk cargo tank truck trailer of dry sodium chlorate noticed "smoke'' issuing from the trailer. He found the cargo tank to be hot. According to procedure, he immediately notified the nearest fire department and the shipper-producer. Both responded imme diately and monitored the situation until the trailer was returned to the producer's plant. The uninsulated parts of the unit became hot to the touch, and gases could be heard issuing from the vent. A cargo hatch was opened to provide additional venting. A chemical reaction continued in the tank for several hours. The decision was made not to apply water to the tank as a steam explosion was a possibility because of the high temperature. Upon subsidence of the reaction, the vehi cle was moved to the producer's plant, the contents washed out, and the tank was inspected and returned to service. The cargo tank had previously been in ammonium thiosul fate service, and prior to that had carried tallow, and had been washed and inspected by the driver before sodium chlorate loading. Cause. Subsequent investigation indicated that decomposi tion of the sodium chlorate had occurred, triggered by residues of ammonium thiosulfate. Two reaction mecha nisms were suggested. The first reaction between ammonium thiosulfate and sodium chlorate produced sulfur trioxide, water and nitrogen oxides which were responsible for the second decomposition reaction initiated by sulfuric and nitr ous or nitric acids. Under controlled laboratory conditions, a small quantity of ammonium thiosulfate in sodium chlorate could be made to decompose explosively. Preventive Measures: A thorough cargo tank inspection and cleaning procedure has been initiated which involves defining previous ladings, complete inspection of the interior tank top, hatch interior and underhang, fittings, and addi tional cleaning if required. CASE HISTORY NO. 2020 Contaminated Dichloromethane Description: During laboratory analyses, dichloromethane (CHs Ch) of pesticide quality was found contaminated with an unknown substance. Two incidents occurred. A 60 ml sample was evaporated to about 2 ml to concen trate impurities for testing by gas chromatograph. As evapo- -124-- CMA 048838 ration was nearing completion, the solution changed from to greenish color. Suddenly, an orange flash was ^Icserved just above the liquid. Several days later, when the laboratory attempted to deter mine the contaminant, a detonation occurred when a sample portion was being concentrated above a steam bath. CllUSe 1 Mixtures of water with the contaminated dichloromethane or concentrates of the dichloromethane oxi dized iodide to iodine. The reaction is rapid at room temperature. 2. The contaminant appears highly acidic when extracted into water from the dichloromethane or from concen trates. 3. The contaminated dichloromethane smells very slightly like bleach before evaporation and very strongly of bleach as concentration continues. 4. Adequate allowance had been made for the hazards of fire and toxicity of the concentrated contaminant. However, detonation was not considered and was unexpected. Preventive Mensures: 1. Utilize iodide determination for oxidants and pH of water extract as tests for contaminated dichloro methane until the contamination problem is com pletely resolved. 2. Continue to use water extraction to clean up any contaminated dichloromethane. Assure adequate clean up with the iodide and pH testing. . Remind all personnel that work with materials of uncertain hazard potential should be carried out in an isolated area with appropriate shielding or bar ricading. CASE HISTORY NO. 2021 Molten Metal Burn Description: Operator was skimming slag from the surface of a molten aluminum bath. As he lifted and tilted the shovel to drain the aluminum off, it popped backwards and a hot piece fell inside his boot, burning his foot. Cause: Shovel was cold on the back and as the hot aluminum hit the cold surface, it popped. Preventive Measures: Thoroughly preheat equipment used to clean reactors, and additional protective clothing will be provided. CASE HISTORY NO. 2022 Foot Caught in Screw Conveyor Description: According to the two more experienced ^fcerators. they had "lost their recycle" and were hurriedly Backing the unit to determine the problem. They decided to check one particular screw conveyor to see if a pin had sheared. However, they decided the problem was elsewhere and left the area of the screw' conveyor involved. The injured, who had very little experience on this job, but, who was anxious to be helpful, decided to check the screw conveyor himself. He removed a section of cover from the screw conveyor. When he did, one corner of the cover dropped down into the screw (which was turning) and pulled him off balance. In attempting to regain his balance, he stuck his left foot into the screw conveyor. This will result in the loss of the left foot above the ankle. Cause: 1. Removing section of cover while screw was running. 2. Injured had worked seven months as a utility man. Nine days before the accident, he successfully bid on an opening for a first-class operator's job. This opening was temporary and several more experienced men did not bid for the job because it was temporary . In jumping from utility man, directly to first-class operator, the injured by-passed several steps in the line of progression. This inexperience was certainly a factor. Preventive Measures: 1. Accident will be publicized and discussed at all safety meetings. 2. Have emphasized and will continue to re-emphasize equipment lock-out rules. 3. In the future, men who by-pass one or more steps in the line of progression will be given closer supervi sion and training than is normally given. CASE HISTORY NO. 2023 Automatic Valve Failure Description: A control valve was equipped with a carbon steel yoke suitable for the particular concentration and tem perature of sulfuric acid being handled. However, the temperature was increased and, at times, water was used on packing leaks. These resulted in corrosion of the retaining ring groove in the yoke which allowed the retaining ring to work loose and the yoke to come off when the pipeline was pressurized. Since the packing follower on this type of valve is a part of the yoke, the packing loosened and sulfuric acid sprayed from the packing gland onto an em ployee. He did not receive a more serious injury because he was wearing proper protective equipment, had positioned himself with his back to the malfunctioning valve, and promptly flushed the area of contact with water. Preventive Measures: 1. The half-round portion of the replacement retaining seat was machined to be square and the split stainless steel rings were changed from a round cross section to a square cross section. 2. The carbon steel yokes in valves handling the acid at the particular strength and temperature involved were replaced with 316 stainless steel. 3. Operators were instructed not to put water on any acid valve packing leak to avoid forming weak acid which would accelerate corrosion of the valve compo nents. -- 125 -- CMA. 048839 CASE HISTORY NO. 2024 Fork Lift Wheel Blows Apart Description: A maintenance man received a very serious injury to a finger when the wheel of a fork lift blew apart as he was removing the wheel from the fork lift. He was knocked backward from a squatting position and was lucky he did not receive even more serious injuries. Cause: The injured was removing the wheel to check the brakes. He had removed all but one of the 3/4" lug bolts that secure the wheel to the hub. w'hen the split-type wheel blew apart. An outside concern fixes all flats, changes tires, and replaces wheels. They had fixed a flat and replaced the wheel on the fork lift, with the two halves of the rim not secured together. Five 5/8" bolts are supposed to hold the two halves of the split-rim together. Two of the five bolts had been twisted off during some previous work. It was obvious no nuts had been on the other three bolts for some time. The lug bolts used to attach the wheel to the hub were all that were holding the rim halves together. When the injured removed four of these five lug bolts, the 70-80 lbs. of tire pressure blew' the two halves apart. There was no way the injured could be aware of the condition of the w'heel. Preventive Measures: I. Have installed solid (foam-filled) tires on this and similar equipment. Note: A message was stamped on the side of the rim, cau tioning to let air out of the tire before removing the wheel. After a day in our plant environment, it is doubtful this message could be read and most likely, no one had occasion to see the message w'hen the rims w'ere new. CASE HISTORY NO. 2025 Explosion in a Gas Fired Air Heater Description: An improper setting of a linkage controlling the gas-air mixture to the burner on a process air heater resulted in the flame being gas-rich for about an hour. After an adjustment w as made the additional air supplied permitted the formation of a combustible mixture with the unbumed gas that had accumulated in the air heater fire box and recycle loop An explosion occurred which damaged equip ment. The burner provided the source of ignition. Preventive Measures: 1. Provide instructions for adjusting the heater system safely. 2. Use an oxygen analyver to analyze recycle gas to permit safe adjustment of the air-gas ratio. 3. Pin or weld the existing control linkage so it cannot be changed once properly set. ^ CASE HISTORY NO. 2026 Sulfuric Acid Loading Description: Employee was loading a 65% oleum tank car T when the rupture disc blew. Employee was standing 0n the car platform when he was burned by SO.t that blew from the vent cap. Cause: Failure of rupture disc on tank car. Pressure buildup was caused by blockage in the vent line. The hose had crimped and material became frozen inside the hose. Preventive Measures: A pressure gauge has been installed on the vent system, and a new collecting system with blower and absorber has been installed on this loading rack. CASE HISTORY NO. 2027 Operation of Electric Vehicle Description: An employee was backing a 4-wheel Cushman electric vehicle in a congested aisleway in the warehouse. When he turned his head to the right to look backward, his left foot also turned to the right, and his heel was perpendicular to the vehicle -- protruding approximately five inches. The operator then backed into a parked fork lift, catching his heel, and broke both bones in the left leg three inches above the ankle. Cause: The operator created an unsafe act; however, inves tigation showed there is not enough room to place the driver's left foot comfortably if his shoe size is larger than size 7. Preventive Measures: We have four electric vehicles of this nature (one 4-wheeled and three tricycle-style). In our opinion, they are not designed safely enough to be used in industry, so we are fazing them out and replacing them with standard pick-up trucks until the electric-vehicle indus try engineers more safety into vehicle design. CASE HISTORY NO. 2028 Wrong Chemical Used Due to Inadequate Labeling Description: To obtain some de-ionized water to use in making a weak acetic acid solution, the employee went in the direction a fellow employee indicated and filled a beaker with what he thought was de-ionized water from an unlabeled plastic carboy, which actually contained so dium azide solution. After acetic acid was added he detected a strong odor and his eyes began to water. He promptly flushed the material down a sink. The hydrazoic acid evolved from the mixture of chemicals is highly toxic. Preventive Measures: 1. The laboratory was surveyed for unlabeled containers and they were discarded, 2. Personnel were reinstructed to properly label all stor age containers and not to use material from unlabeled containers. -- 126-- CMA 048840 "1 CASE HISTORY NO. 2029 Htic Anhydride Explosion and Fire Description: A large, horizontal, dished head, aluminum, outside storage tank containing crude acetic anhydride exploded after being ignited by sparks from a nearby cutting torch l! is beliesed that the sparks fell on the tank and limited sapors emitted Irom a small hole in an explosion venting panel or around a pressure relief cap. The resulting fire caused an 8-ineh sent cap on the tank to open but the internal pressure exceeded the sent cap's capacity and caused one of the 24-inch square explosion relief panels to be blossn off. The relief panel svas blossn approximately 40 feet onto a second floor open platform of an adjacent building. Fortunately no one svas injured and the fire burned out when the oxygen inside the tank was consumed. Cause: The accidental ignition of vented vapors from low boiling contaminants in the crude acetic anhydride within an improperly sealed storage tank. Preventive Measures, 1. Introduce an inert atmosphere in the vapor space of the tank. 2. Initiate a more rigid and thorough inspection of all tanks, 3. Do not allow any fire producing system in the area of the tank without proper shielding. CASE HISTORY NO. 2030 Tank Entry -- Fatality Description: A shift foreman suffered fatal injuries when he v iolated tank entry procedures and entered a reactor alone. The reactor is a glass-lined vessel, six and one-half feet in diameter and approximately nine and one-half feet deep, with an eighteen-inch oval manway on the top. The night shift had experienced problems with the reactor. The day shift emptied and water-washed the reactor. All the members of the work crew went on break except the foreman w ho wanted to make a final inspection of the reactor interior to decide if additional washing would be required prior to starting the next batch. The foreman apparently spotted an old Teflon manhole gasket lying in the bottom of the reactor. It is assumed that he decided to remove the gasket so the next batch could be started after the break. He obtained a rope ladder (the equipment that is normally used to enter the reactor). He apparently reasoned that he would only be in the reactor long enough to retrieve the gasket and therefore he could see no valid reason for having a second man present outside. He entered the reactor, picked up the gasket and tied it around his waist to allow his hands to be free to climb back to the ladder. He slipped and fell and was knocked unconscious. He was found fifteen nutes later on his back with his head tipped back. He s dead, having swallowed his tongue, suffocated. Cause: Failure to follow tank entry procedure requiring an observer outside the tank. Preventive Measures: 1. An evaluation is being made of the general attitude toward safety, particularly with respect to manage ment's role in the safety program. 2. Tank and vessel entry procedure is being revised and employees will be instructed on the new procedure which will be enforced. CASE HISTORY NO. 2031 Contact Lenses Description: Now that more people are wearing contact lenses, more hazards peculiar to their use are being discov ered. A shipyard worker was wearing safety glasses over his contact lenses when he opened a 440V box to connect a welding cable. When the circuit breaker was opened, the breaker arced and a flash occurred. When he later tried to take out his contact lenses, largeareas of dried cornea came off his eyes with them. Doctors were able to save his eyesight. They found that the contact lenses had served to concentrate the heat of the arc flash onto the cornea of the eye, which was consequently dam aged. Contact lenses should not be worn under safety specta cles, nor in any area where arc flash could occur. Comments: (a) Following the publication of the original article on the accident and injury, the treating doctor stated that on the basis of additional information provided by the injured, that the injury may have resulted from failure to carry' out even the simplest precautionary measures, by wearing the contact lenses for something like 17 or 18 hours without taking them out. This alone could account for the drying effect beneath the contact lens and the lifting off of the corneal epithelium when the contact lenses were removed from the eye. The doctor does, however, feel that intensity of heat from the flash bum could cause drying of the tears beneath the contact lens with a similar result. (b) The Consultant Ophthalmic Surgeon (Department of Employment) has given his view: --- "It is extremely likely that the contact lens, whether it may be made of glass, plastic or the soft lens, would reduce the penetration of ultra violet light if not eliminate it completely, so that a person wearing contact lenses might be regarded as more protected than one not doing so. If he was wearing micro lenses the sclera and conjunctiva would not be covered either, but even so protection would be given. On the other hand there is no doubt that if a micro contact lens wearer did sustain a flash bum he would have some degree of ultra violet kerato conjunctivitus, and this might be further irritated by the lens. 1 certainly do not regard this as a serious problem, and would not suggest that anyone should stop wearing his contact lenses if he was likely to have a welding flash. Indeed, on balance, I would be rather in favor of them." On this subject doctors in the Employment Medical Ad visory Service recommend: -- "Those who wear contact lenses and believe themselves to have been exposed to the risk of arc eyes should immediately remove the contact lenses before the resultant changes in the cornea have time to develop." --Chemical Industries Association-- -127 CMA 048841 CASE HISTORY NO. 2032 Unloading Error -- Explosion and Fatality Description: A tank truck of water solution of Sodium MBT (sodium mercaptobenzothiazole) was misdirected to an area where maleic acid anhydride was stored. The maleic anhy dride operator did not follow operating procedures, and with out checking the shipping papers of the truck hooked it to the MAA transfer line and started transfer operations. The mistake was discovered 20 minutes later, but by this time an exothermic reaction between the materials was uridvwjy, This resulted in an explosion which propelled the stor tge tank 75 feet to the entrance of two production areas. In the fire which followed the explosion, there was one lability and several minor injuries. Puveniive Measures: Steps taken to prevent a recurrence include labeling of tanks and filling connections, analysis of all incoming raw materials, positive routing of truck shipment within the plant, and checking of shipping papers and analysis. CASE HISTORY NO. 2033 Explosion -- Chemical Laboratory Description: Two 3 kg bottles each of styrene and methyl acrylate (vinyl monomers) were left on a lab bench for use the following morning. The bottles were sealed and contained an inhibitor. One bottle of methyl acrylate was old and partially polymerized although still sealed. During the night one or more of the bottles exploded. The others were broken by the explosion. The room was littered with pieces of polymer and broken glass. No one was present at the time of the explosion. The incident was discovered about 10 a.m. the following morning and reported to campus maintenance. Preventive Measures: 1. Vinyl monomers which are not used within eighteen months of purchase are disposed of. 2. Vinyl monomers which have been distilled to remove inhibitor are stored under refrigeration and disposed of within one week. 3. A yearly safety seminar is being instituted for the entire department. 4. More emphasis is being placed on the safety lecture given at the beginning of the polymer laboratory classes. he was wearing his monogoggles with the top edge aro the rim of his hard hat. With the aid of the helper immediately went to the shower/eye bath in the vici'njte and washed eyes and face. The ambulance was called a a washing continued 15 minutes until he was transported the hospital. 0 | i . Cause: Storing equipment not positively known to be ciean Proper wearing of monogoggles would have prevented eye injury, although it was not expected to find contaminated liquid in this store. ' Preventive Measures: 1. Only completely clean equipment should be stored in this area, which may mean dismantling, cleaning and reassembling prior to storing. 2. Store will remain monogoggles area. j 1 ! CASE HISTORY NO. 2035 Electrical Shock Description: Employee was operating a two-inch brine line valve while standing with one rubber boot on an electrically energized chlorine series and his other boot on an insulated platform. With one hand still on the valve, he reached across to a metal handrail support on the series to pull himself into a standing position, He received an electrical shock, was momentarily unconscious and fell to the floor level, approximately 8V4 feet below. He fractured his right arm at the elbow when he struck the concrete floor. i j 1 t Cause: 1. Inadequate handrails on the operating platform (it is seldom that any operator would be in a position to fall off the platform). 2. Reached across to operating series handrail with hand still on grounded brine line (the operator failed to pay attention to the job he was performing). 1 Preventive Measures: 1. Increase awareness and vigilance through an in-depth educational program about all building electrical hazards. 2. Install additional handrails on cold brine platforms. 3. Require rubber gloves for brine and acid valve operation. 4. Consider means of insulating the handrail support post. CASE HISTORY NO. 2034 Chemical Storage Description: As the shelves in the store were leaning forward a bit, it was decided to take off all the equipment and fasten the shelves to the wall. A helper on the top shelf handed over pieces of equipment to employee standing on the floor. While handing over a DP-cell, a corrosive liquid came out of the end of the flange and splashed employee's face and right eye. The liquid got into his eye because CASE HISTORY NO. 2036 Line Maintenance Description: Injured employee was attempting to unplug a line containing asbestos. Air had been valved into the line in an attempt to remove the plug, and cell effluent had inadvertently gotten into the line. The operator then attempted to rod the line out. The line unplugged suddenly and the air pressure forced the slurry' out of the line with enough force to dislodge his chemical goggles. Both eyes were exposed to the slurry. Even though he went to an -1 28- CMA. 048842 eve bath immediately, he suffered loss of sight in his right ^ye and minor chemical bums to the left eye. Cliu sc: 1 As a new employee, he failed to realize the danger of attempting to rod the plugged line out with air pressure in the line (there were no written procedures and this employee had not been adequately trained). 2. Piping was not properly designed and plugging problems were common. 3. Cell effluent was not supposed to have been in this line and plugging asbestos had not been considered dangerous. Preventive Measures: 1. Redesign asbestos system to eliminate plugging. 2 Forbid air use to unplug any lines -- must dismantle or mechanically dear. 3. Rewrite job procedures to include abnormal condi tions and reinforce job training of operators. CASE HISTORY NO. 2037 Ethyl Acetate -- Flash Fire -- Fatality Description: An operator was fatally burned in a flash fire in a chemical synthesis plant. An explosion and flash fire resulted from ignition |bf ethyl acetate vapors escaping from a 400-gallon Pfaudler jacketed reactor. A valve between the reactor condenser and adjacent receiver was closed while the valve on the steam inlet to the reactor jacket was left at least partially open The reactor cover was closed, but the two clamps in use were not tightened down. Preventive Measures: 1. Building has been partially opened to provide natural ventilation. 2. Equipment layout improved. 3. Operating instructions rewritten with emphasis on valving procedures. 4. Flammable gas detectors installed in area. 5 Electric installations reviewed throughout the plant. CASE HISTORY NO. 2038 Drain Eruption Description: Equipment was under nitrogen purge to remove remaining air and methanol (methanol had been used for testing purposes after repair). Some nitrogen was blowing out of drain valves at approximately 1.50 meters above ground level. Employee bent over to pick up a hose just as some liquid blew out of a drain, hitting him in the face. |His safety glasses were blown away and liquid (methanol, Contaminated with benzene, toluene and possibly traces of hydrogen sulfide) splashed his eyes. He was taken immediately to a nearby safety shower where his eyes were washed out thoroughly. Cause: Draining to atmosphere at unsafe location (all drains had been checked out prior to opening the valves and nitro gen was blowing out all valves so employee expected equip ment to be free of liquid). Preventive Measures: Standing order has been issued to use full face masks or chemical goggles at all work at or nearby open drains. CASE HISTORY NO. 2039 Hexane Vapor Cloud Ignited Description: A hexane spill resulted when a pump was disconnected that had not been adequately isolated. The resulting vapor cloud was ignited by a welding arc approxi mately 20 feet away from the spill. Cause: 1. Inadequate check on condition of pump. 2. Hot work permits approved in area too close to operat ing plant. Preventive Measures: 1. Additional tagging procedures implemented. 2. Plant shut down until all hot work completed. 3. New tagging procedure introduced. 4. Review of existing procedures and practices regarding permits and hot work areas. CASE HISTORY NO. 2040 Lock-Out Procedure Description: An operator was severely injured in an accident which resulted in the loss of his left foot above the ankle. The employee removed a cover from a screw conveyor to check to see if it was running. As the cover was lifted, the operator lost his balance and stuck his foot into the screw conveyor. The accident occurred near the end of the shift and it was assumed the operator and his co-workers were in a hurry to solve the apparent problems with the conveyor before the shift change. The injured employee is nineteen years old. He had been on this job approximately one week. He had been a utility man and was promoted through several steps of progression directly to a first-class operator. Cause: Failure to follow lockout procedures and lack of experience and training. Preventive Measures: 1. Lockout procedures are being re-emphasized 2. Orders have been issued that no one is to remove covers or open any inspection doors while equipment is in operation. Consideration is being given to in stalling inspection ports. -- 129-- CMA 048843 CASE HISTORY NO. 2041 Chlorine Description: Hydrochloric acid leaked at a flange and dripped onto a three-inch liquid chlorine line, resulting in a major gas release. The shift foreman took his men next door to the office so he could use the telephone and get the location of the leak. By this time the vapors were getting thick, so everyone used their respirators to reach a pickup and were driven out of the block. The chlorine was too strong for the respirators and everyone received some gas exposure. Four men were hospitalized as a result of this exposure. One of the rescue men on the ambulance that had been dispatched to pick up the men who had been exposed also was hospitalized because of chlorine inhalation. The leaking chlorine line was vented into an empty tank which is maintained empty for emergency pur poses . Cause: 1. A leaking liquid chlorine line (HC1 line located directly above the liquid chlorine line caused serious corrosion problems when the flange leaked). 2. There was a delay while the foreman attempted to locate the leak and the respirators were used up before the employees could escape in the truck. 3. There was a 4 MPH wind and the vapors did not dissipate with such light wind -- it was difficult to determine which direction to go to get out of the chlorine. hot naphthalene to surge from low points in the 1,700 foot long line. Preventive Measures: 1. The procedure "Breaking Into Pipelines" has been revised to emphasize the need for extended "Bleed-off" time to prevent "eductor effects." f0p lowup training on this revision is underway. CASE HISTORY NO. 2043 Measuring Tank Contents Description: While climbing down ladder of a 400-bbl. tank at customer's location, employee missed the hand rung and fell 20 feet to the ground. He sustained a fractured leg. Cause: 1. Working at unsafe speed and inattention. 2. Type rungs on this tank and oily condition of tank. Preventive Measures: 1, A method will be developed for determining the amount of fluid in a tank without climbing ladders and standing and walking on the tops of flush tanks. The use of hydrostatic sight gauges is being inves tigated. 2. Work with customers and tank suppliers to improve the condition of these tanks. Preventive Measures: 1. Acid lines have been relocated so leaks won't damage liquid chlorine lines. 2. All maintenance employees have been through a safety training program including the usage of respira tory equipment and the limitations of each piece of equipment. 3 All liquid chlorine lines, both inside and outside block limits, will be inspected regularly and inspection reports kept on file. CASE HISTORY NO. 2042 Pipeline Maintenance Description: A supervisor was testing the oxygen content of a naphthalene pipeline in preparation for cutting and welding. The pipeline is a 1,700 foot transfer line from the dock storage tank to a department tank. It had been pumped out and steamed out. The only valves in the line are located at the dock tank and were closed and tagged out. Steam tracers on the line in the department were dis connected. Nitrogen was fed into the line for inerting. Pipe line flanges were then unbolted at the top of the tank and the line was opened to the atmosphere. The supervisor tested the oxygen content at that point. When he made his second test, the naphthalene "burped" out on his ankles and feet. Cause: Unsafe method. Investigation revealed the cause to be a failure to recognize that the nitrogen purging of the naphthalene line created an "eductor effect" causing CASE HISTORY NO. 2044 Steam Purging Description: Operator was steam purging a line prior to welding. He neglected to close a steam valve in the line just prior to removing a sewer plug which had been installed to provide a nitrogen purge some time earlier. When the plug was removed, and as a result of the steam valve being left on, steam condensate discharged through the plug opening, striking the employee. He received second de gree bums to back and stomach. Cause: 1. Failure to relieve steam pressure prior to removing plug. 2. Assuming unsafe position, directly in front of plug, prior to removal. Preventive Measures: All operating personnel received additional instructions concerning proper steaming out and plug removal procedures. CASE HISTORY NO. 2045 Moving Equipment Description: Employee was attempting to remove a piece of unblown plastic from a molding machine with his hand. The mold hung partially open, and as the plastic was -130- CMA. 048844 jemoved, the mold snapped shut, mashing and amputating right index finger. Cause 1. Failure to shut the machine down to remove the plastic. 2, Used his hand instead of longs or a stick to remove the plastic. 3. Inadequate guarding. Preventive Measures: 1. Revised procedures, added more guards, announced serious disciplinary action (discharge) for violations. 2. Re-audited safety attitudes, practices and equipment. CASE HISTORY NO. 2046 Purge Valve Description: A separator (salt-caustic solution) had plugged. The operator shut off the inlet valve to the separator and tied in a condensate hose to a flush valve connection between the separator and the block valve. The flush connection was 4.5 feet above the floor and projected horizontally. After flushing, the operator opened the inlet valve to the separator, putting it back on line. He shut off the condensate and disconnected the quick coupling at the purge valve with out closing the valve. Operator was struck with 50% caustic at 130C, but his eyes were protected by monogoggles, fcmployee suffered third degree bums to face and parts of P-'dy Cause: 1. Purge valve pointed out at anyone in area. 2, Hose removed without closing purge valve. Preventive Measures: 1. All purge valves, sample valves reviewed as to loca tion and corrections made if required. 2. The unit will be shutdown for 24 hours for an intensive training period to update everyone's awareness. CASE HISTORY NO. 2047 Ethylene Description: A deep well pump was being replaced into the well suction barrel. Ethylene gas escaped from the barrel and was ignited by crane engine. Liquid ethylene in the barrel was vaporized rapidly following contact with warm pump. A maintenance foreman and a contractor crane operator received second and third degree bums on face and hands. Cause: 1. Equipment (suction barrel) was not purged gas free. 2. No written Job Safety Analysis. 3. Suction barrel not gas tested. Preventive Measures: 1. Nitrogen or steaming out to be used to gas free all equipment prior to release to maintenance. 2. Review of Job Safety Analyses -- Write new' ones as required. 3. Increase safety showers in tank farm area. 4. Use A-frame hoisting equipment in preference to motorized crane on jobs of this nature. CASE HISTORY NO. 2048 Screw Conveyor in Motion Description: The operator started screw conveyor in order to empty a cyclone hopper of urea. He checked operation of the screw conveyor by inserting his finger in a 1 Vi inch drain nipple located on the bottom of the conveyor. His finger was caught in this screw, resulting in amputation at the first joint. Cause' 1. Employee's failure to realize nipple opening led into body of conveyor. 2. The drain nipple was left open when it should have been plugged. Preventive Measures: 1. Provide longer nipple with valve to prevent fingers from reaching the screw, 2. Re-write job procedure to emphasize mechanical hazards. 3. Upgrade understanding of job procedures by operators. CASE HISTORY NO. 2049 Valve Maintenance Description: Employee had overhauled a valve actuator and had mounted it on a new six-inch Teflon-lined butterfly valve to test the unit. He unplugged the power cord and the valve began to close, since it is air-operated both ways and controlled by .i solenoid valve. The movement of the valve flapper caused the valve to move toward the edge of the workbench and start to fall off. He instinctively reached to catch the falling valve and his right ring finger was caught between the closing flapper and the body of the valve. The finger was damaged so badly that it was necessary to surgically amputate at the first joint. Cause: 1. Valve was not clamped in a vise. 2. Valve was too near the edge of the workbench when the test began. Employee did not realize that the flapper could cause the valve to fall. 3. Instinctively reaching for the falling valve (employee did not think about the danger of the closing flapper as he reached for the valve). Preventive Measures: 1. A safe work procedure has been developed and instituted for performing this work. 2. The hazards of pinch points will be covered with the injured employee, and a slide/tape training pro gram covering pinch points found in instrument work -- 131 -- CMA 048845 will be prepared for use in training all instrument men. CASE HISTORY NO. 2050 Chlorine Pump Description A chlorine pump was removed to maintenance shop for electrical repair. After flush cleaning and disman tling the pump, an electrician opened a cable connection bos adjacent to the stator of the pump motor. Gaseous chlorine was released under pressure. The box cover and chlorine struck the employee's face. Skin and eye bums resulted. Cause: 1. A hairline crack in the tube of the stator had allowed liquid chlorine to get into the stator housing. Pressure resulted when ambient temperatures were reached. 2. Cover splash goggles should have been worn in prefer ence to safety glasses. 3. The "breaking into lines and equipment" safety pro cedures does not adequately cover the type of work involved with particular reference to removing equip ment to maintenance shops for repair. Preventive Measures: Improve safe working procedures to cov er this type activity, including statement regarding necessar\ safety equipment (eye protection). CASE HISTORY NO. 2051 Chlorine Release Description A chlorine railroad tank car had been tested by pressuring up to 150 psi. After the pressure testing had been completed, the air was bled off by venting it to a boiler stack. The loading of liquid chlorine was started after the tank car had all the air bled off. Approximately three hours after the loading of the tank car had started, the rupture disc on the drop-out tank to the boiler stack blew and liquid chlorine was being discharged from the pipe above the rup ture disc. The shift foreman who was called to the scene discovered that the sniff valve on the line, the drop-out tank, and the boiler stack had not been completely closed prior to pumping chlorine into the tank car, and this allowed liquid chlorine into the sniff system. Several employees inhaled small amounts of chlorine, but none were serious enough to cause a disabling injury. Further investigation revealed that the panel alarm on the drop-out tank failed to operate and did not indicate that there was liquid chlorine in the drop-out tank. Preventive Measures: 1. A special meeting to review proper loading procedures and the seriousness of the incident with operating people was held. 2. Replace the rupture disc on the drop-out tank with a safety valve. ?. Replace the alarm on the drop-out tank with a pres sure-type alarm instead of a level-type alarm. 4. Review the controls and alarms on the sniff system. CASE HISTORY NO. 2052 Acetic Anhydride Pump Description An operator received serious bums to his eyes when acetic anhydride sprayed from the packing gland of the acetic anhydride pump. Due to chronic pressure build-up in the acetic acid charge line, a standard procedure for opening the valves on the line in a definite sequence was estab lished to relieve the build-up pressure into the reactor before starting the acetic anhydride pump. The valves were to be opened starting at the entrance to the reactor and continu ing to the valves on either side of the on-line meter and finally, opening the valves on the discharge and suction lines of the transfer pump, A 20,000 gallon tank car was being used as the storage vessel for the acetic anhydride and the valves at the pump near it were kept dosed as a safety measure in case the tank car was bumped or removed without proper disconnection. Also, pressure build-up in the line caused leaking problems at the pump seal so the pump was isolated by closing the valves on suction and discharge lines to minimize dripping of acetic anhydride in the pump area. As the operator prepared to pump acetic anhydride, he began opening the valves in the acetic anhydride line but inadvertently failed to open the valve immediately at the reactor so the pressure in the line was not released. He walked to the far end of the line to open the valves at the pump. As he reached for the valve on the discharge side of the pump, he stood directly in front of the packing gland of the pump and bent over slightly to pull the waisthigh valve handle towards him. As soon as he began to open the valve, acetic anhydride sprayed up and out from around the packing gland soaking his clothes and striking his face and eyes. The operator immediately leaned against the valve to close it and stood under the safety shower which was located ten feet from the pump. He washed out his mouth and nose so he could breathe and washed his eyes under the safety shower for an estimated four minutes. He was wearing standard safety glasses at the time of the incident. The operator ran to the change room where he removed his clothes, took a shower and washed his eyes for ten minutes with the help of his chief operator. He then went to the first aid station and used eye wash in both eyes. The operator returned to his work and finished the final 1 Vi hour of his shift and went home at 11:15 PM, He or his chief operator did not seek any further medical assistance at that time. The next morning (Saturday) the operator called the chief operator on duty and reported that his eyes were hurting. He was given the telephone number of the plant physician but was unable to receive treatment from the regular plant physician because his office was closed. The operator went to an emergency room at a nearby hospital for treatment of chemical bums to both eyes. Cause: Unsafe method. Preventive Measures: 1. A plant-wide audit of the acid and caustic storage and feed systems will be done and a report with recom mendations for pump and flange guards will be issued. Installation of recommended safety equipment will -132- CMA 048646 be completed as rapidly as such equipment can be obtained. 2. The results of this investigation will be reviewed with all plant operating personnel at the next regular safety meeting. 3. An improved system for assuring that prompt medical attention for injuries is available and used by injured personnel will be established. CASE HISTORY NO. 2053 Lead Azide Explosion Description: A chemist in a research facility sustained seri ous injuries to one hand and both eyes (he had just removed his safety glasses) which resulted in 35 days of lost time when he attempted to transfer 4.5 grams of lead azide which he had dried, into a blackened bottle. In his preliminary work with azides he had prepared and worked with a 0.5 gram of silver azide in solution and had encountered no problems. For the next step he prepared 4.5 grams each of silver azide and lead azide which he decided to isolate in the dry state so that he could subsequently add them in known amounts to other compounds. The materials were pre- pitated, filtered and washed in a Buchner funnel, transferd to watch glasses and placed in a vacuum dessicator in his hood. After four days, the material appeared dry and he decided to transfer the compounds to black painted bottles. The silver azide was successfully transferred from the watch glass to one bottle. As the chemist was about to transfer the lead azide to a similar bottle, it detonated when his spatula touched the watch glass. The immediate availability of highly trained first aiders who stopped the profuse bleeding before the arrival of the ambulance demonstrated the benefits of emergency team training. Preventive Measures: Most inorganic azides are extremely dangerous to prepare as there is always some possibility of explosion. For this reason, it is recommended that work be done with small quantities. Since the explosions occur more readily when the compounds are dry, it is advantageous to keep the material in liquid and protected from light. Lead azide, however, has been known to explode in solution. The warning above appeared in the text of the article which the chemist was following and makes a specific men tion of "small quantities." However, to be truly effective, a quantity limitation should be specific either in weight or volume. Investigation of this accident tends to confirm the validity of the following safety guidelines: 1. Experimental work involving azides should be restricted to quantities under 50 milligrams. 2. All work with azides should be performed behind shielding with mandatory use of personnel protective devices including gloves, safety glasses and face shields. CASE HISTORY NO. 2054 Welder Severely Burned Description, In the maintenance shop of a small plant, they had a metal covered bench that was used for welding opera tions . A vise was mounted on this bench and the maintenance man had the bucket elevator clamped in the vise while he was making repairs with an electric arc welder. The bucket, the vise and the bench top were all grounded through the lead to the welding machine. There was a rectangular, one gallon, metal can of paint thinner sitting on this bench. It is believed that the welding rod accidentally touched this can and an arc was struck. The can ruptured, threw solvent over the man's clothing, and was ignited. The resulting bums were severe over the middle and lower portions of his body. Preventive Measures: 1. Flammable or combustible liquids or gases should not be in the vicinity of welding operations. 2. A handy, safe place to hang or store the electrode holder should be provided so the operator does not have to keep this in his hand while making arrange ments. CASE HISTORY NO. 2055 Inadequate Knowledge of System Description: Employee's legs were sprayed with 9891 sul furic acid from a pump drain while he was returning the pump to service after repairs. Acid under high pressure was admitted to pump casing when the employee removed "danger" tags and restored air pressure to two air-actuated valves in the pump suction piping. He was unaware that controls in the central control room were set to open the acid valves when air pressure was restored; he had planned to make a visual inspection before opening these valves. Cause. Deficient written procedure outlining requirements when power-operated valves are used for isolation. Preventive Measures: Lock-and-tag procedure has been revised to outline special steps to be followed when poweroperated valves are used for isolation. CASE HISTORY NO. 2056 Maintenance Description: The injured employee had removed the red tags from pump valves and opened a valve in a seal purge line. Seconds later seal fluid dripped on the ground because the sample valve was found open and some droplets hit employee's high winter boots. As he is an experienced operator, employee closed the sample valve and was ready to change his shoes, when somebody turned his attention to a severe leak in an overhead line. In spite of wearing safety glasses, he got traces of leaking product in his left eye and rushed to the eye wash station. Later he was taken to the oculist who released him back to the plant after inves- -- 133-- CMA 048847 tigation. After returning to the plant the employee washed his feet thoroughly and changed his shoes. The next morning both feet were covered with blisters and he reported to the Medical Department when he arrived at work in the afternoon. Cause1. Red tug was forgotten on open sample valve 2. Inadequate preparation and check-in of pump valving prior to opening the seal purge line. 3. Failure to report for medical attention at first sign of injury. Preventive Measures: 1. Recommend the use of rubber boots. 2. Repeat proper red tag procedure. 3. Relocate operator to a plant not handling epichlorohydrin. CASE HISTORY NO. 2057 Plugged Line -- Operator Burned Description: Operator and trainee were filling a vessel with boiling process liquor, when the line plugged. The operator steamed the line to clear it which caused the filling hose to fly out of the pot, spraying hot liquor on the trainee, resulting in the bums. Cause: Employee was not given proper instruction on clear ing lines. The area was extremely confined and the hose was not secured. Preventive Measures: Line clearing procedures will be improved. Hoses will be secured, and a convenient exit prepared. CASE HISTORY NO. 2058 Oxygen Deficiency Meters Description: A new- instrument is available which sounds an alarm when the amount of oxygen in the air gets too low. It is suggested that these should be used on all vessel entry jobs. Difficulties have been experienced with manufac ture of the instrument but it is now available from Draeger Normalair, price Tb75. There have been comments that if a vessel is isolated from all sources of danger and if the atmosphere is analysed and shown to be o.k. before the entry permit is issued, then it is impossible for the oxygen concentration to get too low. Why then do we need oxygen deficiency meters? Our company has experienced several incidents in which the impossible happened and the oxygen content was found to be low. (a) The atmosphere was tested by aspirating a sample .through an analysis instrument. There was a blockage in Jthe instrument so no sample passed through it. A bubbler should have been fitted. (b) A sample was taken near a man-hole instead of in the middle of the vessel. (c) Two men working inside a tank complained of fUrT)e Their supervisor told them to connect up a compressed hose but they connected up a nitrogen hose by mistake (d) An "air"-drjven light was used to illuminate a vessel As a man was about to enter the vessel he noticed that the light was connected to the nitrogen supply. (e) A pit was dug in an old factory where acid is handled The atmosphere was sweetened with compressed air and tests carried out. Soon afterwards a man went into the pjt but felt unwell and came out. It was found that there was 129c carbon dioxide in the pit. Acid had soaked out of the ground and had reacted with limestone in the soil t0 produce carbon dioxide. In all these cases somebody was wide-awake and spotted the mistake before anyone was seriously hurt, but can we be sure that the impossible will not happen again and if it does, will we spot it in time? 1 therefore urge that each Works should obtain a number of portable oxygen alarms and that it should become the normal practice to carry one when entering a vessel or similar confined space. The detector is the size of a packet of cigarettes and makes a noise if the oxygen content falls. To test it, just breathe on it. -- From a U.K. Publication. EDITOR'S NOTE: The Draeger oxygen deficiency alarm mentioned in Acci dent Case History No. 2058 is available from Draeger Safety Limited, North Hyde Road, Hayes, Middlesex, England CASE HISTORY NO. 2059 Epichlorohydrin Burns Through Leather Boots Description: Two construction employees were called out to remove a manway from a tank. The production shift foreman explained the job and issued a safe work permit. Recollection is that the protective equipment was specified to the extent that "rubber gloves and boots" were required, but misunderstanding or interpretation of the boot require ment resulted in the employees wearing leather boots. As the plate covering the manway was loosened, a small amount of tank contents (epichlorohydrin) ran out and evidently got on one employee's boots. Later he noticed his boots were wet and washed them off with a hose nearby. On the way home he felt his feet begin to sting a little. When he got home he washed his feet thoroughly with medicated soap and they stopped stinging. When he awoke the next morning his feet were red, blistered and swollen. He reported to a hospital. Employee suffered chemical bums and infec tion. Cause: 1. Inadequate instructions by both contractor and plant supervisor. Employee was not made fully aware of the nature of chemicals involved; what to do in the event of exposure and specifically what protective equipment was required. 2. Failure to follow proper procedure when exposed to hazardous chemical. 3. Delay in securing proper treatment. -- 134-- CMA 048848 entive Measures; . Immediate consultations with all plant shift foremen and unit supervisors to point out deficiencies and that assumption must be made concerning new people in block that they do not know the hazards of the job involved and must be fully informed. . Monitor the workmen to be sure they are working safely and wearing proper protective equipment. 3 . Construction supervision to adequately instruct their employees in safety before delivering them to job site. CASE HISTORY NO. 2060 Machine Guarding Description: The injured was removing raw material from the hopper of a molding machine. When the discharge of material was completed, he saw that there was some left and used his right index finger to remove the balance, with out making sure that the machine was not in operation. In that precise moment the machine operator closed the gate and the new' cycle was initiated. When as part of the cycle, the feeding part moved, it severed about one third of the distal phalange of his right index finger. Cause, Lack of guarding. 1. Lack of a w ritten procedure for the cleaning of hoppers and feeding mechanisms. 2. Machine without a guard in the discharge orifice of the hopper. 3. Two people executing operations in one machine with out the proper coordination. 4 Unsafe act of the injured, since he performed the operation while the machine was working. Preventive Measures: 1. Solicit from maintenance the fabrication and installa tion of an exterior discharge for the hoppers that will make it impossible for people to put their fingers into the loader in this machine or similar ones. 2 Make a written procedure for cleaning hoppers and loaders for all machines and distribute to all personnel in the department. CASE HISTORY NO. 2061 Lockout Description: A machine operator was emptying vinyl regrind from the reclaim system. When the regrind stopped falling from the dump chute, a jam in the air lock system was indicated. He then opened the hatch above the air lock and allowed some of the material to flow out. He could see the material bridged in the throat. Not having anything handy, he reached into the throat with his hand to push material free. When pushing down on the material he icountered no resistance and his hand went down into Rr rotating vanes of the air lock. The first joint of the ng finger on his right hand was amputated. Cause: Primary cause of the accident was the operator's failure to lockout the equipment before attempting to unjam the material. A secondary cause was the operator's impulse to use his hand to unjam the material. A contributing factor to the accident was the tendency for material to repeatedly bridge in the throat of the air lock. Preventive Measures' 1. A separate lockout be installed for each Cumberland Air Lock. Present system must be locked out at the panel which also shuts off the grinder. The new lock out switch should not be able to be overridden by the high level bindacator. 2. An unjamming rod be hung by each air lock. This rod to be permanently attached by a chain to assure availability when needed. 3. Repair and/or replace damaged lead in chutes to the air locks. These have been dented by operators in their attempts to free jammed materials. 4. Install signs "Lockout Equipment Before Attempting to Unjam'' on all hatch covers. CASE HISTORY NO. 2062 Acid Transfer Description. Two operators were engaged in filling a Winchester with 98% sulphuric acid from the suction line of a transfer pump. One, the injured, was operating the audeo valve cock on the 2" line while the other was holding an 8 oz. sample jar below the outlet to receive the acid prior to transferring it, via a plastic tundish (funnel), into the Winchester. Both men were wearing rubber gloves and safety spectacles. During the course of filling, the gloves of the operator who was holding the jar had become con taminated with liquid and when pouring acid from the sample jar into the tundish the jar slipped from his hand, falling about 3" to the dwarf bund wall. Acid spurted from the neck of the jar when it struck the wall and a spot penetrated underneath the other's spectacles entering his left eye. He was transferred to the hospital for examination and treat ment. There was no permanent eye damage. The safety shower near the off-ioading point had been severely con taminated by a rupture in the hydrogen peroxide pipeline only a few hours before this incident and had been taken out of service for decontamination. A second shower was, however, available and located about fifteen yards inside the plant. Cause: Failure to follow instructions. The system for obtain ing sulphuric acid for use in this process had been in opera tion for about one month. Initially, it was a temporary measure anticipated to be in use for approximately one week. Normally a plastic container measuring IVi" x 4" x 4'' had been used to receive the acid from the line. This con tainer rested upon the floor of the tank farm during filling, and positioned immediately below the flange of the outlet. An 8 oz. sample jar was being used on this occasion as the plastic container was missing. preventive Measures: 1. The filling of any container with sulphuric acid by the existing method will be discontinued and an approved system introduced. -- 135 -- CMA 048849 2. The possibility of direct purchase in appropriate con tainers will be investigated. 3. There will be plant-wide publicity on the personal protective equipment required for handling corrosive liquids. CASE HISTORY NO. 2063 Xylene Line Maintenance Description: The injured was assigned to repair a leaking bottom valve. The necessary precautions were taken before breaking into the line, therefore, it was supposed that the line was empty. While removing the bolts of the valve, xylene sprayed into his eyes and onto his face. The injured was brought to the first-aid and to the hospital, where he had to stay for one day for observation. Cause: For flushing purposes a 1/2" xylene line is tied into the discharge line. The valve on this xylene line is always kept closed except for flushing. The line was drained and cleaned with steam. The additional personal protective equipment was specified on the permit: The injured had to wear a face-shield and neoprene gloves. The injured signed the permit without reading it. It was the third permit he received that morning. The injured did not know that xylene could come into the line. He did not know what xylene was. The xylene entered the line, because valve #2 was leaking. In the ``line-breaking procedure" it is mentioned that goggles should always be worn when breaking into a line. The investigating committee reported the following causes. 1. The leaking valve of the xylene line, 2. Failure to read the permit carefully and to wear the required additional personal protective equipment. 3. Lack of communication between the chief operator and the injured Preventive Mensures: 1. Emphasize plant-wide that goggles must be worn whenever breaking into lines, as mentioned in the procedure. 2. Emphasize the need for reading the work permits before signing. 3. Inform all maintenance personnel about the dangerous products used in the different units. CASE HISTORY NO. 2064 Acid Burn Description Water not getting to a deionizer. Supervisor and area operator were checking the system to find the problem. An automatic valve was not functioning properly. The supervisor was standing on a step ladder and the injured employee was standing at the base of the ladder. The super sor grasped an adjacent 1" acid line for added support. The acid line broke at a tee, spraying acid onto the boots of the supervisor and resulting in the bums on the operator's face and neck. Preventive Measures: Line has been replaced, and angje iron used under the line as a support. Employees have been instructed to close the valve at the storage tank so the line will drain, and therefore be empty most of the time. CASE HISTORY NO. 2065 Hydrofluoric Acid Burns Description: Process man took sample of hydrofluoric acid using a plastic bottle and wearing prescribed rubber gloves He later carried the sample bottle to the laboratory wearing a cotton work glove. The cap did not fit tightly on the bottle, resulting in acid leaking out and saturating his cloth glove. He continued to wear the saturated glove until he noticed a burning sensation on his fingers. Cause: Failure to follow a safety rule and wear the prescribed rubber glove when handling acid samples. Preventive Measures: Employee has been re-instructed about the importance of using the proper glove and the plant safety rules have been reviewed with all employees. CASE HISTORY NO. 2066 Hopper Description: Employee was attempting to dump trash hopper by pushing the release lever with the palm of his right hand. In order to apply more force, he placed his left hand on the lift truck fork. When the hopper dumped, his left little finger was caught between the fork and the hopper mounting frame. Employee received a severe laceration to the tip of his left little finger, necessitating surgical amputation. Cause: 1. The cable attachment was broken off the dump lever, requiring the employee to place his hand directly on the lever. 2. Employee used improper procedure for dumping trash hopper. 3. Placing hand in unsafe position. 4. Failure to provide written procedure for this job. Preventive Measures: 1. Replace all broken or missing release cables on this and other hoppers, 2. Provide hook rods to enable operators to dump hop pers remotely. 3. Provide written job procedures and retrain employees on this job. CASE HISTORY NO. 2067 Boiler Furnace Description: Employee was cutting clinker from boiler fur nace with high pressure water. Part of clinker fell and forced hot gas, water or steam out of manway and burned employee. - 136- CMA 048850 Xuuse Working through too large an opening in the furnace. *re\ entire Measures: 1. Design a closure to decrease the size of the opening. 2. Use air-cooled insulated suit. CASE HISTORY NO. 2068 Exploding Bottle of Acid Description: Two employees were injured when a nine liter bottle ot concentrated sulfuric acid, with which they were working, exploded. Both employees suffered severe acid burns on the lower portions of their bodies and legs. One employee also suffered a broken right hip. The two employees were attempting to transfer a mixture of sulfuric acid and silver sulfate from a nine liter bottle to a burette. They were having difficulties making the transfer, so they decided to apply pressure by means of a rubber aspirator into the air space above the solution. The aspirator method was unsuccessful. The bottle was then moved to a shelf (its ultimate location), about three feet above the work table. Once again the aspirator method was tried, again it was unsuccessful. They then decided to apply plant nitrogen (pressure 75 psi gauge) to the bottle. This was accomplished by butting a piece of Tygon tubing against the opening in the nozzle of the aspirator bulb. In order to use this method, it was necessary for one employee to stand on the laboratory table. They were able k get some acid to flow. This procedure was repeated. Kt some point in this operation the bottle of acid and silver sulfate mixture exploded, shattering completely, and spray ing the mixture on the lower portions of the bodies of both men. Both men were severely burned and one fractured his hip when he tell from the laboratory table. The two men were not wearing protective equipment other than safety glasses. It is estimated that one employee will lose six weeks and the other four months. Pre\ entire Measures: 1 The use of compressed gases as a source of pressure in transferring liquids from or into glass containers will be prohibited. 2. Protective safety equipment will be used while work ing with acids. 3. Concentrated chemical solutions will not be permitted above laboratory table level. 4. Fundamental principles of handling chemicals safely will be reviewed with all laboratory1 personnel. CASE HISTORY NO. 2069 Ladder Description: A millwright fell from a ladder and suffered brasions to both knees, lacerations on his forehead and (L'e along with a fractured left wrist as a result of a combinaon of his not following his supervisor's work instructions and the unsafe use of a stepladder. Reconstruction of the incident showed the man had been taken to an area where a motor for an automatic door operator had to be removed and he had been so instructed by his supervisor. However, as he went ahead with the task he proceeded to remove the motor and the gear drive as a unit (105 lbs) and as he uncoupled the whole mechanism he dropped it onto the top step of his stepladder; the ladder slid away from the wall and crashed to the floor taking him and the door operator along. It is possible he could have taken down the whole operator mechanism without accident, but his improper use of the stepladder, leaning it against the wall instead of open ing the legs, allowed the extra weight to push out the bottom of the unsupported ladder and cause the fall. Preventive Measures: Remedial action by the Plant Engi neering Department included their scheduling sessions on the use of a programmed instruction training meeting on ladder safety for all members of that department Lost time has been estimated at 60 days. CASE HISTORY NO. 2070 Caustic Leak Description: A caustic leak at an operating pad dropped ma terial onto a Nelex line heat tracing, causing it to deteriorate to the point where an arc occurred, presenting a potential ignition source for the flammables that are handled in the area. A "still" beeper alarm brought the on-site firemen to the scene and three attach lines were laid into the area as a precaution while the electrical system was de-energized. These hose lines were later used by the firemen to flush the caustic from the spill area and damages were confined to the loss of heater tracing. Cause: Investigation revealed the caustic had come from a dram valve that was unintentionally left open and to prevent a recurrence a hose has been connected to the caustic drain line. It should also be mentioned the heat tracing involved was properly installed and fused, and the circuit breaker had tripped when the arc occurred. CASE HISTORY NO. 2071 Ultraviolet Burns Description: A sterile filler operator suffered ultraviolet burns of both eyes as a result of exposure at a filling machine due to a protective shield being out of place and the injured not wearing the required protective goggles. Since this inci dent it has been proposed a limit switch be placed on the protective shield to prevent the machine from operating while it is out of position and the special eyewear provided must be worn by the operators. Lost time amounted to six days. CASE HISTORY NO. 2072 Truck Loading Description: Construction work in a truck loading area required a tanker to be spotted out of its usual slot and after the operator hooked up the charge hose he fell from 137- CMA 048851 the truck while reaching for the nearby pump switch. The truck, being out of its usual spot, necessitated the operator to reach out further than usual to activate the switch and as he did he lost his balance and fell off the truck catwalk into an open ditch. Sutures were required to close a head laceration and a fractured skull kept him at the hospital for three days observ ation. Total lost time has been estimated at 32 days Prevent!i e Measures Corrective action taken following this incident includes placing the pump switch and a chain oper ated valve adjacent to each other and the traffic department is to look into the type of catwalks being placed on tank trucks. CASE HISTORY NO. 2073 Unloading Chute Description: A welder was involved in an accident resulting in five transverse fractures of the vertebrae. He was pre paring to fit a plate on a large telescoping unloading chute which was free to pivot. The chute which was inadequately secured swung into the welder, pinning him between the chute and a large round drive shaft. Cause: The work was being performed under emergency `'Hurry up and get done" conditions without adequate plan ning. Preventive Measures: 1. The chute will be secured so that it cannot move. 2. The design of the chute is being changed to prevent it from binding. CASE HISTORY NO. 2074 Oxygen Hose Rupture Desci iption Employee had changed out the oxygen cylinder and was opening the cylinder valve. When his co-worker lit the welding torch, the oxygen hose ruptured at the regula tory and burned the employee under his left arm. Cause: 1. Used improper procedure to change out oxygen cylinder. 2. Signaled co-worker to light torch before oxygen cylin der valve was fully open. Preventive Measures- Retrain employees on proper proce dures. CASE HISTORY NO. 2075 Unloading Propane Description: Employee was attempting to connect the cus tomer's hose to truck pump to offload propane into cus tomer's storage tanks. The customer's hose w;as equipped with a 90 0 tum quick-opening ball valve and was liquid propane full. He placed the hose across the frame of ^ truck and bent the hose 180 0 to make the pump connection The hose slipped from his hands and the valve handle struck the truck frame and partially opened. Propane from thy hose sprayed the employee in the groin area, causing fjrst and second degree burns. Cause: 1. Customer's hose was equipped with a 90 0 tum quick opening valve. Use of a ball valve without a handle lock device presents a hazard as any mishandling of the hose could cause the valve to open. 2. Employee was not thoroughly familiar with pump truck equipment. Pump discharge connections are located on both sides of the truck, making it unneces sary to place hose across frame and handle it in the awkward fashion described, 3. Employee was not wearing prescribed personal pro tective equipment (apron, gloves, goggles). Preventive Measures: 1. Review- of AUL safety operating procedures is in progress with driver technicians. 2. Pump connections have been labeled. Will request all locations using 90 0 ball valves to provide handle lock or replace the valves with LPG globe valves. 3. Existing procedures specify use of apron, gloves and goggles for pump loads only. Procedures will be expanded to require this personal protective equipment for all cargo transfers. CASE HISTORY NO. 2076 Machinery Description: The injured employee, while setting a packag ing machine, tried to adjust a glass bottle without stopping the machine. He caught two fingers between moving parts of the equipment, smashing them. Two months later surgery was required, which resulted in permanent impairment of function of the distal phalange of the middle finger, right hand. Cause: 1. Moving part not guarded. 2. Operator did not stop machine before adjusting glass bottle. Preventive Measures: Special guard installed. CASE HISTORY NO. 2077 Drain Valve Description: The operator was discharging excess 3.5 kg/cm2 steam to the atmosphere using the muffler. Upon opening of the vent valve, hot condensate was blown out of the muffler and soaked the operator. The operator received extensive first and some second degree burns on back, arms, and legs. - 138- CMA 48852 attse: 1. Operator omitted to open drain valve to ensure that no condensate was trapped in the muffler. 2 Drain valve of muffler was installed so that access W'as difficult. Prewntive Xleaswcs: 1 Drain valve was relocated for easier access. 2. All mufflers were reviewed to prevent recurrence. 3, All operating personnel was instructed in the hazards of using steam systems, where hot condensate may be trapped. CASE HISTORY NO. 2078 Sulfuric Acid Hose Description: Employee blocked in an air supply valve on a hose which was hooked up to the bottom of a filter used to purge a sulfuric system prior to making a tie-in. The acid in a low spot in the system drained into the air hose overnight. He closed the valve on the bottom of the filter and air supply but was called to do another job before dis connecting the hose. The next day he noticed the hose was still connected and decided to disconnect and roll it up. As he disconnected the hose from the filter, sulfuric acid sprayed from the connection causing first and second degree burns to face, neck, right hand and forearm. Apparently the air supply valve leaked through sufficiently to pressure ^he hose. Cause: 1. No means to bleed the air from the hose. 2. Purge should be attached to a high spot in the system rather than a low' spot. 3. Lack of continuity in completing job. 4. Improper protective equipment. Employee had on monogoggles but was not wearing full acid suit which is required for this type work. Preventive Measures: 1. Insist on proper protective clothing when opening lines or equipment in corrosive service. 2. Add additional alarms, safety shower and eye wash fountains. 3. Instruct all employees in the proper method of washing off chemicals. CASE HISTORY NO. 2079 Power Supply Description A power failure, affecting several production units, occurred when a pole crossarm was twisted around its center support bolt. One or more of the incoming 14.4 kv wires contacted the overhead static wire support angle bracket attached to the pole. )Cause: Use of crossarm as an anchor point for sheave, 7k cable pulling operation was under way. The subcontractor doing the work had attached a rope pulley directly to the crossarm. Excess tension on ropes pulling the cable pulled the crossarm loose from its braces. Preventive Measures: 1. Attach sheave directlv to pole rather than crossarm. OR 2. Provide union in conduit at pole base to avoid need tor "pull" around right angle at base of pole. CASE HISTORY NO. 2080 Phenol Unloading Description: The current shortage of chemicals created a situation which resulted in a non-employee being splashed with phenol on the right foot, both legs, right forearm and hand, The situation was created when phenol was delivered in a 4,000 gallon tank trailer, from a new vendor, instead of a rail car from the usual source. The phenol unloading station consisted of a swing arm approximately 15 feet above ground which could be con nected to the dip tube located on top of the rail car. To unload the tank trailer, a flexible pipe was connected to the swing arm and then to the truck's bottom-unloading valve. This meant that the phenol had to be pumped up hill. When the tank trailer was empty, the compressed air from the tank trailer was used to blow' the remaining phenol out the hose line system. But because of the up-hill system and the air gurgling through the liquid phenol, the hose line system did not clear completely. At the time of the accident all valves had been shut before the tank trailer operator opened the coupling between the unloading station and the tank trailer. But because the cou pling was the lowest point in the system, the uncleared phe nol ran back down the hose and splashed the operator as he made the disconnect. Since he was wearing only gloves and eye protection (safety glasses), a very serious accident was avoided by the quick reaction of a second person who immediately removed the operator's trousers and began washing the phenol off the operator with a water hose. By the time the ambulance arrived a short time later, the operator was being bathed in warm water. He was treated in the Medical Department and sent to the hospital for further observation. Cause: The accident situation was caused when the piping system between the unloading station and the tank trailer was temporarily modified in a manner that allowed a small backflow when disconnected. This occurred because deliv eries of phenol were being made via tank trailer and not as usual by rail car. Preventive Measures: When the delivery' and unloading of chemicals is not done in its usual manner, the handling procedures should be carefully analyzed for possible hazard ous conditions. A Process Safety Review is recommended. When handling highly toxic chemicals, proper protective clothing should be worn. Each handler should be absolutely certain of the proper emergency action to be taken in case of contact. -139- CMA 048853 CASE HISTORY NO. 2081 Welding Description: A welder was injured when an oxygen hose on a burning outfit blew up due to a back flash from a burning torch. He suffered a mild concussion from the explo sion and will probably lose five days from work, The cell tear down maintenance crew consisting of six men was preparing to tear out cel! A35, Two men were on the scaffold preparing to bum off the lower skirt bolts, one was standing at the base of the scaffold and the injured and another man were at the burning outfit tanks. The injured was adjusting the oxygen pressure on the gauge. He com pleted the adjustment and apparently said, "okay". His coworker opened the torch and struck the lighter. The torch lit and simultaneously there was a loud explosion. The in jured, who was standing about two feet from the tanks, was seen to stagger back and fall to the floor. He was taken to the dispensary and transferred to the hospital via ambulance. He was semi-conscious when brought into the dispensary. The only obvious injury was a small abrasion on his chin. He was holding the right side of his head and rather incoherently complaining of pain in his head and cars. At the hospital he said he did not know what happened. He said the last thing he could remember was setting the pressure on the oxygen gauge at 35 or 40 psi. Cause- An extensive investigation was conducted by the cell maintenance supervisors, and the safety supervisor. The torch, gauges and hose were removed from the tanks and examined. The gauge showed no evidence of damage, the oxygen hose showed evidence of burning where it rup tured at the gauge connection. There was also some carbon on the gauge connection. The hose was cut. split and examined. There were traces of carbon in the hose about one foot from the torch end but very little if any within six inches of the rupture site. The cause of the accident was obviously a flash-back through the torch and the oxygen hose. The hose ruptured at its weakest point, i.e. where the regulator fitting is crimped on the hose. Had the gauge blown the employee could have been seriously, if not fatally, injured by flying metal fragments. The question that remained was: How did the acetylene get into the oxygen side of the torch? The torch and the gauge were examined by the supplier of oxygen and acetylene who also repairs and reconditions torches and gauges. The regulator was undamaged but will be reconditioned. Upon examining the torch it was deter mined that the burning tip was faulty, there was a flat spot on the oxygen blocs pipe seat. This could allow acetylene into the oxygen side of the torch provided there was no pressure on the oxygen side. Within 48 hours the injured employee was discharged from the hospital. When again questioned he said the wrench was missing from the acetylene tank and the tank was opened with a pair of channel lock pliers. He was asked if the jpxygen was on and he said the tank was probably on but ahe gauge was not set because he set the gauge when his partner said he did not have any oxygen. From his descrip tion of the sequence ot events it is obvious how the acetylene could get into the oxygen side of the torch with a faulty tip and the acetylene side pressurized. The injured said he was looking for the acetylene cylinder wrench in the outfit tool tray when the hose blew, This would put hie head approximately one foot or less from the hose when it blew. Preventive Measures: Management personnel have discus sed the findings of the investigation and the following action is being taken. Check valves have been purchased and in stalled on all burning torches on the acetylene and oxygen connections. All welders and burners will be reinstructed in the proper procedure to follow when hooking up oxygen and acetylene equipment to bum or weld. Only the welder or burner assigned to the job will open the tanks and adjust his regulators to the desired pressure. CASE HISTORY NO. 2082 Disposal of Sodium Waste Description. The shift supervisor was requested by his group leader to dispose of a small amount (estimated two to four inches in the bottom of a five-gallon pail) of dried sodium dispersion by burning. This dispersion had been stored in the sodium drum area in excess of two years. The container had been opened earlier in the day and the contents observed visually by several employees, including the shift supervisor and group leader. At 8 PM, accompanied by another employee, the supervisor proceeded to dispose of the dis persion. Without removing the container from the transite storage shed, he opened it preparatory to adding alkalate prior to burning. (NOTE: Rain had been falling but at the time of opening the container there was only a slight mist in the air.) Upon opening the container the dispersion exploded, spewing the supervisor about the head and shoul ders with sodium and residual solvent. There was immediate ignition. The employee removed the supervisor from the fire area immediately out into an open drive area and pro ceeded to extinguish the flames which engulfed his head, shoulders and arms. He was assisted in this by two other employees who had procured a fire blanket. Meanwhile, cold water via a hose was doused over the supervisor's head, minimizing the burns. His clothing was removed and he was covered with the blanket and taken to first aid. The police, fire department, and life squad were called and responded within ten minutes. The supervisor's upper extremities were packed with wet ice and he was then trans ported to the hospital for treatment. One employee suffered slight second degree bums to the thumb on his left hand in extinguishing the flames which engulfed the supervisor. It is believed that when the container was opened, moisture entered it touching off the sodium. (NOTE: The two involved men were wearing safety glasses but were not wearing equipment prescribed for such an operation (goggles or face shield, gloves, etc,).) There was no property damage. Preventive Measures 1, Safety is a prime responsibility of supervision. In this case supervision did not make sure that proper safety equipment and precautions were to be used in carrying out the assignment. Supervisors will be advised that they must assume and discharge properly this critical responsibility. - 140- CMA 048854 2. Long time casual storage of hazardous chemicals is particularly dangerous, This practice is to be dis continued and the complete laboratory will be reviewed to assure compliance. 3. Employees are to be cautioned that short cuts are not to be taken. Proper safety practice is always to be followed. In this case the supervisor neglected to gel properly prepared to carry out the assignment even though he is highly experienced. 4. Sodium and sodium dispersions, lithium, potassium, etc. are extremely unstable in the presence of moisture and must be treated accordingly. Exposure to moisture engendered by inclement weather is to be avoided. 5. When a project is terminated it should be discontinued in its entirety including draining and flushing or destroying all chemicals and dismantling of equip ment. 6. Disposal of hazardous chemicals will be made only in the presence of, and under the supervision of. the safety advisor. 7. Routine safety inspections are to be made by all department heads to make certain that storage of hazardous chemicals and materials is controlled to an absolute minimum. CASE HISTORY NO. 2083 CASE HISTORY NO. 2084 Eruption -- Steam Stripping Description: Using standard equipment and procedure, the employee was steam stripping a latex, which he had been doing daily for over a year. The operation appeared normal until the end when it was noticed that the top layer (monomer) of the condensate (collected in a graduated cylinder) appeared cloudy. The employee removed the con tainer and peered into it to examine the cloudy layer. The contents erupted into his face. Although he was wearing safety glasses, the employee received a severe thermal bum to the left eye. Cause: 1. Employee exposed himself to hazardous situation without adequate protection. 2. The event of a run-a way polymerization in the conden sate flask was not anticipated or protected against. Preventive Measures: 1. Condensate collecting flask will be cooled and chemi cally inhibited. 2. Use of chemical goggles when working with hazard ous chemicals will be mandatory. Drumming Caustic wscnption: Employee was loading molten caustic into a Ieries of drums. Drumming operation requires the drum lid be placed loosely in position after the filled drum is moved from under the loading spout and the next drum to be filled is in position. Normal work procedure had allowed this to be done as the next drum was filling. Operator location and controls are well protected, but placing the lid in position requires stepping from behind the shield. Apparently the operator lowered the fill spout but did not hit the hole in top of drum. The fill spout has a limit switch but the dome shaped drum top probably allowed limit switch to be energized and the pump motor switch turned on. As the operator stepped from behind the shield, molten caustic struck him on left side of face and neck. He was wearing chemical goggles but suffered multiple thermal bums to face and neck. Cause 1 -. Operator apparently began filling when the spout was not in drum. 2. Operator could move from behind shield while caustic was pumping -- job procedure did not prohibit. 3. It was not required that face shields be worn when installing lid. Preventive Measures: 1. Correct job procedure to instruct operators not to move from behind the shield at any time when pump is running. 2. Require face shield anytime operators step out from behind the shield to install lid. 3. Develop equipment to automatically or remotely put lids on drums. 4. Install equipment to automatically stop pumping when operator moves from behind the shield. CASE HISTORY NO. 2085 Static Ignition of Flammable Vapors Description: The operator emptied a fiber lined tank which had contained 30% solution of methyl alcohol and water, with calcium tartrate precipitate. As usual, he started wash ing the tank with water, when a flash fire occurred, causing first degree bums to face and second degree bums to left hand and thumb of right hand. The fire immediately selfextinguished, lacking flammable vapors. Cause Either rubber hose or synthetic working cloth caused spark with static charged vessel lining, that ignited residual flammable vapors. Preventive Measures: 1. Plastic lining discarded. 2. Rubber hose grounded. 3. Working cloths replaced with non-synthetic fabric type. CASE HISTORY NO. 2086 Pump Maintenance Description: The injured employee (an operator) was help ing a fellow' employee close a six-inch ball valve on the suction of a pump. The valve had not been operated for quite some time and was stuck; so to accomplish the job, a 24-inch pipe wrench and a cheater were being used. The wrench slipped, causing one of the men to lose his balance and fall backward to the ground. He caught himself with his hands and started to get back up. As he turned his foot for better positioning, he felt an immediate sharp pain -141- CMA. 048855 in his left ankle and fell backward again, unable to support his weight. He had fractured two bones in the left leg above the ankle. Cause: 1 VaKe was difficult to operate through lack of use over an extended period. 2. Using pipe wrench on T-handle of six-inch ball valve to gain added leverate. Preventive Measures: 1. Specially built valve handles are to be used on all salves of this manufacture where the manufacturer's handle is inadequate. 2. A plant survey has been made to identify and locate other valves where pipe wrenches, cheaters, or other unsafe practices are being used for operation so they can be corrected or eliminated. 7. Lack of appreciation of the critical relationship 0f process variables in the region of maximum exotherm Preventive Measures: 1. Redesign the building to open construction. 2. Better definition and documentation of process safetv technology before scale-up or transfer of a process", 3. More extensive use of automatic control systems on pilot plant process equipment. 4. Provide emergency procedures for each process operation. 5. Increase the priority, scope and depth of safety audits, emphasizing the extreme events and combination of events that could occur. CASE HISTORY NO. 2088 CASE HISTORY NO. 2087 Vinyl Acetate Polymerization Explosion Description: An explosion in a research laboratory resulted in a fatality when a technician on the opposite side of the building from the explosion was blown out with the wall from the third level. Six additional employees received medi cal attention for non-disabling injuries. The roof and three walls of the four-story, 102' x 62' building were destroyed and an adjoining two-story annex damaged. Equipment in the pilot plant suffered little damage. A solution polymerization of vinyl acetate in toluene was being carried out under reflux at atmospheric pressure in a 2.000-gallon glass-lined reactor. The exothermic reaction at the start of polymerization became faster than expected and the vent lines, condenser and jacket cooling were unable to handle the increased heat and foam generated. The pres sure built up with a resulting further increase in temperature and reaction rate. The pressure caused premature gasket failure on the condenser, resulting in leakage of some quan tity (gallons) of vinyl acetate and toluene inside the building. The 50 psi rupture disc blew', venting most of the reactor contents to the atmosphere but immediately afterwards the vapors in the building ignited and the building exploded resulting in the fatality and damage mentioned above. The process had been operated on this scale at another location for 11 batches and once in a different facility four days before the accident. Eruption from Heated Caustic Car Description: The employee was attempting to unload a 50T caustic tank car which had been heated due to low ambient temperatures. When the bottom hookup was made, he was wearing safety glasses, monogoggles and a face shield, plus a lab coat, rubber boots and rubber gloves. He started the pump and climbed to the top of the car and opened the dome vent. Caustic under pressure sprayed 20 to 25 feet up the side of the building and blew his goggles and glasses off. He received bums to the left eye, face, mouth, lips and right arm. Cause: 1. The car appears to have been overfilled, 2. The tank car was not vented when heat was applied, 3. Thawing was not part of normal operation because normally ears are still warm and heat is not required. Preventive Measures: 1. Full rubber suit protection shall be enforced. 2. Revise the operating instruction to include opening of the vent before any heat is applied to the car. CASE HISTORY NO. 2089 Ketoximes and Ketoximosilanes Cause: The investigation team thoroughly studied the chemical, physical, procedural and administrative aspects of the cause of the accident. No single factor can be isolated as the sole cause of the accident but the interrelated contribut ing factors were identified. These are: 1. Increased reaction rate resulting from unforeseen effects of nitrogen blanket. 2. Excessive foaming and its effect on heat removal capability. 3. The design of condenser vent line. 4. Lack of predetermined or automatic "shortstop'' procedures. 5. Composition of gasket in the condenser. 6. Use of 50 psi rupture disc. Description: An explosion took place in a pilot unit convert ing methyl ethyl ketoxime to its silane derivative as indicated: Et 3 C = NOH+ RSiCb Me acid Et tor" RSi(ON = C' )3 Me + hydrochloride salt of the acid acceptor Specifically a glass receiver ruptured, even though vented. Fragments of glass were found throughout the area. There was no fire and no one was injured as the unit was unattended at the time. -142- CMA. 048856 Cause: 1. It was discovered that a substantial excess of RSiCL had been added to the unit due to operator error. This led to hot acidic conditions in the vessel that ruptured violently, 2. Research studies uncovered the fact the ketoximes and their derivatives, such as the silanes, can undergo highly exothermic, acid-catalysed degradation with rapid liberation of gaseous by-products. It is hypothe sized that this phenomenon is associated with the clas sical Beckmann Rearrangement whereby the consid erable energy associated with the carbon-nitrogen dou ble bond is released. If concentrations of acid salts of ketoximes and/or their silane derivatives are high, exothermic degrada tion can be initiated as low as 50-70 C. A Lewis Acid. FeCL, in concentrations of> 500 ppm can also cause initiation at approximately 100 C, of the runaway exotherm. Preventive Measures: The unit was re-engineered to provide concentrations and temperature control with provisions for monitoring conditions. Automatic emergency shutdown was provided if imbalances or heat build-up occur, CASE HISTORY NO. 2090 Hydrogen Cyanide Release description- A pressure gauge failed on an HCN pump pischarge line resulting in a release of hazardous material. On the morning of the incident, two pipefitters and a tank car unloader assigned to pipe up a tank car of hydrogen cyanide for unloading into the storage tank. When they approached the tank farm, they detected an odor which they recognized as hydrogen cyanide (HCN). They notified the building operator and the department supervisor. Two of the men put on Scott Air Paks and rubber suits to inves tigate the problem. They first shut off the recirculating pump which had been running all night, cooling the HCN tank. Cooling the HCN tank preparatory to unloading an HCN tank car is a normal procedure. Liquid was observed dripping near the top of the HCN storage tank. A mound of ice (about 18" high) present at the top of the tank was not immediately recognized as froz.en HCN. The men proceeded to locate the source of the dripping HCN by removing some piping insulation. They traced the leak to a pressure gauge and then replaced it. The pressure gauge shut-off hand valve was also replaced as a precautionary measure. Three members of the HCN emergency team, appeared on the scene about 9:00 AM, and assisted in coordinating cleanup activities and advising plant supervision of the HCN problem. Cleanup of the spill was undertaken. This involved melt ing the HCN ice mound by hosing it down with water and neutralizing the water in the dike enclosing the HCN tank by adding sodium hypochlorite. Monitoring the sur rounding area for HCN and the sewer for chlorine resulting when the sodium hypochlorite/HCN solution was pumped to the sewer was carried out. Three samplings of HCN dike water yielded reading over 300 ppm. Sodium hypochlorite was added to the water until HCN readings fell below 100 ppm. The neutralized HCN dike water was then pumped to the plant sewer system. After the spill, estimated at 50-100 gallons, was cleaned up. one man who was slightly nauseous, reported to the dispensary where he was given amyl nitrite treatment. Cause: Equipment failure due to use of improper material of construction. Preventive Measures. 1. Replace all pressure gauges on HCN and acrolein storage and handling systems with 316 S.S. dia phragm type pressure gauges. Eliminate any unnecessary gauges. 2. Install a special sounding alarm horn in the HCN/acrolein area to warn people away from the area in the event of an accident. 3. Once the special HCN "Keep Away" alarm has been installed, always turn in an alarm when any type of HCN emergency occurs. 4. Install bright colored luminescent tape on HCN/acrolein fence to better draw attention to the hazardous area and install larger, brighter signs. 5. Review the necessity of increasing the frequency of inspection of the HCN area. 6. Evaluate the need and feasibility of pressure testing all HCN lines. 7. Provide improved lighting at the HCN unloading dock. 8. Re-evaluate an automatic HCN leak detector and alarm for monitoring storage area, 9. Add note to operations and emergency manuals that an HCN leak can freeze and form icicles and mounds of ice. 10. Stock at least three all 316 S.S. diaphragm type pressure gauges in stores. Install L x 2' plastic signs at all HCN/acrolein storage and weigh tanks. Signs to read: Caution -- Use Only 316 S.S Valves. Piping and Pressure Gauges in this Area. 11. Remove obsolete Scott Air Pak (one) at HCN tank. Evaluate need for replacement. 12. Review incident with all plant personnel stressing the importance of using proper materials of construc tion. CASE HISTORY NO. 2091 Opening Tank Dome Description: Shipping operator was opening the dome cover of a muriatic acid tank truck. As he loosened the bolts holding the cover, pressure in the tank blew the lid away from the opening and acid fumes blew into the operator's face and eyes. He was wearing safety glasses. Cause: Employee failed to read the pressure gauge on the tank before attempting to open the cover, and he also failed to vent the truck through the line which was provided. Train ing had not been adequate. Preventive Measures: Employees will be given additional training in the safe procedure and carefully instructed not to open any vessel until pressure has been relieved. -- 143 -- CMA 048857 CASE HISTORY NO. 2092 CASE HISTORY NO. 2095 Crane Conveyor Belt Description A new electrode was being raised into position using an overhead crane. The electrode was longer than normal -- in order to raise it to a sufficient height, the supervisor operating the crane had to override the safety cut-oft switch. After bypassing the limit switch, he pressed the up travel button to get sufficient height to position the electrode, and when he released the button the crane failed to stop. He quickly depressed the down travel button, but this was ineffective. He then used the emergency stop button, cutting off all power. By this time the block was into the drum. Description: Operator noticed the conveyor belt was running to one side on the tail pulley, and he attempted to alio^ the belt by throwing fine material between the bottom of the belt and the top of the belt idler. After throwing the fine material, he leaned over the belt to check the alignmenthe attempted to support his body's weight with his right hand, and his hand slipped and was caught between the belt and an idler. A second man heard him call and pulled the emergency stop cable located alongside of the belt. He suffered a fractured finger and abrasions on the back of the hand. Cause: 1. Longer than normal electrode which could not be handled under the normal procedure. 2. Malfunction on the crane hoist switch. Pre i entire Meas ures: 1. The crane lifting hook has been redesigned so as to get two more inches of clearance. 2. A limit switch has been installed which cuts off the power 12" below the drum that cannot be overridden. 3. A positive stop-start button has been installed which will cut off all power. 4. The electrode manufacturer will supply shorter elec trodes in the future. CASE HISTORY NO. 2093 Hydrofluoric Acid Burns Description: Process man was taking a sample, and as he applied pressure to a valve the nipple to which the valve was attached broke, and he was splashed with acid. Cause: Nipple was corroded thin, but the corrosion was not obvious. Preventive Measures: Heavy duty nipple has been installed and employees have been instructed to wear face shield and protective clothing when sampling for HF. CASE HISTORY NO. 2094 Loading Description: Operator was stepping from a tank trailer to the loading platform to disconnect a vapor hose. He grabbed hold of the swivel loading arm, and the arm swung out pushing him off the platform from w'hich he fell to the ground, a distance of approximately 8'. landing on his feet. There was no apparent injury. Cause: Trailer was parked improperly, and employee failed lb recognize the hazard. Preventive Measures: Loading line will be piped to ground level so that the danger of a fall will be eliminated. Cause: Employee performed an unsafe act and placed him self in a vulnerable position. Preventive Measures: All employees have been instructed not to throw fines on belts in order to align them. An emer gency stop cable has been installed along side of the tail pulley, and a guard has been placed at this location to prevent anyone from getting close to the roll. CASE HISTORY NO. 2096 Hot Tar Description: Operator received first and second degree bums to back and legs while loading a tar box with hot tars. As he walked up to the box to shut valve, hot tar suddenly blew out of the box. He turned and ran 60 feet to safety behind the dike. Tar spray stopped in less than 10 seconds; and operator then turned off process pump and valve, called for help, and got under safety shower. He had been wearing hard hat and chemical worker goggles. Cause: Trapped moisture in a pocket of frozen tar apparently vaporized when the tar melted and caused eruption. Preventive Measures: 1. Load tar boxes to one-third full and allow to set 30 minutes before proceeding to fill tar box. 2. After tar box is filled, clean and close the loading port to minimize potential for water entry. 3. Engineering studying ways to improve tar handling or possibly local tar burning. CASE HISTORY NO. 2097 Airline Mask Description: While attempting to bleed off liquid chlorine into drums of a caustic solution for neutralization, a chemical operator removed his airline mask when his hose knotted -- causing his air supply to stop -- and he was exposed to a small amount of chlorine gas that was in the area. Cause: Review of the incident showed that two nearby air masks had previously been used and in preparing to enter the chlorine area he only prepared enough hose to reach -144- CMA 048858 where he needed to go. In performing his work he must : stretched the hose in such a way that it crimped -- ting off the air supply. Treatment was given at Plant Health and the nearby hospital and he is presently under the care of an outside physician. Lost time has been estimated at nine days. /Yruvimr Measures - Remedial action included a recom mendation on better inspection procedures for air mask sta tions and consideration to limiting entry into hazardous areas only when self-contained breathing apparatus is worn. On this latter item, the use of an airline mask to enter a hazardous area is ill advised m view of the fact that any number of things can happen to knot or otherwise cut off your air supply because of the hose's vulnerability as it trains behind. Cause: A review of the incident showed the draining of chlorine into drums of caustic is a standard practice and in this incident he had opened the valve very slowly; how ever, a blockage in the line apparently prevented the initial flow and as he opened the valve wider a surge of material suddenly came through, causing the caustic to splash out of the drum. Since this incident a work order has been issued to fabricate and install a shield at this caustic drum to prevent a recurrence of such an incident. Lost time amounted to two days. CASE HISTORY NO. 2101 Laboratory Explosion CASE HISTORY NO. 2098 Toluene -- Eye Burns Description: A chemical operator suffered chemical bums to both eyes when he was sprayed by a toluene solution. At the time the operator was blowing down an iron filter when the toluene pump was activated and spray from a loose flange resulted. The operator at the time was carrying protective goggles but did not put them on while trying to get by the toluene spray in his efforts to leave the work area. Lost time from this injury amounted to five days and is considered to have been preventable in view1 of the fact that this particular flange was recently worked on by a mechanic but was not properly tightened before returning it to service. CASE HISTORY NO. 2099 Tank Truck Spotting Description. A materials handler received sulfuric acid burns of his face when a tank truck was being spotted and some material sloshed out of the tank's open top manhole as the truck was moved into position. Cause: A review of circumstances that led to this injury revealed that a control sample was taken earlier and the top hatch was not closed after that was completed. Since this incident the two departments concerned have established a safe procedure that should prevent a recurrence. Lost time amounted to two days. Description: While preparing a reagent solution which con sisted of a mixture of p-dimethylaminobenzaldehyde in sul furic acid, the flask exploded in his hand, exposing the technician to acid bums of the eyes and hands. Cause: Reconstruction of the incident indicated the techni cian had begun not with the normal dilute sulfuric acid but with concentrated acid and in adding the powdered material he used a small amount of water to aid in the transfer. When the ingredients were put together he immediately stoppered the one liter flask and began shaking. It exploded within a few seconds. Fortunately the injured (with the help of a fellow worker) reached the eye wash station, where he quickly and adequately flushed his face and eyes. From this investigation it has been concluded that there are two possible reasons to account for this explosion. First and most probable is the addition of water to the concentrated acid resulting in considerable heat generation. The second reason is a possible violent chemical reaction that occurred between the reagent powder and the concentrated acid. It should be mentioned here that the pro cedure of adding the powder to the concentrated acid and then diluting later was not standard practice. Preventive Measures: As a result of this incident the labora tory area has been requested to review its practice or pos sibly modify and enforce the present eye protection pro gram for the area. It is felt that this injury may not have been completely averted if the standard safety glasses were worn, but these would have helped protect the em ployee's eyes. Lost time amounted to three days. CASE HISTORY NO. 2102 Sewer Exposure CASE HISTORY NO. 2100 austic Splash 'escription: A chemical operator suffered chemical burns of the face, neck and back when he was splashed by some caustic solution that was being used to neutralize chlorine vapors from a line that was being drained. Description: While working on a project involving the main chemical sewer, two outside contractor's employees were exposed to ah unknown waste material in the vicinity of an excavated opening in the pipe. Acute reaction in one man was minor, the other fell unconscious. Mouth-to-mouth resuscitation was administered by a fellow employee while awaiting response by a plant nurse. Both men were trans ported to a local hospital where they recovered in a short time and were released. -- 145-- CMA 048859 Cause: From a description of the events, it appears that a chemical or an in-situ reaction product within the waste stream arrived in their work area as a black frothy sludge. Analysis of test samples taken after the sludge had passed was unable to identify the responsible agent. Hydrogen sul fide, however, is strongly suspected. CASE HISTORY NO. 2103 Vent Stack Description: Two maintenance employees were removing a corroded vent stack from the roof of a reactor building. The vent stack had been tied to an adjacent vent, and the injured employee proceeded to cut the stack using a chisel and hammer. After four or five blows the stack broke and kicked out at the break, striking the mechanic's forearm and thigh. He suffered a severe laceration of the left forearm and bruised his thigh. Cause: Failure to secure pipe properly before starting removal. Preventive Measures: Vent stack has been replaced with one made of stainless steel to help minimize corrosion and a crane will be used on any similar job in the future. CASE HISTORY NO. 2104 Reactor Cleaning Description: Laborer was removing scrapings and chunks of material from reactor. He was holding a large piece with his left hand and using an axe with his right hand in order to break up the chunk. His left hand slipped into the path of the axe blade, resulting in the injury. He suffered severe laceration of the knuckle of the middle finger of his left hand and damage to the tendon. CASE HISTORY NO. 2105 Hose Connection Description: There is a 3/4 inch washout nozzle with a hose connection located on the drain line of the caustic evaporator. When the drain line plugs with salt, a condensate hose is connected to the nozzle and the line is back-flushed with condensate. Employee, who had just completed this operation, disconnected the condensate hose from the hose connection without first closing the valve on the washout nozzle. Hot 20c7r caustic sprayed through the open valve, striking him on the hips, arms and face. will be modified for use as an evaporator drain. The drain now in service will be used only during plan[ shutdown. This will eliminate the need to wash the drain line each time the evaporator is cleaned. 2. Bleed lines will be installed on all evaporator dram washout nozzles. 3. Each process supervisor will ensure that his area is in compliance with he Divtsion Safety Policy on hose connections. 4. Each process supervisor will modify all bleed lines on double block and bleeds in his area so that they cannot be used as hose connections. CASE HISTORY NO. 2106 Blending Powder Description: Employee had been blending powder by remote operation. He entered the room while the blending bowl was still running, apparently to add binding solution. However, before he was able to add the binder, the blending bowl caught fire. The flaming ingredients were thrown about the room and upon the employee, who was standing directly in front of the bowl with the safety door open. His hands, face, chest and neck were exposed and received second degree bums. His eyes were protected by safety glasses and were not injured. Preventive Measures: Remotely stop blender before enter ing room where potentially dangerous materials are being mixed. CASE HISTORY NO. 2107 Oil Transfer Description: A chemical operator received first and second degree thermal bums to his left hand and leg when a tempo rary hose, being used to transfer hot oil, separated and splashed him. The temporary system referred to had been set up following a discovery' that oil in a vehicle makeup tank had been overcharged due to a malfunctioning auto matic fill valve and they were attempting to return the excess. Preventive Measures: Since this incident it has been decided to perform the following: 1. Repair the tank fill control system. 2. Install a permanent line to enable pumping back to the storage tank. 3. Repair the level alarm on the makeup tank. 4. Install a safety shower in this area. This latter item was considered desirable because there are no units in the immediate vicinity of this operation. Cause' 1. Disconnecting condensate hose without blocking valve to caustic line. 2. There was no means of depressuring the condensate hose before disconnecting. Preventive Measures: 1. The discharge drain on the caustic forwarding pumps CASE HISTORY NO. 2108 Lab Trash Bag Accident Description: A laboratory analyst sustained a serious lacera tion on the leg when a plastic trash can liner was being lifted out of the trash can. The plastic liner split allowing -146- CMA 048860 the contents, which was mostly broken glass, to spill out th a glass fragment striking the analyst's leg. Cause: Unsafe practice. The major contributing cause of the accident was the method of trash removal which required the analyst to lift out the plastic liner and place it at the outside trash pick-up point. Other factors arc: 1. Other trash materials thrown into the "glass waste" receptacle tend to camouflage the fact that the broken glass is present 2 Trash often accumulates faster than it is picked up which necessitates the removal from the lab by the analyst. Preventive Mensures: 1. Provide additional trash containers, with covers and handles. 2. Waste receptacles to be removed from the lab and emptied into trash truck by waste disposal contractor. 2. Provide receptacle for broken glass and label "Glass Only". 147- CMA 048861 INDEX This index has been compiled and organized to assist readers searching for accident case histories involving specific chemicals, specific pieces of equipment, or specific occupa tions. To find a case history of a particular nature, look first under the group category most closely associated, e.g.. Chemical, Operation or Occupation, Equipment. Explosions and Pressure Releases, Fires, Static Electricity, Waste Disposal, Corrosion, or Protective Equipment. The same accident case history may appear under several categories. For example, accident case history No. 660 appears under the ''Chemical" category as "acetaldehyde", under the "Operation or Occupation" category as "venting", and under the "Explosions and Pressure Releases" category as "acetaldehyde." Many accident case histones, particularly those involving occupations or equipment failure, are not easily identifiable and may appear under various listings. For example, a particular case history may be listed under "pipe" or "line" or perhaps "valve" or "gasket.' ' Similarly, a case history invol ving ` `hose failure' ' may appear under "loading'', "unloading" or "transfer" etc. For Accident Case Histories Nos. 1 to 596, see Volume One -- 1962 For Accident Case Histories Nos. 597 to 1097, see Volume Two -- 1966 For Accident Case Histories Nos. 1098 to 1623, see Volume Three -- 1970 CHEMICALS Acetaldehyde................................ 117, 586, 660, 911, 1764 Acetanilide ...........................................................................266 Acetic acid............................. 90, 306, 328, 765, 805, 920, 1000, 1011, 1305, 1525, 1609, 1664, 1865, 1912, 1985 Acetic anhydride..................................103, 463, 572, 1650, 1865, 1905, 2029, 2052 Acetic mix ............... Acetone ................... Acetone/Chloroform Acetone/Methanol.. Acetylene................. Acetylides................. Acrylic acid ............. Acrylamide............. Acrlvonitrile ............ ........................................................ 277 ............136, 435, 1 153, 1583, 1948 ...................................................... 1661 ....................................................... 1933 ....................... 657, 744, 1849, 1992 ............................................... 479, 571 ....................................................... 1759 ....................................................... 1977 234. 1214, 1452, 1897, 1906 1996 Adipic acid............. Alcohol................... Alcohol, denatured. ^^klkyd resin............. ^Jkllyl Alcohol......... Alum...................... Aluminum............ Aluminum/caustic ................................................ 44, 739 .................................... 136, 152, 506 ......................................................1205 ........................................................ 909 .........................................................150 ............................................ 656, 877 ................................ 849, 1312, 2021 .........................................1115, 1888 Aluminum isoperoxide......................................................1171 Aluminum nitrate................................................................1512 Americium.......................................................................... 1106 Aluminum paint.................................................................... 104 Aluminum paste..................................................................... 72 Aluminum triethyl............................................................... 819 Aluminum zinc...................................................................1722 Ammonia..................................57, 87, 125, 230, 231. 239, 279, 288, 297, 306, 366, 386, 394, 430, 466, 509, 518, 529. 536, 598, 685, 709. 763. 792, 806, 961, 933, 947, 951, 959, 978, 1021, 1610, 1114, 1219, 1247, 1447, 1691, 1695, 1757. 1846, 1965 Ammonium nitrate............................ 368, 873, 1325, 1454. 1483. 1495 Ammonium perchlorate ....................... 800, 845, 881, 992, 1002. 1768 Amyl acetate............................................................. 293 Aniline.....................................32, 1 13, 118, 140, 189. 602, 1161. 1908 Arsine ................................................................................... 1550 Asbestos................................................................................ 1628 Asphalt............. 1103,1689 -148 - CMA 048862 ^^ido compound. ^^wxite.................. Benzene.............. Benzene hexachloride Benzoic acid............... Benzoyl perodixc... Bisphenol-A............... Boron ......................... Boron nitrate............. Boron trifluoride....... Brine ........................... Bromide...................... Bromine...................... Bromochloromethane Butadiene.......... ....... Butanes....................... t-Butyl benzene....... Butyl ether................ Butyl peroxide......... .............................................. 880 ............................................... 319 ..43, 81, 120, 129. 267, 703, 823, 1141, 1335, 1565, 1627 ........................................120 ................................ 1223, 1486 ............................................... 996 .............................................1250 ............................................... 745 ............................................. 1334 ............................................. 1279 ............................................... 187 ............................................. 1834 .......197, 379, 675, 786, 826, 945, 1636, 1863 ............................................. 1999 ..................303, 790 ..................160, 537 ......................... 1886 ...................... 1020 17, 302, 579, 1914 Cadmium...............................................................................1573 Calcium chloride.......................................................... 69, 848 Calcium cyanide .................................................................. 521 Calcium hypochlorite............................428, 453, 663, 1216 Carbon casts............................. 774 ,arbon disulfide............................121, 124, 309, 515, 558, 613, 652, 971, 1181, 1861 Carbon monoxide.......................... 34, 280, 357, 548, 1023 Carbon tetrachloride............................................................ 427 Caro's acid.............................................................................662 Cast iron...............................................................................1536 Caustic .......................... 85, 100, 107, 133, 134, 146, 149, 169, 182, 185, 186, 188, 194, 214, 221, 261, 294, 312, 342, 392, 401, 425, 429, 436, 450, 480, 495, 498, 502, 506, 626, 631, 680, 693, 695, 702, 710, 769, 773, 809, 900, 902, 927, 1055, 1157, 1184, 1200, 1224, 1243, 1260, 1265, 1294, 1300, 1331, 1456, 1481, 1493, 1527, 1537, 1539, 1541, 1546, 1574, 1589, 1642, 1643, 1667, 1672, 1680, 1704, 1723, 1725, 1734, 1739, 1743, 1749, 1774, 1826, 1847, 1873, 1878. 1904, 2001, 2046, 2070, 2083, 2088, 2100 Celulose nitrate.......................................... 61, 304, 483, 514 Chlorine..................................86, 286, 310, 448, 488, 608, 623, 655, 692, 695, 707, 752, 754, 808, 868, 919, 955, 971, 1035, 1041, 1144, 1266, 1272, 1290, 1295, 1515, 1555, 1563, 1595, 1736, 1880, 1959, 1980, 2018, 2041, 2050, 2051 fhloroacetic acid........................................................122, 228 hlorobenzene....................................................................... 137 3hlorobutadiene................................... 200 Chloroform...........................................498, 693, 1686, 1913 Chloronitrotoluene............................................................... 907 Chlorosulfomc acid.......................................... 96, 642, 1835 Chlorothiazide....................................................................... 700 Chromic acid........................................................... 1919, 2009 Chromium dioxide/Pyridine............................................. 1284 Chromous chloride............................................................. 1660 Coal dust........................................................................33. 449 Coke........................................................................................ 504 Copper solution .............. 349 Cryogen................................................................................ 1156 Cumene hydroperoxide .......................................................906 Cuprous ammonium chloride.............................................861 Cyanamide.............................................................................329 Cyanide ....................................................................1148, 1270 Cyanoacetic acid...................................................................858 Cyanuric chloride................................................................ 1869 Cyclohexane.......................................................................... 128 Cyclohexylamine.......................................................444, 682 2,4-D....................................................................................... 713 Decaborane............................................................................. 749 Diborane................................................................................. 730 Dichloroacetylene...............................................................1989 Dichloromethane................................................................. 2020 Dichlorophenol..................................................................... 901 Difluoramine..........................................................................768 Dimethylamine.......................................................... 1673, 1682 Dimethylaniline................................................................... 1754 Dimethyl sulfate........................................................... 36, 1654 Dimethylsulfoxide...................................................1187, 1718 Dinitroaniline chloride....................................................... 1763 Dinitrofluoroethane.............................................................. 784 Dioxane...................................................................................610 Dodecyl benzene................................................................ 1548 Dust.....................................................618, 1634, 1746, 1815 Epichlorohydrin................................................................ ,2059 Epoxy................................................................................ ...1798 Epoxy (paint)....................................................................... 1681 Ether............................. 451, 516, 561, 616, 676, 782, 822 Ether peroxides..................................................................... 412 Ethyl acrylate........................................................................ 235 Ethyl acetate........................................................... 986, 2037 Ethyl alcohol.......................... 316, 1479, 1582, 1741, 1780 Ethyl chloride.........................................................................138 Ethyl isocyanate.................................................................... 677 Ethylamine, anhydrous......................................... 1022, 1292 Ethylene..................................................424, 580, 712. 1656 Ethylene diamine...................................................................563 Ethylene dioxyamine perchlorate.................................... 1622 Ethylene gylcol................................................................... 1789 Ethylene oxide.................... 479, 560, 571, 758, 792, 1666 Exhaust gases......................................................................1647 Ferrocene 1203 Fluorine............................................................................... 1089 Fluorochloro lubricants/aluminum...................... 1312. 1449 Foam rubber....................................................................... 395 Formaldehyde...................... 16, 213, 381, 706, 1319. 1322 Formic acid...................................................... 497, 554. 1273 -149- CMA. 048863 Fumaric acid........................................................................ 202 Furfury] alcohol...................................................................858 Gasoline....... Glue............... Glycol............ GKcolonitrile ...411, 535 .......... 1917 ......71, 464 1196, 1240 Halogenated solvents ........................................................1465 Hexane ........................................................1780, 1898, 2039 Hydrazine......................................................... 940, 983. 1893 Hydrazine nitroformate......................................................1010 Hydrochloric acid......................... 78. 770, 815, 918, 1119, 1604. 1775, 1852, 1972 Hydrocyanic acid................................ 234, 587, 1031,2090 Hvdrofluoric acid............................733, 1278, 1801, 1952, 2065, 2093 Hydrogen ............................. 347, 490, 505, 576, 609, 694, 723. 1097, 1098, 1297, 1485, 1586, 1916 Hydrogen chloride............................................................... 406 Hydrogen cyanide......................... 205, 238, 246, 459, 471, 896.903,1218,1710 Hydrogen fluoride.............................................................. 1605 Hydrogen, liquid ............................1001, 1238, 1257, 1474 Hydrogen peroxide................................ 127, 314, 393, 431, 562,979.1121,1626,1648 Hydrogen sulfide................................ 13. 54, 56, 207, 272, 335, 432, 467, 538, 802, 818, 854, 937, 1064, 1199, 1213, 1249, 1526, 1602, 1721, 1753, 1784, 1930 Igniter mix............................................................................1183 Isopropyl chloroformate....................................................... 145 Isopropyl ether.......................................................................603 Kerosene...............................................................................1217 Ketoximcs.............................................................................2089 Lead ..................................... Lead azide .......................... Lead styphnate................... Ligroin.................................. Lime..................................... Lithium................................ Lithium aluminum hydride ....................1306 949, 987, 2053 ..................... 957 ..................... 876 ....... 1138, 1851 ..................... 751 ....... 676, 1182, 1494, 1832 Magnesium perchlorate.......................................................243 Maleic anhydride................................... 622, 797, 817, 2032 Mastic..................................................................................... 220 Mercury.................................................................................. 481 Metal fumes.........................................................................1301 Metal, molten......................................................... 1698, 1800 Methacrylic acid ................................................... 291 454, 498, 627. 703,964. 1096, 1215, 1228, 1254,1298, 1337, 1443, 1506 ^^^fethyl acetylene .................................................................632 Methvl alcohol ..............................454, 498, 627, 703, 964, 1096, 1215, 1228, 1254, 1298, 1337, 1443. 1506. 1796, 1822, 1863, 1933. 2085 Methyl amyl alcohol ............ Methyl azide.......................... Methyl bromide.................... Methylaminobenzaldehyde... Methyl chloride...................... Methyl chloroform................ Methyl ethyl ketone............... Methyl methacrylate............. Methyl parathion................... Methyl vinyl ketone............. Methylamine .......................... Methylaminobenzaldehyde... Methylcydohexylamtne........ Methylene chloride................ Moisture sensitive.................. Mixed acid............................. Molten metal.......................... Monochloracetic acid............. Monochlorobenzene............... Monoethanolamine................ Morpholine sulfenyl chloride Mucochloric acid................... .............................. 335 .............................. 887 .............................. 746 ...........................2101 ......1074. 1471, 1876 ..............................1158 ..............................1478 .............................1601 ................... 371, 1562 ................... 260, 1528 ...................... 60, 1844 ......................... 2101 ...............................351 ....... 966, 1176, 1549 ..............................1125 ............491. 578, 925 ...................1263, 1467 ....... 728. 1024. 1708 .............................. 1487 .............................. 1523 .............................1806 .............................1186 Naphthalene..................................564, 565, 573, 596, 2042 Natural gas...............................................................499, 1061 Nickel/caustic........................................................................ 172 Nitrate, fertilizer................................................................. 1326 Nitrate/wood.........................................................................1581 Nitric acid ........................................82, 103, 112, 131, 174, 193,422, 853, 1 152, 1244, 1559, 1582, 1762, 1797, 1854, 1866, 1969 Nitric fumes...........................................................................217 Nitrile......................................................................................151 Nitroaniline..............................................................1624, 1657 Nitrobenzene...............................................................678, 944 Nitrobenzoyl chloride........................................................ 1915 Nitrocellulose........................................................................ 638 N t trochlorobenzene............................................................. 1624 Nitrocresol .............................................................................701 Nitrogen.................. ....324, 356, 720, 1056, 1059, 1775, 1870, 1963 Nitrogen oxides .... ......................... 287, 1903 Nitrogen peroxide.. ..................................... 128 Nitrogen trifluoride Nitroglycerin.......... .................................... 683 .567, 734, 844, 1102. 1615 Nitroso chloride.... ...........................................749 Nitrostyrene .......... .......................................... 1982 Nitrous fumes......... .......................................... 208 Oil..................................................................1811. 1990, 2107 Oleum................................................... 775. 835. 1246. 1441 Organic phosphate insecticide....................................... 1557 Oxalic acid...........................................................................839 Oxygen.......................... 39, 397, 500, 720, 824, 865, 953, 988. 1111, 1185, 1469, 1560, 1765, 1870, 1931, 2074 Paraformaldehyde.....................................................203, 1235 Paranitrometa cresol ......................................................... *649 Paranitro phenetole...... .........402 150- CMK 048864 athion...............................................................................1894 laborane........................................................................... 750 entol ........................................................................... 363 Peracetic acid ......................................................... 1795, 1804 Perchlorate........................................................599. 766. 1124 Perchloric acid................................................ 581. 799. 1308 Perlite..................................................................................... 801 Peroxides................................... 202, 476. 852, 1043, 1693, Petroleum naphtha ...........................1..7..1..3... ...1..7..3. 17(4a8) Phenacetin................ ............................................ 759 Phenobarbitol.......... ............................................ 389 Phenol....................... .45. 92, 278, 292. 399, 522, 607, 689, 752, 790, 1018, 1571, 1639. 1646, 1706, 1776, 1882, 2080 Phenol formaldehyde ...... Phenyl mercuric acetate.. ...................................1633 ................................ 666 Phenylhydrazine............... ......................................137 Phosgene............................ Phosphate ester................ 1127, 1277, 1552, 1658 ..................................... 524 Phosphine.......................... ..................................1066 Phosphoric acid ............... .........58, 391, 601, 851, 962, 1046 Phosphorus ....................... ....... 215, 232, 468, 840 Phosphorus oxychloride.. ................ 433, 520, 555. 1067, 1274 Phosphorus pentachloride ..................................... 593 isphorus trichloride ... ..................................... 445 halic anhydride.......... .........................718, 1036 Pitch................................... ...................... 1255, 1524 Platinic oxide.................... ...................................1580 Plutonium......................... ..1053, 1188, 1211, 1212 Plutonium nitrate.......... ......................................1498 Polyethylene................... ........................................ 700 Polvsulphide................... ........................................766 Polyvinyl chloride ......... ........................................ 960 Potassium......................... .........................1154, 1891 Potassium compounds... ........................................ 743 Potassium dichromate.... ..................................... 1583 Potassium hydroxide .... .........318, 597, 920, 1712 Potassium nitrate............ Potassium permanganate Potassium tert-butoxide.. ........................................ 745 ..................................... 1842 ......................................1718 Propadiene ...................... ........................................ 632 Propane............................. Propyl alcohol................. ......630, 879, 1944,, 2075 .....................................1248 Propylene oxide............. ................................ 31, 758 Radioactive waste............................................................. 1716 Raney nickel catalyst....................................................... 1225 Resin................................... 240, 255, 343, 963, 1558, 1633 Rosin .................................................................173, 871, 1338 ^^Safety" solvent ^Blicylaldehyde.. ^Talt. molten......... Shock sensitive.. Silicate solution. Silieo manganese .........442 .........527 ......1095 .721, 820 ....... 1875 ....... 1535 Silver....................................................................................... 695 Silver, fulminate of.............................................................. 976 Silver nitrate..........................................................................740 Silver oxide.......................................................................... 1048 Silvering solution...............................................................1733 Soda ash............................................................ 162, 421, 1964 Sodium...................................... 68, 99, 132, 565, 781, 878. 1201, 1566, 1620. 1653, 2082 Sodium amide .............................. 762 Sodium azide....................................................................... 1957 Sodium bisulfite................ ....................................... 183. 1164 Sodium bromate.................................................................... 874 Sodium chlorate.....................................55, 282, 1979, 2019 Sodium chlorite..................................................................... 839 Sodium cyanide....................................................................648 Sodium fluoride...................................................................1050 Sodium hydride........................................................ 969, 1587 Sodium hydrosulfide.......................................................... 1753 Sodium hydrosulfite............................................................ 350 Sodium isopropylate .......................................................... 1017 Sodium MBT..................................................................... 2032 Sodium methylate.................................................................693 Sodium nitrite.........................................................................183 Sodium peroxide.................................................................. 646 Sodium sulfate.......................................................................212 Sodium sulfhydrate......................................................13, 1064 Sodium thiocyanate.............................................................. 568 Silicon tetrachloride............................................................460,465 Steam................................ 41, 178, 708, 1679, 1724, 1756, 1773, 1814, 1920, 1967, 2010 Styrene......................................................... 41, 281, 674, 832 Sulfur............................. 27, 251, 649, 863, 934, 935, 938, 1027. 1139, 1521, 1629, 1784, 1895, 1995 Sulfur chloride............................................................. 130, 690 Sulfur dioxide.................................... 926, 932, 1044, 1140, 1178, 1803, 1910 Sulfuric acid.......................... 25, 67, 76, 83, 88, 135, 149, 244, 333, 358, 376, 512, 531, 557, 604. 760, 764, 813, 828, 888, 956, 967, 972, 977, 982, 984, 1012, 1194, 1496, 1533, 1572, 1625, 1668, 1810, 1877, 1945, 1983, 2000, 2014, 2023, 2026, 2055, 2062, 2068, 2078, 2099 Tar............................... Tetraethyl lead.......... Tetrafluoroethylene... Tetrafl uoroh ydrazine Tetrahydrofuran......... Thiocyanate............... Thionyl chloride....... Titanium carbide...... Titanium chloride__ Tollen's reagent....... Toluene...................... Toluene disocyanate . Tricalcium phosphate Trichloroethanol....... Trichloroethylene... . .....................................1725, 2096 .................................................. 241 ................................................. 1520 .................................................. 683 ..................................................... 77 .................................................. 853 ................................................ 1808 ..................................................618 .................................................. 477 .................................................. 714 141, 688, 699, 742, 886, 1195, 1285, 1532, 1685, 2098 ................................................. 1332 ................................................. 1242 ................................................. 1574 ......................52, 495, 575, 1977 -151- CMA 048865 Trichlorophenyl hydrazine.................................................. 627 Triethylamine....................................................................793 Trinitrotoluene.................................................................... 1289 Trioxane................................................................................ 1129 Ultra violet......... Uranium.............. p-Urazine ......... Urea peroxide.... 179, 1128, 2071 ........ 1104, 1296 .................... 144 ...................... 719 Vinylacetate ................................................. 384,661,2087 Vinyl hutyral...................... ...................................................643 Vinyl chloride.....................................625,816, 1113, 1132, 1551, 1802, 1818, 1932, 2033 Vinyl cyanide............................................................. 262, 364 Vinylidine............... Vinylidine chloride Viscose.................... ........ 1879 110, 1172 ............ 26 Water, hot .......................................................................... 1637 Wax ................................................................ 870. 1630, 1705 X-Ray...................................................................... 1611, 1828 Xylol....................... 91. 383. 492, 748, 1593, 1617, 1966, 2063 Zinc ........................................................................................ 557 Zinc chloride............................................................. 84 Zirconium............................................................................. 1234 Zirconium/niobium.............................................................1545 OPERATION OR OCCUPATION Acidation...............................................................................1930 Agitation....................................................................1881, 1968 Bagging .................................................................... 1209, 1517 Blending................................................................................. 403 Boiler inspection...................................................................922 Burning pit................................................................. 1207, 1208 Casting.................................................................................... 849 Centrifuging.......................... Ill, 127, 212, 759, 781, 785 Charging reactor................................... 867, 964, 994, 1624 Chlorination..................................286, 371,445, 488, 1144 Chromatography.................................................................... 592 Construction ...................................................... 636, 761, 891 Cooling......................................................................... 372, 453 Diazotization....................................................................... 1763 Distillation............................184, 241, 291, 311, 320. 431, 590, 616, 640, 677, 678, 782, 784, 822, 1195, 1898, 1900 Drumming.......................... 1106, 1153, 1171, 1273, 1287, 1305, 1309, 1314, 1524, 1743, 1764, 1808, 1952, 2083 Drying................................................................................... 1683 Dust extraction.................................................................... 1815 Electrical..................................788, 860, 1060, 1245, 1258, 1313, 1328, 1569, 1578, 1590, 1594, 1597, 1782, 1825 Electrostatic precipitation.................................................... 344 Etching.................................................................................... 917 Ether extraction .................................................................... 272 Fire drill................................................................................ 1039 Flaking caustic.................................................................... 1200 Flame testing....................................................................... 1124 Fluorination..............................................................1045, 1089 Fractination..................................................................363, 838 Fleat curing............................................................................ 290 Hopper cleaning................................................................. 1130 Hydroblasting......................................................................1713 Hydrogenation.................................................................... 1659 Hydrostatic testing.................................................... 323, 856 Inerting.................................................................................... 679 Inspection............................................................................11539 Lead burning..................................................................70, 197 Loading................................ 162, 298, 306, 314, 384, 386, 450, 529, 572, 602, 604, 652, 752, 835, 927, 939, 1021, 1096, 1152, 1331, 1447, 1563, 1606, 1642, 1706, 1757, 1844, 1876, 1878, 1902, 1910. 1944, 1963, 1994, 2007, 2014. 2026, 2072 Lock and tag.......................... 58, 152, 161, 221, 398, 434, 531, 811,981, 1006, 1015, 1271, 1468, 1530, 1543, 1592, 1612, 1813, 1909, 1943, 1946, 2040, 2061 Maintenance............................. 56, 95, 100, 107, 121, 124, 169, 194, 196, 200, 208, 209, 217, 263, 312, 317, 324, 337, 341, 342, 392, 401, 406, 419, 438, 440, 481, 502, 580, 1088, 1109, 1112, 1117, 1147, 1150, 1167, 1178, 1184, 1220, 1231, 1244, 1252, 1264, 1295, 1300, 1306, 1440, 1441, 1453, 1462, 1481, 1515, 1542, 1551, 1555, 1567, 1591, 1631, 1636, 1639, 1703, 1727, 1737, 1755, 1799, 1803, 1805, 1820, 1851, 1855, 1873, 1937, 1945, 1954, 1962, 1967, 2036, 2049, 2055, 2056, 2063, 2086 Materials handling..................................................1841, 1918 Melting............................................................. 139, 735, 1883 Methylation.......................................................................... 1786 Mixing................................... 277, 278, 345, 494, 766, 772, 881, 909, 949, 1050 Molding................................................................................... 110 Grinding................................................................................ 1692 Neutralization...................................................................... 1691 --152-- CMA 048866 ^kration............................. 103, 128, 569. 578, 925, 1311, A 1489, 1499, 1854 Pickling................................................................................... 193 Pilot plant ....................................................... 117, 664, 1907 Pipe fitting................................ 80, 96, 159, 205, 282, 441, 546, 712. 736, 762, 786, 795, 813, 826, 847, 873, 894.912, 921, 936,938, 977, 985, 1054, 1135, 1614, 2016 Pipetting................................................................................ 1824 Polymerization................................................................... .1649 Pressure testing............................. 356, 395, 496, 914, 970, 1761. 1810, 1906 Process reaction....................... 69, 71, 144, 150, 173, 183, 206, 213, 254, 274, 283, 329. 335, 343, 350, 379, 387. 421,423, 424, 428, 455, 479, 490, 505. 516, 517, 521, 526, 541, 555, 557, 560, 562, 567, 588, 598, 680, 694, 701, 706, 707, 745. 748, 758, 790, 802, 906, 1083, 1113, 1243, 1260, 1293, 1329, 1456, 1500, 1557, 1559, 1613, 1670, 1688, 1741, 1771, 1911(a), 1932, 1964 Pumping.......................................... 88, 187, 410, 568, 1042 Purging ...................................... 273, 367, 843, 1765. 1775, 2042, 2044 Recovery, acid ....................................................................888 lvage......................................................................... 122, 436 Sampling...............................160. 257, 264, 333, 355, 642, 895, 903, 982, 1000, 1009, 1020, 1031, 1090, 1142, 1190, 1256, 1272, 1280, 1571, 1707, 1726, 1809, 1882 Sand blasting........................................................................ 629 Shutdown .................................................................1151, 1270 Startup...................................................................... 1877, 1974 Steaming..................................41, 102, 178, 332, 404, 444, 649, 708, 710, 739, 783, 797, 809, 817, 834, 846, 848, 850, 869, 872, 900, 902, 904, 961, 989, 1029, 1064, 1160, 1204, 1544, 2077, 2084 Storage ......................................................... 1759, 1792, 2034 Sulfonation.......................................................................... 944 Tank cleaning..................................................................... 1627 Tank entry...............................52, 207, 360, 416, 432. 442, 501, 634, 667, 691, 753, 761, 794. 855, 866, 899, 973, 1033, 1057, 1061, 1126, 1185, 1213,1227, 1235, 1262, 1451, 1457, 1459, 1509, 1522,1549, 1553, 1575, 1635, 1644, 1740, 1818, 2030 Transfer................................ 83, 90, 91, 99, 137, 148, 182, 232, 289, 300, 349, 391, 405, 429, 473, 498, 728, 742, 824, 826, 827, 828, 875, 883, 889, 928, 930, 1036, 1085, 1192, 1194, 1246, 1255, 1322, 1330,1474, 1507, 1532, 1690, 1749, 1793, 1865, 1901, 1904, 1938, 1972 Unloading..................................27, 43, 214, 235, 239, 251, 281. 310, 319, 374, 394, 433, 497, 512, 536, 554, 564, 573, 596, 597, 644, 661, 682, 685, 688, 690, 699, 700, 760, 770, 929, 933, 935, 978, 986, 1011, 1027,1114, 1140, 1294, 1317, 1338, 1471, 1514, 1601,1629, 1630, 1694, 1695, 1705, 1739, 1753, 1754,1798, 1835, 1843, 1847, 1861, 1875, 1995, 2080, 2088, 2094, 2100 Venting............. ..................... 660, 1019, 1501, 1665, 1762 Water blasting.....................................................................1890 Welding............................44, 80, 105, 114. 145, 166, 198, 284, 316, 322, 359, 362, 474, 493, 500, 513, 528, 780, 831,905, 1141, 1205, 1277, 1301, 1336, 1473, 1490, 1525, 1641, 1664, 1700, 1742, 1885, 1935, 2013, 2081 Windstorm.......................................................................... 1323 Working alone ................................................................... 1556 EQUIPMENT Acid bottle................................................................... 375, 556 Acid bucket........................................................................... 443 Aerosol can.......................................................................... 1241 Agitator................................ 124, 329, 511, 578, 588, 666, 1176,1217,1291.1452,1968 Air line.................................................... Air line mask............................................................ 360, 1719 Air pressure .................................... 1099, 1534, 1812, 1825 Alkylation unit............................................................160, 299 Aluminum tank................................................................... 1664 Ambulance............................................................................1701 Ampule..................................................................................1292 Autoclave............................. 133, 269. 414, 620, 701, 890, 974, 1219 Automatic fire protection system.................................... 1862 Ball mill......................................................... 307, 1109, 1722 Barge........................................................................................ 43 Battery.....................................................116, 284, 771, 1576 Blender..................................................................... 1746, 1924 Boiler.................................................................400, 922, 1703 Bomb1.2..6..7................................. 65, 258, 471. 475, 487, 1929 Boxcar......................................................................162, 1902 Canopy................................................................................. 1652 Capstan................................................................................. 1987 Carboy.................................................................193, 639, 764 Cast iron pipe......................................................................1623 Centrifuge................... Ill, 127, 229, 250, 336, 417, 542, 645, 748, 759, 781, 785, 876, 1131, 1173, 1197, 1215, 1254, 1458, 1478, 1688, 1780, 1796, 1837 -153- CMA. 048867 Chem-card............................................................................ 1170 Chlorinator................................................371, 445, 861. 901 Chute.....................................................................................1201 Cigarette lighter................................................................... 1175 Clothing.................................................... 613. 788, 840. 884 Coil...............................................................................81. 122 Column .......................................................................607, 924 Compressor............................35, 230. 231. 273. 356. 454, 518. 559, 576, 654. 694, 889. 1138. 1485, 1519, 1846 Condenser........................................95. 150, 209. 470, 1510 Contact lens........................................................... 1621. 2031 Control box............................................................. 342, 1586 Control room....................................................................... 1579 Converter................................................................................504 Conveyor..............................................398, 908. 1146, 1511. 2012, 2095, 2022 Cooling tower..................................... 385,488. 1179, 1250 Crane............................. 171, 380, 1618. 1735, 1922, 2092 Crucible................................................................................ 1263 Cutter.....................................................................................1202 Cylinder.....................................34, 39. 397, 406. 459, 500, 589, 683, 723, 744. 910, 937, 947, 953, 955, 1111, 1159, 1218, 1444, 1560, 1585, 1605, 1673, 1682, 1758, 1992 Cryostat...................................................................................776 Details................................................................................... 1110 Desiccator.............................................................................. 347 Detector, fire....................................................................... 1823 Diesel engine....................................................................... 1671 Disc, safety........................................................................... 659 Dome (tank)........................................................................ 2091 Drain......................................................739, 837, 1269, 2038 Drainage ditch .................................................................... 1709 Drier.......................... 1108, 1120, 1160, 1162, 1683, 1685 Drum......................... 16. 17, 31. 41, 72, 73. 91, 99, 107, 131. 140, 185, 186, 260, 262, 271, 292, 315, 322, 343, 351, 381, 425, 436, 483, 496, 498, 506, 515, 554, 610, 663, 682, 688, 690, 699. 700. 742, 769, 793, 832, 915, 958. 1153, 1171, 1180, 1273, 1274,1309, 1314, 1332, 1472. 1487, 1496, 1523,1524, 1527, 1533, 1548, 1596, 1626, 1648,1677, 1702, 1764, 1866, 1885, 1908, 1913,1936, 1952, 1955, 1965, 1966, 1970, 1998 Dry box................................................... 290, 717, 750, 1503 Dust collector.......... ................................................... 249, 372 Dyeing machine ..................................................................1927 Dynamite car ......................................................................... 570 Effluent tub......................................................... 283 Electrical..................................192, 272, 1239, 1319, 1578, 1590, 1728, 1791, 1819. 1874, 2079 Electrostatic precipitator..................................................... 344 Elevator...................................................................................388 Evaporator.............................................................................. 337 Exhaust blower............................................................ 703, 799 Exhaust vent.................................................................. 555, 643 Expansion joint......................................................... 444_ Explosion-proof light........................................................... Fan ........................................................................................ .. Feeder hopper...................................................................... 771 Filter........................................................524. 698. 898, I867 Fire alarm....... .................................................................. j 949 Fire box............................................................................... 1307 Fire extinguisher........................................................1714.177] Flaker........................................................................... 952, 1200 Flame arrester.......................................................................;72 Flame resistant clothing....................................................1642 Flare........................................................................................ 525 Float, metal...........................................................................970 Fluorescent light................................................................. 1787 Fractionator...........................................................................838 Furnace...............................215. 396, 489. 544, 593, 1151. 1450, 1535, 1961, 1990. 2067 Gantry................................................................................... 1788 Gas chromatograph.............................................................1717 Gas detector...........................................................................818 Gas heater........................................................................... 1230 Gasket...........................................................71, 429. 522, 563 Gauge....................... 330, 402, 466, 727, 901. 1732, 1844 Glass............................................................................1730. 1776 Glass pipe..................................................................... 404, 967 Glove.......................................................................................214 Glove box........................................................................... 1188 Gondola car...........................................................................319 Graining bowl.......................................................................350 Granulator.............................................................................. 959 Grinding wheel ....................................................... 1513, 1838 Gun....................................................................................... 1259 Flair, long............................................................................. 1748 Hand pump..............................................................................73 Heat exchanger.......................... 651, 807, 856. 1544, 1700 Hoist............................................... 390, 757. 789, 923. 1638 Hood...................................................................................... 1981 Hopper car....................... 33, 355, 606, 1134, 1514, 1816, 2066 Hose......................................... 82, 125, 157, 165, 187. 212, 286, 327, 334, 381, 386, 391, 422, 440. 629, 644, 649, 657, 682,685, 686, 708, 797. 817, 927, 930, 965, 968, 984, 1 100, 1194. 1246, 1276. 1317, 1448, 1495, 1606, 1668, 1724, 1756, 1757, 1793, 1798, 1808, 1835, 1875. 1879, 1882, 1901. 1920, 1969, 2070, 2075, 2078,2105. 2106, 2107 Hough payloader....................................................................27 Hydraulic jack.................................................................... 1967 Impact tester..........................................................................219 Impeller...................................................................................285 Incinerator................................................................... 341, 612 Industrial truck ............................. 225, 352, 483. 530. 614, 615, 621, 715, 716, 724, 738, 791, 841. 862, 942, 1116, 1333, 1663, 1676, 1711. 1783, 1821, 1830, 1921, 1925, 1926. 1971. 1973, 2015, 2024, 2027 -- 154-- CMA 048868 J^iction box ........................................................................1848 Kettle.......... ................ 119. 141, 169, 200, 248, 255, 257, 274, 562, 626, 659, 705, 706, 758, 850, 909 Kiln................................................................... 510, 533, 1163 Label...................................... 132, 243, 291. 574, 589, 711, 1308, 1675, 1678, 1693, 1778, 2028, 2064, 2069 Ladder................................... 1253, 1831, 1868, 1891, 2043 Lamp (explosion proof).................................................. 1766 Line............................. 16, 80, 82, 84, 102, 112, 120, 130, 146, 152, 188, 197, 205, 244, 246, 266, 276, 332, 334. 338, 349, 354, 358, 376, 399, 404, 448, 460, 465, 477, 478, 497, 509, 531, 540, 558, 580, 586, 587, 593, 619, 630, 641, 646, 650, 655, 675, 713, 740, 848, 865, 869, 892, 900, 904, 925, 956, 1012, 1024, 1028, 1046, 1091, 1103, 1122,1157, 1167, 1178, 1184, 1190, 1192, 1231,1233, 1244, 1252, 1295, 1441, 1453, 1481,1515, 1537, 1555, 1567, 1591, 1625, 1636,1707, 1723, 1734, 1749, 1765, 1799, 1801,1805, 1820, 1826, 1883, 1938, 1945, 1954, 1972, 2000, 2010, 2036, 2041, 2057 Line identification 1266 Plastic pipe...................... ............................ 877 Polyethylene..................... 203, 473, 749, 958 Polymerization kettle.... ............................. 119 Power line....................... ......................... 1662 Power tool........................ ........................... 1715 Precipitating tub............. ..............................52 Press.................................. ................ 110, 1339 Pressure dyeing machine .......................... 1637 Pressure vessel ............... ............................126 Pump .......................... 13. 58, 73, 92, 135, 164, 244, 265. 276, 294, 300, 366, 393, 410, 492, 600, 631, 718, 728, 763, 765, 769, 773, 806, 809, 824, 842, 865, 893, 902, 911. 951, 965, 979, 1150, 1268, 1275, 1298, 1305. 1324, 1330, 1440, 1551, 1562, 1616, 1674, 1789, 1807, 1814, 1877, 1888, 1947, 1975, 1996, 2005, 2047, 2052, 2055, 2086, 2090 Ramset gun......................................................................... 1547 Reactor..................................213, 353, 379, 392, 516, 517, 867, 928, 944, 1191, 1337, 1552, 1633, 1672, 1674, 1691, 2104 Refrigerator..................................................... 1644, 1794 Ring, finger................................................... 1318, 1470 Roofer's mop...................................................................... 1720 Rotameter...............................76, 270, 387, 527, 543, 733, 931, 932, 1907 Rupture disc................................................... 1640, 1939 chine ......................729, 741, 767, 777, 798, 1304, 1466, 1529, 1531, 1556, 1561, 1588, 1619, 1687, 1692, 1752, 1772, 1790, 1827, 1923, 1991, 2002, 2006, 2011, 2045, 2060, 2076 Manhole...... ............................................126, 139, 241, 548 Manifold...... ..........................................................................720 Manlift ....... ....................................................................... 1491 Marine......... ....................................................................... 1229 Mastic pot.. ................................................................ 220 Mercury cell ....................................................................... 1300 Mixer.......... ....................... 278, 348, 494, 521, 745, 766, 802, 803, 881, 1123, 1839 Safety cable.......................................................................... 1107 Safety shower..............................................................605, 639 Scaffold................................................................................ 1518 Screw conveyor.......................................................................44 Sewer...................................... 13, 56, 121, 535, 1141, 2102 Shaft bearing..........................................................................874 Shoes, conductive....................................................... 778 Shoes, high.......................................................................... 1988 Sight glass....................................... 78, 113, 204, 233, 346, 430, 438, 751, 875, 885, 940, 960, 983, 1224, 1285, 1755, 1857, 1858 Silo..........................................................................................696 Nitrator column................................................................... 128 Nitrometer..............................................................................318 Sodium cell..............................................................1136, 1620 Sphere..................................................................................... 537 Sprinklers.....................................................1237, 1729, 1928 Oil burner........................................................................... 611 Oxygen meter.....................................................................2058 Oven..................................272, 553, 800, 913, 1320, 1670, 1768, 1769 Stabilizer................................................................................. 501 Steam generator.................................................................... 173 Steam trap............................................................................1265 Still................................... 45, 60, 233, 263, 311, 320, 363, 412, 431, 561, 936 Paint spray gun................................................................... 1899 Pallet........................................................................ 225, 1731 Pebble mill ............................................................. 1299, 1617 Pfaudler kettle............................237, 254, 335, 1632, 1898 ^hiiladelphiagear reducer...................................................... 199 eon................................................................................... 1941 "illiot t plant............................................................................. 1804 Pipe...............................358, 575, 658, 712, 736, 762, 786, 813, 877, 895, 897, 918, 967, 977, 1264, 1462, 1559, 1655, 1656, 1697, 1836, 1983, 2042 Stirrer........................................................... 804, 1245, 1460 Strainer................ 420 Stripper................ CMA. 048869 ............ 1'61 Sulfur gun.................................................. 934 Switch............................................ 192, 198, 492, 628, 1313 Tank........................32, 81, 145, 165, 208, 217, 232, 234, 242, 277, 285, 298, 446, 455, 490, 568, 572, 575, 601, 602, 617, 674, 726, 746, 792, 905, 907. 916, 930, 1140, 1204, 1220, 1257, 1288, 1329, 1446, 1486, 1532, 1627, 1649, 1665, 1881, 1958, 2029, 2059, 2094 -155- Tank car................................ 235, 239, 281, 288, 310, 314, 373, 384, 394. 433, 536, 564, 570, 573, 596, 597, 652, 828. 835, 863, 871, 878, 927, 933, 978, 1152, 1172. 1255, 1280, 1331, 1338, 1471.1521,1540. 1563, 1601, 1629. 1630, 1705,1706. 1736, 1767, 1775, 1784, 1802, 1803,1835. 1861, 1876, 1937, 1980, 1994, 1995,2001. 2007, 2014, 2026, 2051, 2088 Tank truck...............................16. 306. 374, 512, 529, 566, 604. 660, 661. 752, 760, 770, 815, 826, 852, 879, 929, 939, 986, 1114, 1115, 1506, 1604, 1694, 1695, 1739, 1753, 1754, 1843, 1878, 1919, 2019, 2032, 2072, 2099 Tar stripper............................................................................ 409 Temperature controller............................................340, 1293 Test cell................................................................................1098 Thermocouple....................................................................... 100 Thermo-well......................................................................... 469 Titanium line....................................................................... 1290 Tools............................980, 1145, 1174, 1283, 1442, 1956 Torch............................................................................413, 514 Tower............................................................................331, 609 Truck, pickup......................................................................1864 Trailer................................................................................... 1963 Turbine ...............................................................339, 439, 812 Vacuum collection system.............................................. [(,34 Valve..................................16, 60, 67. 71, 83, 88, 90, 101, 106. 119, 133, 135. 148. 159. 168, 188 196, 226, 228. 236, 266. 279, 303, 317' 345, 357. 368, 370. 382, 405, 424, 45(y 486, 491,499, 523, 538. 545, 624, 669' 670, 687, 710, 779, 851, 864, 872, 883! 896, 945, 946. 962, 1112, 1135, 1169, 1223, 1232,1247, 1294, 1316, 1461. 1546, 1570, 1668,1679, 1699, 1704, 1725. 1773^ 1809, 1847,1851, 1852, 1873, 1889, 19O4' 1912, 1932,1962, 1997, 2023, 2046, 2049. 2056, 2063, 2077 Vaporizer .....................................................................608, 821 Vat.......................................................................................... 305 Vent................................................................... 555, 598, 1476 Vent stack.................................................................. 703, 2103 Waste basket...... Weir box............. Winch................... Winding machine Work permit....... ......1860 ........ 484 175, 485 ........ 426 ......1502 EXPLOSIONS & PRESSURE RELEASES Acetaldehyde............................................................... 117, 660 Acetic acid............................................................................1011 Acetic anhydride................................................................. 2029 Acetic mix .................... 277 Acetone ..................................................................1153, 1661 Agitation...............................................................................1881 Americium............................................................................1105 Ammonia......................................................... 792, 916, 1691 Ammonium nitrate........................................873, 1325, 1483 Ammonium perchlorate.......................................................881 Analyzer................................................................................. 280 Autoclave................................................................................620 Automatic fire protection system.................................... 1862 Ball mill......................... Batch............................... Battery............................ Blender....... ................... Blow-off line.................. Bomb............................. Boron/potassium nitrate Boron trifluoride........... Bromide.......................... Bromine.......................... Burner............................. Butadiene....................... Butyl peroxide............... .............................1109 .............................1771 116, 284, 771, 1576 .............................1924 .............................. 133 .................... 258, 475 ..................745, 1334 .............................1279 .............................1834 ............................. 675 .............................. 954 .............................. 790 ...................... 17, 302 Carbon disulfide H81 Carbon monoxide....................................................................34 Caro's acid............................................................................ 662 Catalyst................................................................................ 609,1484 Catch box............................................................................. 1321 Caustic................................... 186, 1055, 1243, 1527, 1574, 1741, 2088 Cellulose nitrate....................................................................514 Centrifuge.....................................................1072, 1688, 1837 Chlorine.............................................................................. 1035,2018 Chlorobutadiene....................................................................200 Chloroform/acetone........................................................... 1661 Chloroform/methanol......................................................... 498,1913 Chloroform/sodium methylate........................................... 693 Chloronitrotoluene............................................................... 907 Chromatography.................................................................... 592 Chromium trioxide/pyridine............................................. 1284 Chromous chloride............................................................. 1660 Cigarette lighter................................................................... 1175 Compressor................................................ 35, 273, 559, 576 Condensate receiver............................................................ 335 Container disposal............................................................... 210 Cresol.....................................................................................1649 Cryogenic purifier...............................................................1156 Cumene hydroperodixe.......................................................906 Cyanide................................................................................ 1270 Cyanuric chloride................................................................ 1869 Cylinder................................................................................ 1159 2,4-D 713 -156- 048870 ^^ective wiring ... ^Htnating mixture Dmorane................. Dicarboxylation .... Dichloroacetylene . Dimethylsulfoxide. Distillation............. Dowtherm furnace . Drain....................... Drier....................... Drum ...................... Dust....................... .................................... 446 .................................... 216 ..................................... 730 ...................................1191 ...................................1989 ...................................1187 ...............590, 616, 2008 ..................................... 544 .................................. 2038 ...................... 1068. 1120 1019, 1287. 1309, 1596 ................. 44, 249, 1815 Electric oven................... Ether................................ Ethyl alcohol/caustic.... Ethyl alcohol/hexane.... Ethyl acetate................... Ethylene.......................... Ethylene gylcol............. Ethylene oxide............... Ethylene polymerization Explosive ....................... .................................272 ......................516, 616 .............................. 1741 .............................. 1780 ................................ 986 ......................580, 712 .............................. 1789 .479, 560, 758, 792, 1666 ....................................... 424 ......................................1516 Fire box................................................................................ 1307 Fluorination.......................................................................... 1045 Fluorochloro lubricant.......................................... 1312, 1449 orosulfate ......................................................................1189 ctionator........................................................................... 838 Fumaric acid..........................................................................202 Furnace.......................................................... 396, 1450, 1961 Gas chromatograph............................................................. 1717 Gauge..................................................................................... 330 Glycol. ......... 464 Glvconitrile.......................................................................... 1240 Heater ............................ Heat exchanger............ Hexane.......................... Hopper.......................... Hot water..................... Hydrazine nitroformate Hydrogen ...................... Hydrogen (liquid) ....... Hydrogen fluoride....... Hydrogen peroxide...... ...........................................2025 ........................................... 1700 ........................................... 1898 ........................................... 1250 ............................................. 159 ..................................... 1010 347, 609, 1097, 1098, 1916 .............................. 1001, 1238 ........................................... 1605 ....................... 127, 431, 1121 Incinerator............................................................................1696 Isobutyl peroxide.................................................................. 579 Isopropyl chloroformate....................................................... 145 Isopropyl ether.................................................................... 1607 tox lines, ttle........ .........2089 ............274 Laundry.................................................................................. 309 Lead azide............................................949, 987, 1505, 2053 Maleic anhydride....................................................... 622, 2032 Mastic......................................................................................220 Mercury...................................................................................481 Methyl alcohol ..........................................................454, 1443 Methy laminobenzaldehyde................................................2101 Methylation............................. 1786 Methyl acetylene............................. 632 Methyl bromide....................................................................746 Methyl ethyl ketone............................................................1458 Methly parathion.................................................................. 371 Methyl vinyl ketone..........................................................1528 Methylamine ............................................................... 60, 1673 Mold...................................................................................... 1455 Molten metal....................................................................... 1800 Morpholine sulphenyl chloride.........................................1806 Naththalene/sodium.............................................................. 565 Natural gas.......................................................................... 1061 Nickel/caustic.........................................................................172 Nitrate, fertilizer..................................................................1326 Nitration............................................................103, 578, 1311 Nitric acid carboy................................................................. 193 Nitric acid drum.................................................................... 131 Nitric acid-ethanol...............................................................1582 Nitric acid tank car............................................................. 1152 Nitrile...................................................................................... 151 Nitroaniline.......................................................................... 1624 Nitroaniline chloride.......................................................... 1763 Nitrobenzene...................................................678, 944, 1482 Nitrobenzoyl chloride.........................................................1915 Nitrocellulose.....................................................304, 483. 638 N itrochlorobenzene............................................................. 1624 Nitrogen, compressor.........................................................1056 Nitrogen, cylinder.............................................................. 1059 Nitrogen peroxide/cyclohexane.......................................... 128 Nitroglycerin...............................................................734, 1102 Non-polar solvents............................................................. 1817 Oil burner.............................................................................. 611 Organic phosphate...............................................................1557 Oven...........................................................................1320, 1670 Oxidation pressure test........................................................ 395 Oxygen......................................................................... 720, 953 Oxygen, liquid............................................................824, 988 Pebble mill .......................................................................... 1299 1-Pentol.................................................................................. 363 Peracetic acid........................................................... 1795, 1804 Perchlorate..................................................................599. 1124 Perchlorate/polysulfide........................................................ 766 Perchloric acid.......................................................................799 Peroxide......................................... 412, 562, 719, 852. 1043 Pfaudler kettle.................................................................. 1632 Phenacetin.............................................................................. 759 Phenol...........................................................................790, 1646 Phenol formaldehyde ......................................... 1633 Phosphine............................................................................. 1066 Pilot plant...................................................... 664, 1804, 1907 Piping..............................................................................80. 1697 -157- cma. 048871 Plutonium............................................................................. 1053 Polyvinyl chloride................................................................960 Potassium, metal ................................................................ 1154 Pressure dyeing machine...................................................1637 Pressure vessel ......................................................................126 Process change ...................................................................... 526 Propane .................................................................................879 Propylene oxide............................................................ 31, 758 Pyrotechnic Hare...................................................................948 Reactor....................................................................... 353, 1337 Refrigeration generator..........................................................57 Resin.......................................................................... 963, 1633 Rotometer............................................................................. 1907 Salt bath.................... Sewer......................... Shock sensitive....... Sight glass................ Silicomanganese...... Silver, fulminate of. Silvering solution.... Soda ash.................... Sodium...................... Sodium amide......... Sodium bottle.......... Sodium bromide...... Sodium chlorite....... Sodium, metallic .... Sodium methylate... ..................1026 121, 535, 2102 .....................721 .....................454 .................. 1535 .....................976 .................. 1733 .................. 1964 .................. 1653 ................... 762 ....................132 ................... 874 ................... 839 ................... 781 ................... 693 Steam...............................................................846, 1967, 2010 Still............................................................................. 1088 Styrene.................................................................................. .. Sulfonation................................................................................. 944 Sulfuric acid.......................... 25, 76, 888, 977, 1496, 1533 Switch box...........................................................................mr Tank car....................... Tank entry.................... Tank mix....................... Tank truck venting...... Tetrafluoroethy lene___ Tetrahydrofuran............ Thiocyanate/nitric acid Trichlorethanol-caustic Trichloroethylene....... Uranium................................. 1767 634 1958 ..660 1520 ...77 ..853 1574 ..575 Vaporizer............................... Vinyl acetate......................... ..384, 2087 Vinyl chloride...................... ....................... 816, 1551, 2033 Vinyl cyanide........................ Vinlyidene............................. .......... 1172 Waste dmm.......................... .............315 Welding............................................................ 105 , 474, 1336 Xylene................................... ..748, 1593 FIRES Acetaldehyde............................ ..911 Acetic acid.................................. .1985 Acetic anyhdridc........................ .2029 Acetone...................................... .1153 Acetylene................................... ..744, 1992 Air compressor.......................... ,...35, 1534 Air mixing chamber.................. .1093 Aluminum isoperoxide............ .1171 Aluminum paint....................... ..104 Aluminum/steel......................... ..772 Ammonium perchlorate.......... ................... 845, 1002, 1768 Autoclave.................................... ..414 Benzene....................................... ........... 129, 703 , 823, 1141 Boiler............................................ ..400 Butadiene.................................... ..303 Butane sphere............................. ..537 Calcium cyanide ....................... Calcium hypochlorite............... Tarbon disulfide......................... Cartridges................................... Catalyst........................................ Chlorination................................ ..521 ...428 . 453 1872 1094, 1484 Clothing................................................................................. 884 Coal dust.................................................................................. 33 Cooling tower ..........................................................385, 1179 Cryostat.................................................................................. 776 Cyanuric chloride................................................................1869 Cylinder................................................................................. 397 Decarborane........................................................................... 749 Diesel engine....................................................................... 1671 Distillation............................................................................1900 Drum storage........................................................................ 997 Drier.....................................................290, 1030, 1462, 1683 Dry box................................................................................ 1503 Dust................................................................ 618, 1634, 1746 Electrical ................................................................... 348, 1328 Electrostatic precipitator..................................................... 344 Ether..............................................................................561, 676 Ethyl acetate.........................................................................2037 Ethyl chloride.........................................................................138 Ethylene................................................................................2047 Ethylene oxide.......................................................................479 Exhaust duct......................... 643 - 158-- CMA 048872 Flammable liquids ^Brnaldehyde..... ^Weezer.................. Furnace.................. Hammer.................. Hexane................... Hoist................... Hydrazine............... Hydrogen............... Hydrogen peroxide Hydrogenation,. .. .......... 1760 .......... 1319 .......... 1794 1151, 1990 .......................... 61 .......... 1898, 2039 ......................... 757 ....................... 1893 1098. 1257, 1297 .......... 1626. 1648 ......................... 490 Igniter mix............. Incendiary mixture Industrial truck .... Inert gas.................. ....................... 1183 ......................... 833 ......................... 614 ....................... 1970 Junction box 1848 Kiln .533 Laboratory............................417, 635, 859, 870, 880, 996, 1282. 1303, 1334, 1335, 1445 Lithium aluminum hydride.....................................676, 1494 Los Angeles, Aug. 1972..................................................1887 ^Methyl alcohol .................................... 219, 703, 964, 1254, 1506, 1796, 1933 Methyl chloroform............................................................. 1158 Mixer.............................. 803 Monoethanolamine............................................................. 1523 Natural gas............................................... Nitric acid ............................................................................1797 Nitrocellulose........................................................................ 483 Oil vapors......... Oxidizer............. Oxygen............... Oxygen cylinder ..................198 ................ 1583 ....1185, 1931 39, 500, 1560 Pebble mill ......................................................................... 1617 1-Pentol................................................................................ 363 Phosphorus.................... Polyethylene liner.......... Polymerization................ Polymerization oven...... Potassium permanganate Potassium persulfate...... Press................................ Propane ............................ Propylene oxide............. . ............................ 840 203, 473, 700, 958 ............................ 424 ............................ 553 .......................... 1842 ........................... 1155 .......................... 1339 ............................ 995 ..............................31 Resin 240, 255 Sewer........................ Soda ash.................... Sodium chlorate...... Sodium hydride...... Sodium isopropylate Steam lines............... Still............................ Styrene..................... Sulfonate................... Sulfuric acid............ Sunlight ................... ..535 1964 ..282 1587 1017 ..810 1016 ...41 . .653 1983 1005 Tank...................................... Tetrahydrofuran................... Titanium chlorides............. Toluene................................. Trichloroethylene/caustic .. Trioxane................................ Turbine oil.......................... ................ 617, 1881 .......................... 1299 ............................ 477 141, 688, 699, 742 ................ 495, 1065 ..........................1129 ............................ 339 Uranium foils 1296 499 Vinyl acetate......................................................................... 384 Vinyl chloride...........................................................625, 1113 Waste basket .. Waste solvent. Welding.......... Wurtz reaction .............................i860 ..............................341 359, 528, 633, 1490 ..............................456 Xylene............................................................................91, 1966 Acetic mix Acetone ... Autoclave. Benzene.............. ^Carbon disulfide . ^^R^atalyst............... Centrifuge............ Chlorothiazide ... Clothing ............. STATIC ELECTRICITY .................277 ............. 1933 ................ 414 ......129, 703 ......515, 558 ............. 1094 ............. 1072 .................700 ................ 613 Decarborane............ Detonating mixture Dioxane.................... Drum ...................... Ethyl acetate.......... Ethyl alcohol......... Ethylene oxide........ Explosive................ Flammable liquids. -- 159- ............. 749 ............. 216 ............. 610 1180, 1309 ............. 986 ....... .1479 ............. 479 .......... 1516 .......... 1760 CMA 048873 Hand pump.............................................................................. 73 Hydrogen sulfide...................................................................335 Ligroin.................................................................................... 876 Methyl alcohol...................... 703, 1443, 1822, 1933, 2085 Methyl ethyl ketone............................................................1478 Non-polar solvents............................................................. 1817 Phosphorus............................................................................ 468 Polyethylene liner.......................... 203, 473, 627, 959, 969 Production mix.................................................................... 13jq ?umP.............................. 1616 Sodium hydride.....................................................................9^9 Styrene..................................................................41, 674, 832 Toluene...........................................688, 699, 742, 886, 1685 Vinyl acetate......................................................................... 384 Vinyl chloride......................................................................1132 Xylene...........................................................................91, 1966 WASTE DISPOSAL Acid pump.............................................................................265 Naphthalene/sodium mixture..............................................565 Carbon disulfide.................................................................... 121 Caustic.................................................................................... 574 Chromic acid waste............................................... 1919, 2009 Drain....................................................................................... 837 Drum.....................................................................17, 131, 315 Ethyl chloride.........................................................................138 Phosphorus oxychloride.......................................................520 Potassium............................................................................. 1891 Sewer...........................................................................535, 2102 Sodium..............................................................68, 1566, 2082 Sodium azide....................................................................... 1957 Solvent.................................................................................... 341 Sulfuric acid..........................................................................978 Hydrogen sulfide............................................................ 54, 56 Triethylamine........................................................................ 793 Laundry.................................................................................. 309 Vinyl cyanide........................................................................ 262 Metal container..................................................................... 210 CORROSION Acid pump................................... ........................................265 Aluminum/pump......................... ...................................... 1888 Carbon disulfide.......................... ...................................... 1861 Centrifuge..................................... ........................................542 Chlorine....................................... ............................608, 1266 Cock............................................................................. 358, 478 Electric oven................................ ........................................272 Fan................................................ ........................................857 Fire extinguisher.......................... .....................................1714 Heat exchanger............................ ........................................856 Hose............................................... ......................82, 286, 310 Hydrogen peroxide...................... .....................................1626 Junction box.........................................................................1848 Line.............................................................................. 25, 399 Maleic acid.............................................................................817 Phosphoric acid.......................................................... 601, 962 Platform................................................................................. 461 Sulfuric acid...................................... 975, 1625, 1668, 1945 Thermo-well..........................................................................469 Valve....................................................................670, 872, 962 Vat........................................................................................... 305 Zinc drum.............................................................................. 261 PROTECTIVE EQUIPMENT Acetic acid........................................... 328, 805, 1609, 1985 Acetic anhydride.................................................................1905 Acid line...............................................90, 96, 106, 112, 358 Acrylonitrile Air line....... Air sparger.. -- 160-- CMA. 048874 1897 ..360 ..224 Aluminum triethy!................................................................819 ^mmonia.....................................................87, 230, 509, 709 Metal melting........................................................................ 732 Methyl vinyl ketone.............................................................260 Amyl acetate..........................................................................293 Aniline............................................................................ 32, 755 Molten metal....................................................................... 1698 Monochloracetic acid............................................. 1024 Mucochloric acid................................................................ 1186 Benzene............................................................................ 43, 81 Bomb.......................................................................................475 Nitrogen................................................................................ 1775 Bromine..................................................... 675, 786, 945 Nitrogen oxides ........................................................ 287, 1903 Butyl ether............................................................................1020 Nitrometer.............................................................................. 318 Car unloading........................................................................ 497 Carbon monoxide................................................................. 357 Carboy, acid..........................................................................764 Caustic.....................................85, 146, 149, 169, 185,480, 631, 1643, 1725, 1774 Centrifuge............................................................................. 1173 Chlorine................................ 86, 692, 808, 861, 919, 1041, 1144, 1272 Chloroform.......................................................................... 1686 Chlorosulfonic acid.............................................................. 642 Cleaning............................................................. 95, 342, 1130 Contaminated shoe............................................................... 452 Cyclohexylamine.................................................................. 682 Drain line................................................................................265 Drum...................................................................292, 425, 506 Ethyl alcohol....................................................................... 1780 Filter elements.................................................................... 1867 Fire box................................................................................ 1307 Flame resistant clothing.................................................... 1641 Formaldehyde.............................................................213, 381 Glycol..................................................................................... 464 Glycolnitrile.........................................................................1196 Fiard hat.................................................................................472 Harness..................................................................................... 52 Heating equipment................................................................ 100 Hexane................................................................................. 1780 Hoist....................................................................................... 829 Hydrochloric acid.............................................................. 1775 Hydrofluoric acid................................................................ 1278 Hydrogenation....................................................................... 305 Hydrogen cyanide.....................................................246, 1710 Hydrogen sulfide.............................................. 13, 538, 1 199 Incendiary mixture................................................................833 Instrument reading............................................................... 437 Kiln.......................................................................................... 510 Laboratory............................206, 227, 599, 677, 681, 750, 756, 1022, 1206, 1779 Lead azide.............................................................................. 987 Lead burning.......................................................................... 197 Line ............................................. 334, 460, 478, 1537, 1631 Phenobarbitol........................................................................ 389 Phenol.......................................................................................45 Phenyl hydrazine................................................................... 137 Phosphoric acid..........................................................851, 1046 Phosphorus......................................................... 215, 468, 840 Phosphorus oxychloride.......................................................433 Phthalic anhydride................................................................718 Polyethylene bottles.............................................................256 Polymer................................................................................ 1202 Powder....................................................................................757 Pressure testing................................................................... 1761 Propane..................................................................................1944 Pump .........................................................................1298, 1674 Reactor................................................................................. 1674 Rosin............................................................................. 173, 1338 Sampling............................264, 333, 540, 642, 1256, 1707 Sight glass........................................................113, 751, 1224 Silver, fulminate of..............................................................976 Sodium chlorate.................................................................... 282 Sodium cyanide....................................................................648 Sodium transfer.......................................................................99 Sprinkler.............................................................................. 1237 Showers................................................................................ 1669 Still..........................................................................................233 Sulfur dichloride.................................................................. 690 Sulfur dioxide........................................................................ 926 Sulfur, molten......................................................................1895 Sulfuric acid..................................83, 135, 967, 1668, 1983 Tank........................................................................................ 234 Tank car................................................................................. 288 Tank draining.........................................................................165 Tank entry................................................ 207, 416, 432, 442 Trank truck.............................................................................929 Tar.........................................................................................1725 Titanium chlorides............................................................... 477 Toluene diisocyanate.......................................................... 1332 Trichloro phenol................................................................. 1190 Ultra-violet............................................................................. 179 Valve maintenance.....................................................370, 545 Vinyl chloride......................................................................1818 Vinyl cyanide........................................................................ 364 Vinylyidine chloride............................................................. 110 -- 161 -- CMA 048875 Water............................. Welding....................... Xylene....................... Zinc chloride................. -- 162-- CMA 048676 HD 7262 .MI r.U C*1 687 Manufacturing Chemists1 Association, Inc, Case histories of accidents in the chemical industry DATE ISSUED TO GAYLORD*0 HD 7262 .HI .ii c.l 667 CMA. 048878 LIBRARY MANUFACTURING CHEMISTS' ASSN. INC. 1825 CONNECTICUT AVE,, N. W. WASHINGTON. D. C. 20009