Document e5YQKaDze2dmw3Vmy220q96Zg

R&S 038801 15 April 1986 V/ ft ! Members of the Manufacturing Practices Committee (or whatever It Is called now): Mv attempt to put something together from the old CMA booklet and your consents Is attached, and Its your turn now. Please let me have your comments by 20 May so we can give the Board a prorgress report at Its meeting. Don't be afraid to participate. If your pet concern Is left out, or you find an error - mark It down. DTB:pbr 0781c RECEIVED APR 29 1986 CEP &T0X TECH CTR. R&S 038802 DRAFT RECOMMENDATIONS FOR THE STORAGE, SHIPPING, AND HANDLING OF VINYL CHLORIDE These recommendations have been prepared by the Vinyl Institute as a service to its members and their customers and is based on information believed to be accurate. No warranty or guarantee is made for accuracy or completeness, however, and all responsibility for safe handling and compliance with regulations lies solely with the user. Introduction Vinyl chloride and its polymers have been in commercial use for more than half a century. The Safety Subcommittee of the Manufacturing Practices Committee of the Vinyl Institute has prepared these recommendations from the experience gained during that period so that those handling vinyl chloride might share the benefits of that experience. The excellent safety record of the industry has been the result of strong and diligent efforts by the participants, and it should be useful to share the lessons which have been learned with others. Some useful background information is presented first, then a discussion of factors to be considered in the design and operation of storage and handling faci1ities follows. -1- Physical and Chemical Properties Relevant physical data are presented in Table I. It is important to understand that while generally quite stable chemically, the formation of unstable peroxides occurs readily in the presence of more than a few parts per million (ppm) of oxygen, particularly when water, acid, iron salts, or certain organic impurities such as acetaldehyde are present. These peroxides can detonate upon heating or under friction, and can initiate polymerization under some conditions. R&S 038803 Table I Selected Properties of Vinyl Chloride Boi1ing Point Freezing Point Flash Point, Open Cup Autoignition Temperature Critical Temperature Critical Pressure, psia Explosive Limits in Air, 1 atm.p 25C, Volume Percent Liquid Density at, F, g/ml Vapor Pressure at, F, psig Vapor Cloud Explosion Yield (lb. to yield the equivalent of 1 ton of TNT) F C 7.0 -245 -108 882 317 -13.8 -154 -78 472 158 775 3.6 to 33 0 25 50 75 100 125 0.975 0.95 0.93 0.91 0.88 0.85 0 -4 25 11 50 30 75 39 100 60 125 78 150 96 24,305 -2- R&S 038804 Toxicological Properties The most significant acute toxicological property of vinyl chloride is its anesthetic capacity. This effect becomes important at about 8,000 ppm, and can cause death after a short time at the low percent level. Cardiac arythmia has been seen in dogs anesthetized with vinyl chloride. Reversible liver enlargement was reported at exposures as low as 50 ppm in rodents for a few weeks. Liver cancer (angiosarcoma, ASL) has been seen in mice after a lifetime exposure at that same concentration, and in other mammals at higher levels. Workers exposed to concentrations thought to be approaching a few thousand ppm for several years also have developed ASL. Some 32 deaths in the U.S. and about 1 1ST in the free world have been reported from this cause. Vinyl chloride has a relatively high heat of vaporization, and thus large spills will liquify partially. This presents a hazard of frostbite to workers, as well as increasing the fire danger. The odor of vinyl chloride is too mild to be useful as a warning of its presence. Most persons cannot detect less than 1,000 ppm. Regulatory Status Only a brief summary of the regulations pertaining to VC will be given here. Each manufacturer or user must become familiar with the details of the rules and develop a site-specific plan for compliance. -3- OSHA Vinyl chloride is regulated as a carcinogen at 29CFR1910.1017. Extensive work practices, training, labeling, and recordkeeping requirements are detailed there. Some of these are discussed in later sections. EPA Emission standards for VC manufacturing and polymerization facilities are found at 40CFR61.64. Here, too, work practices are specified, and preventable relief valve emissions are prohibited. Many states have assumed the enforcement authority for this rule. A recommended maximum concentration limit (RMCL) in drinking water has been set at zero (40CFR141.50), and an enforceable maximum concentration limit (MCI) of 1 ppb has been proposed. Vinyl chloride, ethylene dichloride, and several of the wastes from their manufacture are listed as hazardous wastes under RCRA at 40CFR261. The interim statutory Reportable Quantity (RQ) for reporting a spill under CERCLA is 1 lb. The final RQ value has not been set. The statute exempts "federally permitted" releases .from the reporting requirements, but the EPA has not yet defined that term. R&S 038805 FDA Polymers and copolymers of vinyl chloride currently are Generally Regarded as Safe (GRAS) for many food-contact applications and are formally approved at a number of places in 21CFR172, 175, 177, 179, and 181. The FDA has proposed to establish limits of 5-50 ppb for residual vinyl chloride in the polymer used for such purposes. DOT Vinyl chloride is listed as a hazardous material. Railcars for bulk shipping must conform to the specifications of types 105 or 112, including head shields, spade couplers, and sheathed insulation. Full and empty cars must be placarded as discussed below. Storage Vinyl chloride storage areas should be selected and designed to comply with all applicable local codes and regulations. Organizations such as The National Fire Protection Association, The National Board of Fire Underwriters, and the Factory Insurance Association can be consulted about proper site selection. Adequate separation between tanks and from other structures is the primary concern. -5- R&S 038806 Conditions of Storage Vinyl chloride may be stored for reasonable periods of time without danger from hazardous decomposition or polymerization when kept in contact with ferrous materials and in the absence of air, oxygen, water, light, or excessive heat. Nitrogen blanketing may be required under some conditions to increase the storage pressure in order to facilitate tank pumping operations. Refrigeration can be used in hot climates to maintain the storage temperature within a desirable range--below 5QF and preferably between 0C and 20,,C. In a few instances vinyl chloride is stored as a cryogenic liquid. Steel is the preferred material of construction for handling vinyl chloride. Stainless steel should be used for conditions where water may be present, such as in recovery and recycle operations. It has been found that 316L is preferred in this service to prevent chloride-indudaistress corrosion at weld lines, particularly if the service is above 40C and polymer deposition may occur. Cast iron is not suitable for piping, pumps, or valves because of its very brittle nature. Aluminum is not recommended for use with any chlorinated materials. Copper and its alloys are acceptable for instrumentation parts, but stainless steel tubing is preferred for major tubing runs because of its superior mechanical properties. -6- R&S 038807 R&S 038808 All-welded construction is recommended whenever possible, except for connections to vessels. If flanged construction is needed, as in lines subject to polymer build-up, adequate electrical bonding and grounding is necessary. The resistance to ground should not exceed 25 ohms. Threaded fittings (except for instrument connections) are not recommended, and if used, should not be less than 1-1/2 in. in size. There should be no threaded connections on storage tanks. Top-entering inlet and outlet connections are preferable. When that is not feasible, there should be remote actuated shut-off fire-safe valves at the tank connection. A section of plastic instrument air tubing and an air-to-open valve adds to the ability to assure rapid closure in case of a fire. All other tank connections should have a manual valve mounted directly on the tank flange. The valve under the relief assembly must not close off all relief devices at one time. The ability to flood a tank with water from the bottom also gives added protection against mechanical failures in bottom-connected lines. Storage tanks should be painted with light-reflective coatings to reduce heat absorption. Support legs and at least the lower part of the tank should have heat-resistant coverings. The area should be diked to contain any liquid spillage, but sloped so that the pool is not held beneath the tank. Consideration should be given to a remote method of ignition of a pool should it develop. -7- Storage tanks should have automatic sprinkler/deluge systems of a type approved by the applicable local and national codes and actuated by temperature rise and/or vapor detection. Turret nozzles are especially useful for localized cooling in case of a fire. Design of the diked area should contemplate the volume of water or other firefighting liquid or foam which may be added Liquid vinyl chloride would tend to float on any water or ice, and the rapid vaporization from contact with the warmer water will increase the rate of vaporization of the vinyl chloride, which then will freeze large quantities of water with considerable trapped vinyl chloride vapor. 30 So CO eB8e0 Adequate separation should be allowed between storage units for effective maintenance or fire fighting, and to prevent excessive heat transfer in case v-. fire. Maximum feasible separation should be provided from sources of ignition such as furnaces, maintenance areas, or non-enclosed electrical stations. The design working pressure should be at least 150 psig. Hydraulic relief valves should be provided on all pump casings and piping sections which could be isolated by valving off from the main storage vessel. Adequate pressure relief valves for fire conditions should be placed on the main vessel. Dual systems with a 3-way valve on the tank which cannot close off both systems at the same time are useful for maintenance. The EPA standard requires that a rupture disk be present before all pressure relief valves which are not vented into a recovery or abatement system. Such venting can be used for hydraulic relief valves which will be called on to vent only small volumes, but should -8- never be used on primary storage vessel relief systems. There the relief valve tail pipe should be as short as possible, with no more than one elbow. All storage tanks must be labeled as required by the OSHA standard, as well as meeting any local rules. All wiring in the storage area must meet applicable national or local codes, and should conform to Class I, Group D, Division 1, as a minimum. Panel-mounted sight glasses with 1ight-absorbant glass are preferred to the stand-off tubular type gauges. If the latter are used, the check valves and glasses should be inspected regularly. A detailed preventative maintenance program should be developed which assures bench testing of all relief valves, pressure gauges, level indicators, and other such critical devices used in the handling of VC on a regular basis. A written record should be maintained for all inspections and tests which are performed. Bulk Transport All bulk transport vehicles should be inspected for mechanical integrity and to Insure the identity of their contents before they are placed at the loading/unloading station. The station equipment should be Inspected carefully before each use. Any defects should be reported at once, and no attempt should be made to unload until the defect is remedied. Loading and unloading -9- 188o operations are required to be under constant surveillance by the Department of Transportation (DOT). Bulk vessels should be dedicated to vinyl chloride service, and should be kept under 10 psig pressure at all times to prevent entry of air. If nitrogen padding is used to assist unloading in very cold weather, the supplier should be informed by that fact before the vessel is returned. No container should be filled to more than 85% liquid full. The design of the loading station should provide sure footing for the operator in all types of weather, and conform to OSHA standards for elevated work platforms. Proper counterbalancing and support of the hoses and connectors is needed to reduce operator effort and to assure tight connections. Only top unloading vessels should be used. Consideration should be given to the drainage of any massive spill away from the major operating area. The location of the station should provide maximum separation from these operating areas, and minimum pipe runs to storage. It should be as far away from major traffic areas as feasible. Many employers require the use of full protective gear while connecting and disconnecting loading lines, pumps, and during other operations where large concentrations of VC may occur. OSHA requires such protection where liquid may be encountered. A complete safety shower/eye fountain should be located within about 25 feet of all loading/unloading stations. CHEMTREC should be notified immediately at 1-800-424-9300 of any transportation or other emergency involving.vinyl chloride. -10- R&S 038811 Railcars. Accumulation or storage of railcars containing vinyl chloride. either full or empty, in areas accessible to the public should be avoided, if for no other reason than to avoid public concern. The Compressed Gas Association has developed an emergency dome repair kit for field use when leaks develop in that area. Pamphlet P-10 is available from the CGA in Washington, D.C. Shippers and users should become familiar with the nearest location of a kit. Many VC producers also have developed emergency capping kits and field valve change-out procedures. Each user of VC should discuss with its suppliers the procedures and facilities available for emergency situations before the problem arises. The SPI sponsors a mutual aid organization that will provide advice and field assistance if needed. It can be contacted through CHEMTREC or at ______________ The evaluation of disposal methods for vinyl chloride from cars involved in serious train accidents must be done on a case-by-case basis. Several recent events have been resolved safely by piercing the derailed car with a shaped charge, followed by ignition of the venting gas. Derail devices or a locked switch and warning signs must be in place whenever railcars are connected to the station. Brakes must be set and the wheels blocked whenever the car is connected. Bulk Trucks. It is particularly important to observe the grounding and chocking rules for trucks during their unloading. If the tractor unit is to be moved, it should be done before the unloading operation; and not returned until the connections are purged and open. -11- R&S 038812 Clearance of at least two feet on each side and four feet on each end of the trailer should be provided. The station should have a level, smooth pad that is curbed and drained away from the trailer and pump station. Barges. Coast Guard rules apply to barge shipments. The principles for safe handling are not different for barges than for rail or truck movements, of course. The larger quantity involved calls for a proportional degree of care being applied. Cylinders. No cylinder should be filled with vinyl chloride or any other substance without explicit permission from the owner. Cylinders for shipping vinyl chloride are regulated by the DOT under rules found at 49CFR173 and 304. The outlet valve(s) must have a suitable protective cap. Cylinders with brazed seams are not permitted; seamless cylinders are preferred. Maximum allowed tillage is 84%. The same general labeling requirements apply to cylinders as to other containers. Cylinders whose inspection expiration date has been passed must be tested and inspected before the next refilling. Only pressure reducers designed for VC and having the proper threads should be used. Any manifolds or piping systems should have proper pressure relief devices and an effective check valve so that other materials cannot be backpressured into the cylinders. Sample Containers. Sample containers that are to be shipped in interstate commerce must meet the conditions referred to in the preceding paragraphs. Cylinders for local use should be of no less quality, buty^ will be lighter ai smaller, generally. Double-valved cylinders are preferred in order to be suitable for the pass-through sampling system required by the EPA standard. -12- R&S 038813 R&S 038814 Samples not exceeding 300 lbs. may be shipped by cargo plane, but not in passenger planes, or as luggage. See 49CFR173.304, .314, and .315 for detai1s. Labels Labeling requirements of the DOT can be found at 49CFR172.101(e). Each container must have on it a label or placard identifying the contents as VC, a flammable gas, and using the identification number UN1086. "Empty" vessels must have a placard reading "Residue" and giving the UN1086 identifier. See 49CFR172.203, et. seq. OSHA requires (29CFR1910.1017) that all areas where exposure may exceed 0.5 ppm on an 8-hr. average be posted with "Cancer-Suspect Agent Area, Authorized Personnel Only" signs, and all stationary containers of VC labeled "Vinyl Chloride, Extremely Flammable Gas Under Pressure, Cancer Suspect Agent." Shipping containers must be labeled in accordance with 49CFR170-189, and "Cancer Suspect Agent" added near the placard. Containers of PVC, including shipping vessels, must be labeled similarly, unless specifically exempted from the OSHA rule. Emergency Response // The first action in case of an emergency outside a manufacturers or users facility should be to notify CHEMTREC and the local authorities, most often the State Police, in order to set in motion the extensive assistance mechanisms which are available. -13- R&S 038815 Inside a regulated facility there is required to be In place a detailed emergency response program. This should be initiated as quickly as an emergency is recognized. OSHA forbids entry into areas with concentrations over 36,000 ppm <3.61--the lower explosive limit) except for rescue, even with full protective gear. This prevents some response actions that may have been considered acceptable in the past such as plugging small holes or changing a valve "on the fly." Real emergencies seldom involve such small occurrences, and broader actions usually are required. While awaiting professional assistance, some actions can be begun: 1. Injuries. Injured persons should be removed as far from the site as the injuries allow. 2. Traffic control. Set up barriers to prevent entry by untrained persons on the site. cC 3. Evacuation. Consideration should be given to^evacuating at least a quarter- to half-mile radius around a railcar or bulk truck to avoid flying fragments in case of an explosion. Geographic or weather conditions may suggest other distances as more desirable. 4. Response headquarters. A safe but usable site for response headquarters should be selected and responders directed to it. -14- P<26*^'e 5. Fact collection. An effort should be made to -present as much information on the cause and results of the incident as is feasible. 6. Authority. As response develops, it is important that one person be given the overall authority. The official function of that person will vary from state to state, but conflicting activity must be avoided. Neither consignees nor shippers usually take a decision-making position, but can be valuable advisors. Persons responding should have, as a minimum, the following equipment: 1. Protective clothing and scuba gear. 2. Vapor detection devices usable in the ppm and percent ranges. 3. Appropriate outdoor clothing. 4. Ropes, traffic warning devices. 5. First aid gear. 6. Portable radio. 7. Portable lighting. 8. Capping or plugging equipment. 038876 jp Anyone responding should be prepared to stay several hours at the site, and should have replacement or backup personnel assigned. Every event must be evaluated on a case-by-case basis, thus relevant experience is of great value. Hazards presented by other containers or vehicles involved in the accident can be of great significance. Concealed damage may be a problem not recognized at once. Water may be useful to cool equipment, but is -15- not an effective fire control medium, and may only spread other substances involved. Fires should never be extinguished unless the source of the fuel has been controlled. Flashback from reignition at hot surfaces is a real danger at the fire scene, and it is very probable that if a vapor cloud is allowed to escape it will find a source of ignition, with the resultant major damage from such an explosion. If there is danger of a loaded car rupturing from external heat, or if it does not appear possible to right the car or transfer its contents to other vessels, serious consideration should be given to deliberate piercing of the shell and simultaneous ignition of the contents. This has been used successfully in several instances. 2009C-FI -16- -j 35 So CO