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AGENDA FOR INDUSTRIAL HYGIENE MEETING OF JUNE 22 1. Introductory Remarks - J. D. Harper 2. Effect of Fluorides on Humans - Dr. D. A. Irwin 3. Effect of Fluorides on Domestic Animals - Dr. L. V. Cralley 4. Effect of Fluorides on Vegetation - Dr. L. V. Cralley 5. Rockdale's Preventive Program - J. E. Yates 6. Scrubber Efficiency Tests - S. A. Jones 7. Vegetation Surveys - H. A. Semken 8. Aims and Purposes of a Plant Industrial Hygiene Program - Dr. L. V. Cralley 9. Other Smelting Plant Industrial Hygiene Items - R. R. Sugg 10. Tour of Smelting Works 11. Lunch 12. Tour of Mining and Power Production Facilities 13. Questions Regarding Tours 14. Industrial Hygiene Problems in Connection with Power Production S. A. Jones 15. Rockdale's Medical Program - Dr. J. T. Richards ; Rockdale's Safety Program - W. G. Martin 17. Discussion 18. Dinner at Taylor Country Club 411082 0415 ROCKDALE INDUSTRIAL HYGIENE MEETING OF JUNE 22 On June 22, an industrial hygiene meeting was held at Rock dale Works. The meeting was the first of the newly formed Rockdale Industrial Hygiene Committee and was heldprimarily to acquaint mem bers of the Texas State Department of Health with the industrial hygiene problems in connection with the aluminum smelting operations and the steps which had been taken or were planned at Rockdale to solve these problems. The meeting began at approximately 9:30 a. m. with the following present: State of Texas - Department of Health - Austin Henry A. Holle - Commissioner of Health Martin C. Wukasch - Sr. Engineer (Industrial Hygiene) G. R. Herzik, Jr. - Chief Engineer J. V. Irons - Director of Laboratories David F. Smallhorst - Engineer (Stream Pollution) Harris Bell - Legal Consultant State of Texas - Department of Health - Houston Otto Paganini - Engineer Milam County Health Unit - Cameron John B. Bryson - Director D. S. Wimberly - Sanitation Engineer Pittsburgh Office Dr. D. A. Irwin Dr. L. V. Cralley Point Comfort Works B. H. Sloane B. R. Hood 411082 0416 Houston D. T. Searls Rockdale Works J. D. Harper R. R. Sugg H. A. Semken J. E. Yates H. D. Franklin S. A. Jones W. G. Martin P. L. Hartsock J. H. Johnston W. H. Shepard J. T. Richards R. C. Wybourn (consulting radiologist) 411082 0417 Introductory Remarks - J. D. Harper Mr. Harper opened the meeting by welcoming the guests. He continued with remarks on the formation of Rockdale's Industrial Hygiene Committee and a discussion of aluminum plant operations. In discussing aluminumplant operations a flip chart was used to show plant layout, design of pots, and the process of producing aluminum. He called on Mr. Sloane to discuss smelting operations at Point Comfort Works. Mr. Sloane explained the main differences between the Rock dale and Point Comfort processes for producing aluminum and invited the State Health Department group to visit Point Comfort Works at some future date. Mr. Harper then described briefly how the increased fluoride emanations, associated with the large increase of aluminum production during World War II, resulted in a recognizable industrial hygiene problem. Effect of Fluorides on Humans - Dr. D. A. Irwin In the Hall process for smelting aluminum, aluminum oxide is dissolved in molten cryolite and decomposed electrolytically to metallic aluminum and oxygen. In the process, the molten cryolite also decomposes to a slight extent giving off gaseous hydrogen fluoride and some fluoride as fume. This fluoride release should be recognized as an inherent part of the operation that can be controlled by engineering methods so that working environments are safe, and plant effluents cause no damage to domestic animals or crops in the vicinity of a plant. 411082 0418 The Company's experience with excessive fluoride in drinking water is of historic interest. At the bauxite mining operations in Arkansas, deep wells had been drilled to supply water for plant anc domestic use. Years later it was observed that the permanent teeth of children who had drunk the water during their lifetime showed "mottling". Such "mottling" is now known to be due to excessive fluoride intake in early childhood. Analysis of the water showed the usual concentrations of minerals other thanfluoride, which was present to the extent of 14 ppm. Mr. H. V. Churchill, Chief of the Analytical Division of Aluminum Research Laboratories, announced these results in 1931 and pointed out for the first time the probability of a relation ship between fluoride intake and tooth "mottling". In 1937, Roholm published his book on the potential effects of excessive fluoride absorption by industrial workmen. This study reported on clinical findings in workmen exposed to dust concentrations of 22 to 48 mgs per cubic meter, having a cryolite content of 94-99% and a particle size of 50% below 5 microns. This is far beyond expo sures present in aluminum smelting operations. We made a study of the possible untoward effects of fluoride absorption. This study, which included clinical and industrial hygiene investigations, was made with respect to fluoride exposures of ten years ago, andprior to the introduction of remedial engineering. The exposure in smelting plants was found to consist of approximately equal parts of gas and dust. The studies evaluated the fluoride exposure in terms of 411082 0419 atmospheric concentrations and urinary elimination of fluoride in spot and 24-hour samples. X-ray films of the chest andpelvis on a routine basis gave information about bone density. No evidence of disability due to chronic fluorosis was found. Similar results were published by Agate following a clinical evaluation of British potroom workers. Ma rked imp rove ment in the ventilation of potrooms has taken place over the years, as can be seen from these figures showing fluoride concentrations in the potrooms before and after the improvement in ventilation was made. The Rockdale Plant embodies the advances that have come from the Company's experience of over fifty yea rs in smelt ing aluminum. Pot enclosures, fume removal systems, and excellent ventilation have made fluoride exposure noproblem. The working areas arepracticallyfreefromfluoride exposure, anditis known that urinary fluoride is within normal limits. The local fluoride situation, however, has influenced the medical program at Rockdale Works. Drinking water with high fluoride content is known to exist in districts close to Rockdale. A recent U.S.P.H. S. study, published by Dr. Leone and his group, compares a clinical evaluation of the residents of Cameron, where the fluoride content of the water is low, with those of Bartlett, where the water is high in fluoride. Some Bartlett residents were found to have in creased bony density of no clinical significance. Since the beginning of plant operations the preplacement physicals have included X-ray films of both chest and lower back. This procedure which was intro duced to record the bone density at the time of employment, could 411082 0420 obviate claims that plant exposure has caused increased bone density, actually due to the drinking of water rich in fluoride. Effect of Fluorides on Domestic Animals - Dr. L. V. Cralley The question of the effect of fluorides on domestic animal*; in the area around the Rockdale plant is parallel to that of typhoid fever in public health. With proper methods of public health engineering, typhoid fever ceases to be a public health problem. Likewise, the control measures installed at the Rockdale plant to prevent the atmos pheric pollution will effectively prevent fluorosis in domestic animals in the area. However, poor farming and animal husbandry practices may result in "off condition" among both animals and vegetation. In some instances, these conditions may be blamedonfluorosis by associ ation of the nearness to industrial operations. A proper diagnosis can be made by use of the following data: 1. Total intake of fluoride in the forage, mineral supplement, water, etc. 2. Urine fluoride excretion tests. 3. Analysis of bone for fluorides. 4. Examination of the animal by experienced veterinarians. Effect of Fluorides on Vegetation - Dr. L. V. Cralley The exposure of vegetation to gaseous fluoride below the threshold concentration of tolerance will cause no injury even though the fluoride content of the tissue rises considerably. The physical 411082 0421 appearance of vegetation injured by fluoride is not sufficiently char acteristic to be used diagnostically. Other causative agents, such as poor water balance, diseases, food deficiencies, climatic conditions, etc. , may give rise to appearances resembling those resulting from fumigation to industrial gases. Again, the diagnosis of fluoride injurv to vegetation requires the skill of experienced pathologists and physi ologists who are acquainted with both the fluoride resistant and the fluoride sensitive species of vegetation. Aclose study of these species, coupled with the meteorological data permit a conclusion to be reached. Chemical analyses may be useful as an adjunct to the above but are of little value by themselves in making a diagnosis. Rockdale's Preventive Program - J. E. Yates No fluoride problem was recognized prior to World War II. This was probably due to the comparatively small size of plants prior to that time, as well as the fact that climatic conditions and agricultural activities in locations of plants were such that the wrong set of circum stances did not exist; also, it is possible that border-line Droblems may have existed that were not recognized. A fluoride problem was first recognized at West Coast plants during World War II. A Company-wide corrective program was undertaken as soon as the problem was recognized. This program was participated in by all the smelting plants, the engineering staff of the Pittsburgh Office, and our research organization at New Kensington. The Company also 411082 0422 engaged the assistance of outside engineers and research concerns, as well as the manufacturers of specialized equipment. The program resulted in corrective results, tailored to the specific needs of each plant, being installed at the old plants. Corrective facilities were con sidered an integratedpart of the design of the Point Comfort, Wenatchee , and Rockdale plants which have been built since that time. Corrective facilities at Alcoa Plants are common in that the fluorides are collected at their source by hooding the electrolytic cells, draft is maintained on these cells by connections through duct work to exhaust fans, adequate exhaustbeing maintained on each cell to assure complete collection of fluorides, and the fluorides are removed from the air stream before it is exhausted to the atmosphere. Facilities at plants vary in detail as required by differences in plant design and lay out. Rockdale's system is the result of 8 to 10 years of development work. The Rockdale cells are hooded by means of portable aluminum covers, draft is maintained by exhausting 2000 to 2500 CFM per cell, the cells being connected through duct work to exhaust fans located between the potroom buildings. Particulate material consisting of alumina, carbon, and fluorides is collectedin multiclones and electro static precipitators. Gaseous fluorides are removed from the air stream by treatment in washing towers. Material collected by the multiclones andprecipitators is redistributed to the electrolytic cells. Fluorides collected in the washers are converted to calcium fluoride by the additon of lime to the wash water. This non-useable material in drawn out of the system as sludge for disposal. 411082 0423 Rockdale's Preventive Program-Scrubber Efficiency Tests-S. A. Jones Periodic tests are runonour fume collection system. These tests determine the operating efficiency of the system and also establish the fluoride loss from the system. The dust collectors, which consist of multiclones andprecipitators, are tested by using paper thimbles in the ducts following the collectors using standard dust collecting systems. In sampling, the ducts are traversed for an 8-hour period to establish particulate lose from the unit. The scrubbers are tested by using caustic charged impingero to determine the fluoride content of the gases going to the scrubbers, and a similar arrangement to determine the amount lost to the atmos phere. The scrubbers operate with a normal fluoride removal efficiency of 90 - 92%. Rockdale's Preventive Program - Vegetation Surveys - H. A. Semken As a further check on the efficiency of our fluoride collection system, a monthly surveyis made of the fluoride content of vegetation in the vicinity of the plant. These monthly surveys were begun 6 months before the start of operations in order to establish a normal for the fluoride content of the various types of vegetation in the plant area. The surveys have been continued on a monthly basis since that time. 411082 0424 On the slide now being shown are plotted the fifty-six locations at which vegetation is presently being sampled. The greatest number of sampling stations are to the north of the plant in the direction of the prevailing wind, with the next largest number to the south of the plant in the direction of the next most prevailing wind. Samples are taken a3 far as 6-1/2 miles from the plant. This slide lists a comparison of the fluoride content of the various types of vegetation before the start of operations with their contents in 1953 and 1954. Results thus far in 1955 indicate practicall/ no change from the same period in 1954. This slide shows the average fluoride content of vegetation, at increasing distances from the plant in 1 mile increments, for the years of 1953 and 1954. Dr. Holle asked if the results shown indicated a safe level of concentrations. He was told that the results were well within what was considered to be safe. Aims and Purposes of a Plant Industrial Program - Dr.L. V. Cralley The industrial hygiene problems of a new plant are naturally few in number since adequate controls have already been installed to handle hazardous materials. However, there are changes from time to time in both materials and equipment. The function of the industrial hygiene program is that of a watchdog to see that controls are main tained in good operating condition and new materials or equipment do not introduce new health hazards. 411082 0425 Other Smelting Plant Industrial Hygiene Items - R. R. Sugg In the operation of the Smelting Plant, there are many other items of industrial hygiene interest. Among these are dust, noise, and heat. Dust occurs from the handling of various materials. The materials handled in the greatest volume are alumina, coal and coke. These are relatively inert materials, and dust from them presents mainly a housekeeping problem. Fluoride bearing materials are handled in small volume and are of such a physical nature that dust is a minor problem. Dust is controlled by the use of collectors and precipitators as well as by using stockings and swing-spouts. Noise comes from ball mills, tumbling barrels and jolting machines. It is controlled by the proper location and design of the equipment as well as by the use of linings in some instances. Heat, which adds to the discomfort of the personnel, is found in several departments. It is combatted by instruction in health habits and personal hygiene; by the use of proper clothing; by the use of pro tective equipment; and by tool and equipment engineering. Among other items of industrial hygiene interest are our potable water system, sewage disposal plant and shower room facilities. Potable water is supplied from drilled wells and receives treatment which brings it well within State Health Department require ments. The system is under the direct supervision of a chief operator who holds a Texas class B license in well and surface water control. *11082 42q The sewage disposal plant is a package type, mechanical aeration, activated sludge system. The oxygenated sludge decomposes and the clear liquid is chlorinatedandpumped into the Power Plant Lake. Daily checks are made on the chlorine content of the effluent. Shower room facilities are well in excess of the minimum recommended by the American Standards Association. All restrooms are supplied with hot and cold water, powdered or liquid soap and paper towels. Lunch rooms are located at convenient places throughout the plant and are provided with water coolers, refrigerated bottle or lunch coolers, and hot plates. Plant Tours Shortly after 11 o'clock, the group left the conference room for a tourofthe Smelting Plant. The routefollowedcoveredourcarbon production, potlining, rodding, aluminum smelting, metal service, shower rooms, and machine shop. The visitors were very interested in all phases of the work and were particularly impressed with our fume collection systems. Along the tour, they frequently expressed surprise at the cleanliness of our plantand at the apparent good working condi tions. The comments of all members of the group were very compli mentary. After lunch, a tour was made of the fuel area and power plant. Here again, the comments were mostly about the size of the operations and the good working conditions. After the power plant tour, the group reconvened in the conference room of Building 80. 411082 0427 Industrial Hygiene Problems in Connection with Power Production S, A. Jones Early in our operations it became apparent that large quan tities of dust and water vapor were being lost to the atmosphere from lignite drying operations. Tests indicated that the condensed vapors were very acid and contained some lignite dust and ash. The sulfur content of the gases was relatively low as indicated by recording SO^ equipment located approximately one mile from the plant. The tests indicated that the dryer problem was primarily a visual one, but that good housekeeping practices necessitated their clean-up. Three pilot scrubbers were installed to check cleaning efficiency. As a result, a clean-up system for dryer stack discharge is in the design stage. In connection with lignite carbonization and tar production, large quantities of phenol-bearing, contaminated water is produced. The most effective system for cleaning up this contaminated water is one which combines the clean-up of the dryer exhaust stack and the contaminated water. In this procedure, the wastes from the lignite dryer and tar production are brought together and thoroughly mixed. The two waste materials compliment each other very well for disposal. The acid waterfrom the dryers is partially neutralized by thealkaline water from the tar string, and the phenols in the contaminated water from the tar string are absorbed by the lignite slurry from the dryers. 411082 0428 Rockdale's Medical Program - Dr. J. T. Richards Our medical program is three-fold in nature. Of greatest importance is the preplacement physical examination conducted on prospective employees. This examination includes X rays of the chest and lumbo sacral areas. It is amplified by urinalysis, serology, hemo globin, Rh factor and blood type. Prospective employees are told of minor defects for which they should go to their dentist or physician for correction. Of next greatest importance is the annual physical examination of employees. Laboratory work and chest X rays .are repeated. Again the employee is told of defects so that he can obtain corrective treatment. Our third major concern is treatment of injuries and the application of preventive medicine, which is on a day-to-day basis. A registered nurse and laboratory technicianare inattendance on the day shift. First aid menare in attendance during the afternoon and night shifts. Injuries requiring detailed or prolonged treatment are referred to hospitals having the necessary facilities and/ or specialists for care. Employees are given tetanus toxoid upon employ ment and at the time of their yearly physical. Equipment at the plant is adequate. The X-ray equipment is excellent and the laboratory is well equipped to perform the tests required. A satisfactory stock of ordinary medications is kept on hand for the treatment of minor illnesses. A small amount of plasma and infusion material is available forthe very occasional case which might 41'SS 0429 require this type of therapy prior to their arrival at a hospital. All X rays are examined by a consulting radiologist. Rockdale's Safety Program - W. G. Martin Our safetyprogram has three objectives. First, to prevent injury to the employee with the accompanying suffering and loss of earn ing capacity. Second, to prevent damage to equipment which frequently happens when there is a personal injury accident. Third, to prevent loss of production which occurs when an employee is not on a job and his portion of production remains unaccomplished. In helping to accomplish these objectives, safety engineering is of great importance. When a new piece of equipment is designed, safety features are designed into it as much as is possible. The em ployee is protected from open gears, belts, pulleys, etc. by adequate guards, and is furnished personal protective equipment if hazards exist which cannot be corrected by safeguards built into the equipment. Regular equipment inspection and preventive maintenance are consid ered a part of the program. Statistics are gathered and reports made and circulated on each accident that occurs in our plant. In analyzing our accident, statistics, we find that approximately 85 percent of all accidents are caused by the action of the employee himself; about 10 percent by mechanical failure; and the remaining 5 percent by acts of God. If accidents are to be eliminated, it is obvious that the employee himself is the one on which the greatest effort must be put forth. 411082 0430 Another means of promoting safety is our safety meetings. Regular meetings, which generally include a movie on some safety subject, are held for all departments. Safety contests, including awards for the winners, are also occasionally held. Plant publi cation and posters are also utilized to promote safety. Training of the employee is a most important phase of our safety program. This begins in the indoctrination meetings which each new employee attends and at which safety is stressed. When an employee is assigned to a job, the supervisor makes every effort to see that he is thoroughly trained, understands how the job should be done, and recognizee the hazards involved. Safety is considered the responsibility of many persons besides the safety director. Our program includes inspections such as mechanical, electrical, housekeeping, and fire prevention. Practically every type of personal protective equipment is made available to the employee. Danger tags and locks are used and extra instructions and examinations ure given operators of specialized equipment. Summarizing the entire program, we find that to obtain results, we must work directly with the employee. If we make the employee fully familiar with the hazards of his job, the cause of acci dent, the knowledge of how to prevent these accidents, and can instill in him the desire to work safely, we can feel that we have an effective safety program. 411082 0431 Discussion During the tour o the plant and during the discussion period which followed the planned program, there were several comments by the visitors. Some of the comments, which were all very favorable, were as follows: Mr. Wukasch statedthat the State group was very pleased to have the opportunity of sitting in on our meeting. He said that they we re all impressed with the openand above-board manner with which we had discussed our industrial hygiene problems with them, and with the progressive attitude of the Company in taking steps to eliminate the problems. He said that the knowledge they had gained of our operations and of our processes for preventing air pollution would be very helpful to them in discrediting wild tales about our operations, and would allow them to talk more intelligently with anyone making a complaint. He said that shortly after Alcoa began operations in Texas, they had received a letter from someone from the Northwest relative to the danger tc livestock and crops from aluminum smelting fumes and suggesting that steps be taken to prevent such occurrence here. He offered the assist ance of the department in connection with any problems which might develop, and felt that they were now in a much better position to be of help in solving them. Dr. Holle expressed appreciation that the Company had recognized its problems and was accepting its responsibility with resf act to industrial hygiene. He said that it is regrettable the less 411082 0432 responsible industry might force tough legislation which would be bad for industry in general. He gave credit to Alcoa for having repre sentatives at public health conferences and for voluntarily taking the lead in industrial hygiene matters in a community which had had little knowledge of industry. Dr. Holle said it was obvious that we were taking care of our employees on the job but wondered what means we had taken to interest them in safety at home. Mr. Harper told him ol' our programfor dispensing literature regarding safe practices at home. Judge Bell was also impressed with our approach to our problems. He stated that many companies withheld information from them, and working with them was therefore difficult. He said that hie group took the position that industry should make every effort to clean up objectionable emanations within the scope of economic operations and that all concerned would have to be satisfied with less than perfect elimination of the objectionable emanations. Dinner Dinner was lad at the Taylor Countrv Club. Here again the visitors comments were most favorable. The meeting broke up about 7: JO p. m. Conclusions It seems to be a rather general conclusion that the meeting was a success. The people from the State Health Department were 411082 0433 greatly impressed with the steps we had taken to solve our industrial hygiene problems, and felt that the knowledge they had gained would allow them to be helpful to us. For our part, we believe that we have obviously gained the goodwill of the State people and believe that they will cooperate with us in every way possible. August 5, 1955 H. A. Semken 411082 0434