Document 10N43y4YepMZBjXKzkb7yOKvK

* >% - r" Vinyl Chloride Job Health Hazard Series U.S. Department of Labor Occupational Safety and Health Administration June 1975 OSHA 2225 CTL032564 About This Pamphlet The purpose of this pamphlet is to give employees, as well as the gen eral public, an overview of the dan gers involved in working with vinyl chloride (VC) and to explain the OSHA standards that apply to its use in the workplace. Vinyl chloride is the basic ingre dient in making polyvinyl chloride (PVC), which is used in about 55 percent of today's plastic products. Assuch.it isan important element in today's technology and economy. It is possible to work with these sub stances in a manner that will not cause illness. But doing so requires an understanding of the hazards in volved and of the measures neces sary to eliminate or reduce these hazards. The following pamphlet contains general information only. It should not be considered a substitute for any of the provisions of the Occupa tional Safety and Health Act or for any regulations issued by the U. S. Department of Labor's Occupa tional Safety and Health Administra tion. Vinyl Chloride Job Health Hazard Series U.S. Department of Labor Occupational Safety and Health Administration June 1975 OSHA 2225 CTL032565 Endanger d Work rs Mostjob health hazards--such as lead, mercury, and silica--have been recognized for decades or centuries. But vinyl chloride, a gas used in the production of more than half of today's plastic prod ucts, has only recently been shown to be highly dangerous. Until January 1974, the gas was generally considered of low toxicity. Then it was found to cause a rare form of cancer of the liver--angiosarcoma--which cannot be diagnosed until it is incur able. Vinyl chloride (VC), which has always been handled with rela tive care, since it is both explosive and highly flammable, is the basic ingredient in making polyvinyl chloride (PVC). PVC is all around us. The chances are you ride to work on a vinyl seat, walk across vinyl-tiled floors on PVC-soled shoes, eat sandwiches wrapped in PVC from a vinyl tablecloth, relax to the sound of PVC records. Infants suck on PVC pacifiers. Although studies are continuing in both government and private laboratories, no one has yet discovered any danger in these finished products. By the time the plastics reach this stage, most of the vinyl chloride has been chemically locked into the PVC and will not come out again. The danger comes during the production process. Three basic steps are necessary to the production of vinyl products. First the vinyl chloride, or "monomer," is produced in a closed process, usually involving a reaction between ethylene and chlorine. The VC monomer is shipped as a compressed, liquefied gas to plants that produce the PVC resin. Batches of VC are "polymerized" by mixing them with catalysts in giant vats or reactors. After drying, the PVC resins are compounded by the addition of stablizers. lubricants, and plasticizers. Before being shipped to fabrication plants, the resin may be converted to pellets, powders, pastes, or film. The fabrication end of the PVC industry covers a huge range of processes in which the PVC is turned into its myriad of finished products. In the United States there are 15 monomer plants employing about 1,000 workers, 36 PVC plants with 5,600 workers, and some 7,500 fabrication plants with about 350,000 employees. At each stage there are certain potential trouble spots where the VC gas may escape into the air and reach the workers. V^w.. TL032 566 Both monomer and polymerization plants face the problems of random leaks from pump seals, compressors, valves, gaskets, and storage tanks. Both must also deal with reducing the amount of the gas that escapes during quality control sampling. During loading or unloading of the monomer, tank car workers ma^ be exposed to high concentrations in the air. Because of the danger from fire and explosion, the plants are usually spread over sites of several acres, with the result that the VC gas is not confined to small areas, but often can be found in low levels throughout the plant. Most plants that produce the basic monomer are open-air opera tions and generally have lower concentrations ofgas in the air than polymerization plants. The highest exposures in the entire industry apparently are those experienced by the workers who climb into the polymeriza tion vats or reactors to chip out the PVC residue. In the past, these cleaners were surrounded by concentrations as high as 1,600 parts of VC per million parts of air; exposure levels for reactor cleaners still may reach 500 parts per million (ppm). Fourteen of the 16 men who have died from VC-related angiosarcoma in the United States had, at one time or another, been vat cleaners. By the time the PVC reaches the fabricating plant, the danger is the small amount of VC gas that was not chemically locked into the PVC. These may leak out ofthe PVC in processing or handling. The fabrication procedures that hold the most potential for expo sure involve mixing and heating the resin, as in extruding PVC around an electrical wire. The heat may drive offany remaining gas into the workplace air. What It Can Do to You In addition to the danger of angiosarcoma of the liver, recent studies of workers exposed to VC show that they have higher than normal rates of cancer of the lung, brain, and bone marrow. Suicide rates were found to be twice normal in one study of 161 workers in a Kentucky plant. Vinyl chloride's attacks are slow; the cancers, for example, may not show any symptoms until 15 years after the beginning of a worker's exposure. Pr vention of Vinyl Chi rid Poisoning The basic protection from VC must come from engineering con trols: avoiding leakage of the gas into the air. Under the Occupa tional Safety and Health Act, this is the responsibility of em ployers, many of whom have expressed doubts about being able to meet the stringent OSHA standard ofone part per million of VC in the air, averaged over an 8-hour day, with a maximum peak of five ppm. If these limits are not met, employers must reduce exposures to the "lowest practicable level." and personal respirators must be made available to the employees who are exposed. In certain situations, employees have a choice as to whether or not to wear respirators. Until April I, 1976, a worker can decline to wear a respirator when the VC concentrations are above one ppm but not above 25 ppm. Federal Standards for Vinyl Chloride Exposure The OSHA standard for vinyl chloride exposure, although prom ulgated in October 1974, to take effect January I, 1975, was held in abeyance pending action on a suit brought by the plastics manufac turers. Under a decision by a special three-judge panel of the United States Second Circuit Court, the standard went into effect April 1, 1975. The plastics manufacturers have *ndicated that they intend to appeal this decision to the U. S. Supreme Court. The standard applies to the "manufacture, reaction, packaging, storage, handling or use ofVC and PVC' * but not to the handling or use of finished PVC products. PVCJs. considered a "finished product" when it has passed through.all production steps that involve mass melting. The standard, for example, would cover such operations as molding, extrusion, banbury mixing, and calendering. It would not cover thermoforming or blister packag ing. Although the standard sets an air concentration limit ofone ppm cTL032567 of vinyl chloride on an average over an 8-hour workday, and a five ppm allowable peak exposure, it sets no deadlines for manufactur ers to reach such levels. The technology involved is too uncertain. But the employers must draw up plans for reaching the standard levels, anJntake those plans availableJo^OSHA. ~ Because of the wide variety of types of plants involved in polyvinyl chloride production, the concept of an "action level" has been made part of the standard. Jf afabricating.plant tests its air and finds that VC levels are less than 0.5 ppm ("action level"), the plant is effectively exempted from much of the rest of the standard. If less than 0.5 ppm is in the air, the employer is exempted from further monitoring unless changes are made in the processing, or there is other reason to believe the levels may have risen. When the monitoring reveals VC levels above one ppm, the employer must set up a regulated area within the plant--that area in which the dangerous amounts are found--and restrict it to "authorized personnel." A daily roster of Such persons within the area must be maintained. Employees must be informed of the cancer risk associated with VC, instructed in the proper use of respirators, and made aware of work practices that could release dangerous quantities of the gas. All employees exposed to levels higher than 0.5 ppm, whether they wear respirators or not, must be given free medical examina tions, including blood tests, once a year. Workers with more than. 10 years exposure must be examined every 6 months. Records of exposure must be kept for at least .30 years, and the results made available to employees or their authorized represen tatives. Medical records must be held 30 years, or 20 years after employment, whichever is longer. Copies of medical records must be furnished to a physician on request of the employee. Warning signs in regulated areas and labels on VC and un finished PVC containers must include the words "cancer-suspect agent." U.S. DEPARTMENT OF LABOR Regional Offices for Occupati nal Safety and Health REGION I (CT, ME, MA, NH, Rl, VT) 18 Oliver Street Boston, MA 02110 Telephone: (617) 223-6712 REGION II (NY, NJ, PR. VI, CZ) Room 3445, 1 Astor Plaza 1515 Broadway New York. NY 10036 Telephone: (212) 971-5941 REGION III (DE, DC, MD, PA, VA, WV) ^ 15220 Gateway Center 3535 Market Street Phlladephia, PA 19104 Telephone: (215) 597-1201 REGION IV (AL, FL, GA, KY, MS, NC, SC, TN) 1375 Peachtree Street, N.E. Suite 587 Atlanta. GA 30309 Telephone: (404) 526-3573 REGION V (IL, IN, MN, Ml, OH, Wl) 230 South Dearborn 32nd Floor Chicago. IL 60604 Telephone: (312) 353-4716 REGION VI (AR, LA, NM, OK, TX) 555 Griffin Square Room 602 Dallas, TX 75202 Telephone: (214) 749-2477 CTL032568 HtUIUN VII (IA, Kb, MU, Nt) 911 Walnut Street, Room 3000 Kansas City, MO 64106 Telephone: (816) 374-5861 REGION VIII (CO, MT, ND, SD, UT, WY) Room 15010, Federal Bldg. 1961 Stout Street Denver, CO 80202 Telephone: (303) 837-3883 REGION IX (CA, AZ, NV, HI) Box 36017 450 Golden Gate Avenue San Francisco, CA 94102 Telephone: (415) 556-0586 REGION X (AK, ID, OR, WA) Federal Oflice Bldg , Room 6046 909 First Avenue Seattle, WA 98174 Telephone: (206) 442-5930 CTL032569 j O 3 * UO) N) tn vj o ] '3 ( f