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Industrial hygiene summary report for workers exposed to polychlorinated biphenyls (PCB) in a capacitor manufacturing plant (plant 2; 1938-1977).

Nilsen NB; Waters MA; Prince MM; Zivkovich ZE; Ruder AM
Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, IWS 95-14, 2004 Mar; :1-223
This industrial hygiene summary report summarizes information about workers who manufactured large and small capacitors using polychlorinated biphenyls (PCBs) at a plant operating from 1938 through 1977. The first step in making a capacitor was to wind bales of foil and paper together tightly. This winding and the insertion of connecters was done automatically. Tops for the capacitors were assembled, and connectors were welded to the terminals of the capacitor tops. The assembled bale and capacitor top was then placed into the capacitor can and welded shut. There was a small opening in the top for filling with PCB oil: a process called impregnation. Trays of capacitors were placed into an impregnation oven heated to approximately 150 degrees C and brought under vacuum to remove all moisture from the capacitors before PCBs were pumped in. The impregnation cycle usually took place in a 200-gallon (800-liter) oven (30 ovens at this plant) at 150 degrees C for about 24-60 hours and a maximum of 125 hours depending on the size of the capacitors. Once impregnated, the capacitors were removed from the ovens dripping wet with PCBs, and transported by pushcarts to the "hot room" or the fill-hole soldering department where the impregnation hole was soldered shut by hand. Once the capacitors were dosed they were conveyed through a trichloroethylene degreaser to remove the excess oil and finally painted. Before packing and shipping, the capacitors were put through a heat test operation where possible cracks were spotted. The rejected capacitors were repaired or salvaged. Other types of non-PCB-filled capacitors (mica, electrolytic and tubular) were also manufactured before 1972. Exposures in the impregnation area were regulated for PCB exposure by only opening one or two impregnation ovens rather than all 30 ovens during a shift. Industrial hygiene controls included general ventilation or ceiling fans throughout the plant, and local exhaust ventilation for each of the 30 impregnation ovens. At the time of the NIOSH survey (1976), very few workers wore protective gloves, aprons, or safety glasses. PCB oil spills were found throughout the plant. The capacitor manufacturing process did not significantly change over the years. The use of PCB mixtures, commercially called Aroclors, changed over time. Aroclor 1254 was used from 1939 until a switch was made to Aroclor 1242, and finally Aroclor 1016 in 1976. The difference between the mixtures was the distribution of the chlorination of the congeners. The average chlorination for Aroc1ors 1242 and 1016 was 41-42%, and for Aroclor 1254 was 54%. A total of 104 department codes and 732 operation title codes were recorded, and a unique operation code was a combination of a department code and an operation code. All unique operations ever recorded at this plant were categorized into 29 categories based on inhalation and dermal exposure. The values for inhalation exposure were derived from the air concentrations measured at the plant in 1977. There was a potential for significant dermal exposure for some jobs. Dermal exposures were ordinally rated separately for each job and each category. Dermal exposures were in the same general magnitude as inhalation exposures. Both inhalation and dermal exposure estimates were used to develop a combination JEM.
Field-Study; Polychlorinated-biphenyls; Industrial-factory-workers; Industrial-hazards; Industrial-hygiene; Industrial-exposures; Workplace-studies; Work-operations; Electronic-devices; Electronics-industry; Exposure-assessment; Air-sampling
National Institute for Occupational Safety and Health, Division of Surveillance, Hazard Evaluations and Field Studies, Industrywide Studies Branch, Mail Stop R-13, 4676 Columbia Parkway, Cincinnati, OH 45226
12674-11-2; 53469-21-9; 11097-69-1
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Field Studies; Industry Wide
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National Institute for Occupational Safety and Health
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division