Polychlorinated Biphenyls (PCBs) in Transit System Electrical Equipment

摘要

Polychlorinated Biphenyls (PCBs) belong to a family of organic chemicals known as chlorinated hydrocarbons. Used commercially in the United States since 1929, the manufacture of PCBs was prohibited by passage of the Toxic Substance Control Act (TSCA) in 1976. Under TSCA's mandate, the Environmental Protection Agency (EPA) has promulgated regulations severely restricting the processing, distribution, use, and disposal of PCB-containing materials. Over the years, PCB-containing fluids have been widely used as an insulating medium in electrical equipment because of their excellent dielectric, heat absorption, and fire resistant characteristics. This report presents the legislative history and current regulatory requirements concerning the continued use of PCBs in transit system electrical equipment. The recent rule-making by the EPA is presented in summary form to aid the reader in following the chronology of requirements affecting the continued operation, servicing, marking, and disposal of transit system electrical equipment which contains PCB materials. Types of transit system electrical equipment regulated by the EPA are identified and future regulatory requirements concerning allowable PCB concentration levels for specific electrical equipment are outlined. Transit system procedures for the handling of electrical equipment containing PCBs are presented and recommendations to assist transit systems in eliminating PCBs from electrical equipment are provided.