Prior to the ban on PCBs in the late 1970s, more than half of all PCBs manufactured in the United States were used as dielectric fluids and coolants in electrical equipment. Despite being banned by the Toxic Substances Control Act, PCBs already in use were permitted to remain in electrical equipment under a use exemption because they were not found to present an unreasonable risk to human health or the environment. It was assumed that the authorized equipment would be phased out over time from attrition; and, the industry, as a whole, has been retiring PCB-impacted equipment since then. However, much of this aging equipment is still in use today.
Transformers containing PCBs have been authorized for use for the remainder of their useful lives. However, transformers containing 500 parts per million (ppm) of PCBs or more (also known as “PCB transformers”) are subject to certain restrictions, such as prohibited use near food or feed locations or in/near commercial buildings. Other requirements include quarterly visual inspections, procedures to follow in the event of a leak, maintenance and reporting procedures, and provisions for protection to avoid transformer ruptures.
Prior to 1978, a vast majority of liquid-impregnated capacitors produced in the United States used PCBs as the dielectric fluid. Large capacitors that contain 1.36 kg or more of PCB dielectric fluid (also known as ”PCB capacitors”), are permitted for use for the rest of their useful lives as long as they are located in a restricted area. Large PCB capacitors that are not located in restricted areas are prohibited. All small capacitors (containing less than 1.36 kg of PCB dielectric fluid) may continue to be used for their remaining lives without access restrictions.
Electrical Light Ballasts
Non-leaking PCB and PCB-contaminated fluorescent light ballasts are permitted for use for the rest of their useful lives. When these ballasts are taken out of service, they must be disposed of properly as hazardous waste and are not to be sold to subsequent users.
Electromagnets, Switches, and Voltage Regulators
Most electromagnets, switches, and voltage regulators containing PCBs may continue to be used for their remaining useful or normal lives. The use or storage of a PCB electromagnet (500 ppm or more) in a location where human food or animal feed could be exposed to PCBs released from the electromagnet is prohibited.
Weekly inspections are required for electromagnets with PCBs if they are in use or stored for reuse and contain between 50 ppm and 500 ppm and pose an exposure risk to food or feed. No routine visual inspections are required for other PCB or PCB-contaminated (less than 500 ppm) electrical equipment in use or stored for re-use, but it is recommended that this equipment be inspected quarterly for leaks.