OHST Practice Exam 2026 – The Comprehensive All-in-One Guide to Exam Success!

The most likely electrical devices to contain polychlorinated biphenyls (PCBs) are transformers, capacitors, and fluorescent light ballasts. PCBs were widely used in electrical equipment due to their insulating and cooling properties. Transformers and capacitors often require liquid insulation, and historically, PCB oils were used until they were banned or restricted in many countries due to environmental and health concerns. Fluorescent light ballasts also sometimes contained PCBs as a part of the materials used in their construction.

This makes the identification of the correct devices pivotal in understanding where PCBs might still be present in older equipment, particularly in industrial and commercial applications where such devices were common. Awareness of these potential sources is crucial for proper safety protocols and environmental management strategies when handling or disposing of electrical equipment.