Before working on an electric cargo winch master switch or controller, what should be done?

Correct Answer: Option B — open the circuit breaker in the power supply and tag-out

Safety protocols for working on electrical equipment require total isolation from the power source. Opening the circuit breaker and applying a lockout/tag-out device ensures that the equipment cannot be energized accidentally while personnel are working on the internal components, adhering to strict OSHA and USCG safety management system requirements.