Which combination of actions best reduces the risk of electric shock when working on a circuit?

• A. Turn off the power on the circuit, tag, and lock the disconnect in OFF.
• B. Leave power on and inspect with high voltage tester.
• C. Use only PPE without turning off power.
• D. Rely on training without any de-energizing.

Answer: (A)

Preventing electric shock starts with removing the energy source from the circuit before you work on it. The approach that turns off the power, applies a tag, and locks the disconnect in OFF provides true control over the circuit and communicates clearly that maintenance is in progress. The lock physically prevents someone from re-energizing the circuit, while the tag warns others not to restore power until you’re done. This combination reduces the risk of unexpected energization and keeps you protected.

Leaving power on and inspecting with a high voltage tester still exposes live parts to shock risk. Relying on PPE alone doesn’t eliminate the energy source, so shocks could occur if insulation fails or the voltage is higher than expected. Relying on training without de-energizing offers no mechanism to prevent someone from turning the circuit back on while you’re working.