What steps should be taken to verify a circuit is de-energized before work?

• A. Apply lockout/tagout, attempt to operate the switch to verify isolation, and measure zero voltage with an approved test instrument at the work location.
• B. Turn off the switch and assume isolation.
• C. Rely on a visual confirmation that the equipment is not energized.
• D. Use a non-approved tester to check for voltage

Answer: (C)

Verifying de-energization requires more than just looking at the equipment to see if it appears off. The safe approach is to first de-energize the circuit and apply lockout/tagout so no one can re-energize it while you work. Then, use an approved, properly rated voltage tester to confirm there is zero energy at the work location and at the disconnect, and check for any stored or residual energy in capacitors or other energy storage elements. Relying on a visual check can be misleading because energy may be present even when everything looks inactive, and backfeeds or other circuits can keep a path live. Using a tester that isn’t approved or rated for the circuit can give false readings or miss energized conditions, which is why only approved equipment should be used. Once zero voltage is verified with the correct instruments, you can safely begin work, keeping the lockout/tagout in place as required.