Which sequence correctly describes a proper lockout/tagout procedure before maintenance on energized equipment?

• A. De-energize the equipment, remove all tags, remove locks, restart equipment.
• B. De-energize the equipment, isolate energy sources, apply approved lockout devices, attach warning tags, verify the zero-energy state, perform the work, remove tools and testing measurements, then remove locks and restore energy following established protocol.
• C. Apply lockout devices, then de-energize, attach tags, and test.
• D. Verify zero-energy, then de-energize, isolate energy sources, remove locks.

Answer: (B)

The key idea is to keep the equipment safely isolated from all energy sources so maintenance can be performed without the risk of unexpected energizing. The proper sequence starts by removing all energy from the system and then preventing any re-energization: first de-energize the equipment, then isolate the energy sources, apply approved lockout devices, attach warning tags, verify that the system is truly in a zero-energy state, perform the maintenance, remove any tools or testing devices, and finally remove the locks and restore energy following the established protocol. This order matters because locking out the energy sources physically prevents re-energizing, while tagging communicates that a lockout is in place and who is responsible. Verifying zero energy confirms there’s no stored or residual energy left before work begins, ensuring a safe workspace. The other options skip essential steps, place steps in unsafe order, or omit verification and proper lockout, which can allow energization to occur unexpectedly and create a serious hazard.