What is the first critical step when performing Lockout/Tagout on equipment?

• A. Apply locks and tags immediately
• B. Notify supervisor after starting
• C. Identify all energy sources and verify that the equipment is de-energized before applying locks and tags
• D. Document the work order

Answer: (C)

Identifying all energy sources and confirming the equipment is fully de-energized before applying locks and tags sets the safety foundation for Lockout/Tagout. By listing every energy form—electrical, mechanical, hydraulic, pneumatic, chemical, thermal—and confirming how energy could reach the machine, you ensure there’s no stored or residual energy that could cause unexpected startup or energy release during service. Verifying de-energization with appropriate checks or testing methods then allows you to proceed safely to apply the locking devices and tags, knowing the equipment cannot be energized inadvertently.

Locking and tagging immediately without verifying that all energy sources are identified and de-energized can leave hidden energies active. Notifying supervisors after starting bypasses the necessary shutdown sequence, and documenting the work order, while important for records, does not establish a safe state for performing the maintenance.