After isolating energy sources in a lockout/tagout procedure, which step follows?

• A. Verify zero energy before work
• B. Check energy sources again
• C. Apply lockout devices
• D. Notify supervisor

Answer: (C)

In lockout/tagout, isolating the energy sources is done to stop energy from reaching the equipment, but that isolation isn’t secure until someone physically prevents re-energizing. The next step is to apply lockout devices on every energy-control point. These devices hold the switches, valves, or breakers in the off position and prevent anyone from re-energizing the machine while work is being done. The lock gives the authorized worker control over the energy interruption and adds a clear, physical barrier to accidental startup. Tags may accompany the lockout to communicate information, but the lock itself is what provides the actual protection.

After the lockout is in place, verification steps like checking for zero energy or residual store energy are performed to confirm the system is truly de-energized, and any stored energy is safely released before work begins. Notifying a supervisor and other planning steps typically occur earlier in the process or as part of communication, but the immediate safe next action is applying the lockout devices.