Lockout/Tagout: Who Owns the Lock

Lockout/tagout exists because machines start. Somebody presses a button, resets a breaker, or the equipment does it itself on a timer — and whoever has their hands inside pays for it.

The sequence

1. Prepare. Know every energy source: electrical, hydraulic, pneumatic, mechanical, thermal, chemical, gravity. Most machines have more than one. 2. Notify everyone affected before you shut it down. 3. Shut down using the normal stopping procedure. 4. Isolate every source — disconnects, valves, blocks. 5. Lock and tag each isolation point. 6. Release stored energy. Bleed pressure, discharge capacitors, block or lower suspended parts, let it cool. Stored energy is what catches people who did everything else right. 7. Verify. Try to start it. Then return the controls to off. This is the step people skip, and it is the only one that proves the rest worked.

One worker, one lock, one key

• Your lock. Your key. Nobody else's. If several people work on it, every one puts their own lock on, and the machine stays locked until the last one comes off.
• Only you remove your lock. The exception exists, it is rare, and it involves a documented procedure and management — not a supervisor with bolt cutters because you went home.
• A tag on its own is a sign, not a lock. Tagout alone is only acceptable where the equipment genuinely cannot be locked out, and it comes with extra precautions.

Who is who

Authorized employees do the lockout. Affected employees operate the equipment and must know when it is locked. Other employees just need to know never to touch a lock.

If you find a lock on something, you leave it. You do not need to know whose it is or why.

Before restart

Clear the tools, replace the guards, check nobody is in or near it, notify everyone, and only then remove locks and restore power.