Lockout/Tagout Basics

Lockout/Tagout (LOTO) exists for one reason: to make sure a machine can't start up, release stored energy, or move while someone has their hands inside it. Skipping a step — even "just for a second" — is how amputations happen. It's also the single most common hazard OSHA's Amputation National Emphasis Program is looking for.

Energy isn't just electrical. Hydraulic pressure, pneumatic pressure, springs, gravity, and stored heat can all move a machine part with no warning. A LOTO procedure has to account for every energy source on that equipment, not just the main power switch.

Key points

• Identify every energy source on the equipment before you start — electrical, hydraulic, pneumatic, mechanical, and gravity.
• Shut down the equipment using the normal stopping procedure, then isolate every energy source you identified.
• Apply your own lock and tag to each isolation point. Never work under someone else's lock.
• After locking out, try to start the equipment (a "zero energy check") to confirm it's actually isolated before you begin work.
• Only the person who applied a lock removes it — no exceptions, even if they've left for the day.
• If more than one person is working on the same equipment, each person applies their own lock (a group lockout device if needed).

Discussion questions

• Can anyone name an energy source on our equipment besides the main electrical switch?
• Has anyone ever been tempted to skip a lockout step because the job seemed quick? What happened, or what could have happened?
• Do we know where the lockout devices and tags are kept for the equipment we run?