Why Lockout-Tagout Exists at All
Lockout-tagout protects against one thing: a machine that is off but not safe. Stored pressure, a capacitor, a raised load, or a colleague who does not know anyone is inside can all restore energy to equipment that appears dead. The procedure isolates every energy source, locks each isolation point, and then requires a verified attempt to start before any work begins.
The verification step is the one that gets skipped and the one that does the work. Locking out is visible and social; trying to start the machine afterwards feels redundant to someone who has just fitted the lock. Every serious incident in this area happens in the gap between isolation and proof of isolation. One thing to keep off screen is machine-specific detail: isolation point locations, valve numbering, and stored-energy values belong on the equipment placard, not in general training that will be watched by people working on different assets.
The procedure is set out across ten scenes: two on why off does not mean safe, two on identifying every energy source including stored energy, two walking isolation and lock application in order, one on the try-out verification, one on group lockout and shift handover, one on the rules for lock removal, and one on returning the machine to service.
