Lock Out / Tag Out system is a safety measure taken to protect workers from hazardous and dangerous machinery while under maintenance or out of order. A lockout is mandated by the Occupational Health and Safety Act (OSHA) in some countries.
If a hazardous or dangerous machine does not operate properly it needs to be tagged and locked in order to be isolated and hence ensuring safety of all workers. Tags and locks must be standard in colour and must provide adequate information about the lockout. Personal locks are placed on the tag and only the worker with the key can open it if necessary. If more than one worker uses the machine, all workers should place personal locks to ensure greater safety.
The locks and tags should be labeled with the name of the worker/s, the date and reason for lockout. It is imperative to ensure that the locks are secure enough to be able to sustain the hazardous environment. OSHA provides a step by step procedure that needs to be followed during and after the lockout.