Lockout/Tagout (LOTO) is OSHA's most-cited standard year after year, yet violations are entirely preventable. A proper LOTO program costs almost nothing to implement and prevents amputations and electrocutions — the most severe injuries in manufacturing.
The Core Principle
Before any servicing or maintenance of machinery where unexpected energization or startup could cause injury, the machine must be isolated from its energy sources and locked out. Only the worker performing the service should hold the key to the lock. No lock, no work. This applies to electrical, pneumatic, hydraulic, mechanical, thermal, and chemical energy sources.
The Six Steps
1. Notify affected employees that LOTO is required. 2. Shut down the machine using normal procedures. 3. Isolate all energy sources — disconnect electrical, release pneumatic pressure, block mechanical movement, bleed remaining hydraulic pressure. 4. Apply lockout devices to each energy isolating device. 5. Release or restrain stored energy — bleed pipes, block falling parts, release springs. 6. Verify zero energy by attempting to start the machine and testing for movement.
Group Lockout
When multiple workers service the same machine, each worker applies their own personal lock to a hasp that secures all energy isolating points. This ensures no single worker can be locked out alone. The employer must provide enough locks and hasps for all workers involved in a group lockout.