Lockout/Tagout is the common name for a process of "Control of Hazardous Energy" as established by the Occupational Safety and Health Administration (OSHA) under Federal Registry 29 CFR 1910.147. The purpose of lockout/tagout is to prevent injury to persons during the repair, maintenance, inspection, and adjustment of equipment by controlling all energy sources used, stored, or produced by the equipment.

To lock out a machine or piece of equipment, all energy sources are turned off or disconnected, stored energy is released or restrained, and a lock is applied either directly to the disconnects of each energy source or through a lockout device affixed to each energy control device, so that re-energization cannot occur (Figure 1).

Figure 1  Lockout equipment ensures that equipment remains inoperable while adjustments or repairs are made.

Lockout/Tagout protects you from energy sources, such as moving machinery, and stored energy, including electrical, chemical, thermal, hydraulic, gravitational, and pneumatic.

1. Each authorized employee is issued separate locks and tags.
2. Locks and tags are standardized.
3. Use locks and tags only for LOTO.
4. Locks and tags have information about who placed them.
5. Only the person who placed the lock may remove it.
6. Authorized (qualified) employees are the only people allowed to lock and tag out equipment or machinery.
7. Know the equipment and energy sources.
8. Notify all affected employees that the machinery, equipment, or process will be out of service.
9. Conduct a normal shutdown. An orderly shutdown will be used to avoid any additional or increased hazards to employees as a result of equipment de-energization.
10. Machine or equipment isolation: Place all controls in "off" position and shut all control valves.
11. Place lockout/tagout device so that it will hold the energy isolating devices from the "safe" or "off" position.