Lockout-tagout

Lockout-tagout (LOTO) or lock and tag is a safety procedure which is used in industry and research settings to ensure that dangerous machines are properly shut off and not able to be started up again prior to the completion of maintenance or servicing work. It requires that hazardous energy sources be "isolated and rendered inoperative" before work is started on the equipment in question. The isolated power sources are then locked and a tag is placed on the lock identifying the worker who has placed it. The worker then holds the key for the lock ensuring that only he or she can start the machine. This prevents accidental startup of a machine while it is in a hazardous state or while a worker is in direct contact with it.

Lockout-tagout is used across industries as a safe method of working on hazardous equipment and is mandated by law in some countries.

When two or more people are working on the same or different parts of a larger overall system, there must be multiple holes in which to lockout the device. To expand the number of available holes, the locked-out device is first secured with a folding scissors clamp that has many padlock holes capable of keeping it closed. Each worker applies their own padlock to the clamp. The locked-out device cannot be activated until all workers have removed their padlock from the clamp.

In the United States a lock selected by color, shape or size (e.g. red padlock) is used to designate a standard safety device, locking and securing hazardous energy. No two keys or locks should ever be the same. A person's lock and tag must only be removed by the individual who installed the lock and tag unless removal is accomplished under the direction of the employer. Employer procedures and training for such removal must have been developed, documented and incorporated into the employer energy control program.

Lockout-tagout in the US, has 5 required components to be fully compliant with OSHA law. The 5 components are: 1. Lockout-Tagout Procedures 2. Lockout-Tagout Training (for authorized employees and affected employees) 3. Lockout-Tagout Policy (often referred to as a program) 4. Lockout-Tagout Devices and Locks 5. Lockout-Tagout Auditing - Every 12 months, every procedure must be reviewed as well as a review of authorized employees

Modern machinery can contain many hazards to workers, examples of the most common risks are:

For example, an average industrial device may contain things such as hot fluids, moving presses, blades, propellers, electrical heaters, conveyor belts with pinch points, moving chains, ultraviolet light, etc.

Disconnecting or making safe the equipment involves the removal of all energy sources and is known as isolation. The steps necessary to isolate equipment are often documented in an isolation procedure or a lockout tagout procedure. The isolation procedure generally includes the following tasks:

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