Lockout–tagout

Lock out, tag out or lockout–tagout (LOTO) is a safety procedure used to ensure that dangerous equipment is properly shut off and not able to be started up again prior to the completion of maintenance or repair work.

It requires that hazardous energy sources be "isolated and rendered inoperative" before work is started on the equipment in question.

[citation needed] In the USA, the National Electric Code states that a safety/service disconnect must be installed within sight of serviceable equipment.

For example, a food processing plant may have input and output tanks and high-temperature cleaning systems connected, but not in the same room or area of the factory.

[citation needed] Safety equipment manufacturers provide a range of isolation devices specifically designed to fit various switches, valves and effectors.

[citation needed] When two or more people are working on the same or different parts of a larger overall system, there must be multiple holes to lock the device.

All Canadian health and safety legislation places a general duty on an employer to take all reasonable precautions and carrying out this standard of good practice is usually considered a mark of due diligence.

It also states that "Every employer shall ensure that where appropriate, work equipment is provided with a suitable means to isolate it from all its sources of energy.

This reinforces that employers should make all machinery safe for use, including adding additional precautions such as extra guards and safer PPE (Personal Protective Equipment).

The standard addresses practices and procedures necessary to disable machinery and prevent the release of potentially hazardous energy while maintenance or servicing activities are performed.

[11] The provisions of Part 1910.147 apply in conjunction with these machine-specific standards to assure that employees will be adequately protected against hazardous energy.

If employees service or maintain machines where the unexpected startup, energization, or the release of stored energy could cause injury, the OSHA standard applies, unless an equivalent level of protection can be proven.

Controlling hazardous energy in installations for the exclusive purpose of power generation, transmission, and distribution, including related equipment for communication or metering, is covered by 29 CFR 1910.269.