Glossary - OSHA-ANSI Lockout/Tagout (LOTO) Certificate Training

An employee whose job requires them to operate or use a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or whose job requires them to work in an area in which such servicing or maintenance is being performed.

A person who locks out or tags out machines or equipment to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section.

Control strategies other than traditional lockout/tagout (LOTO), recognized by the 2024 ANSI standard as co-equal options if they provide effective risk reduction.

An energy-isolating device is capable of being locked out if it has a hasp or other means of attachment to which, or through which, a lock can be affixed, or if it has a locking mechanism built into it. Other energy-isolating devices can be locked out if lockout can be achieved without dismantling, rebuilding, or replacing the energy-isolating device, or permanently altering its energy-control capability.

A scenario involving multiple energy sources or workers that requires coordinated control measures.

Measures taken to protect digital control systems from unauthorized access or unintended energization through networked or electronic devices.

Connected to an energy source or containing residual or stored energy.

A mechanical device that physically prevents the transmission or release of energy, including but not limited to the following: A manually operated electrical circuit breaker; a disconnect switch; a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors, and, in addition, no pole can be operated independently; a line valve; a block; and any similar device used to block or isolate energy. Push buttons, selector switches, and other control circuit-type devices are not energy-isolating devices.

Any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy.

Risk mitigation measures that are practical and effective in reducing hazardous energy exposure to an acceptable level.

A lockout/tagout arrangement where multiple employees work on the same equipment and each maintains personal control over energy isolation.

Any energy source (electrical, mechanical, hydraulic, pneumatic, chemical, thermal, etc.) that could cause injury if uncontrolled during servicing or maintenance.

A procedure used in repair, maintenance, and service activities that involves welding on a piece of equipment (pipelines, vessels, or tanks) under pressure to install connections or appurtenances. It is commonly used to replace or add sections of pipeline without interrupting service in air, gas, water, steam, and petrochemical distribution systems.

The placement of a lockout device on an energy-isolating device, in accordance with an established procedure, ensures that the energy-isolating device and the controlled equipment cannot be operated until the lockout device is removed.

A device that utilizes a positive means, such as a lock, either key or combination type, to hold an energy isolating device in the safe position and prevent the energizing of a machine or equipment. Included are blank flanges and bolted slip blinds.

The utilization of a machine or equipment to perform its intended production function.

Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, maintaining, and/or servicing machines or equipment. These activities include lubrication, cleaning or unjamming of machines or equipment, and making adjustments or tool changes, where the employee may be exposed to unexpected energization or start-up of the equipment, or the release of hazardous energy.

Any work performed to prepare a machine or equipment to perform its normal production operation.

Residual energy present in equipment or processes after shutdown, such as pressurized fluids, springs, elevated weights, or charged capacitors.

The placement of a tagout device on an energy-isolating device, in accordance with an established procedure, to indicate that the energy-isolating device and the equipment being controlled may not be operated until the tagout device is removed.

A prominent warning device, such as a tag and a means of attachment, that can be securely fastened to an energy-isolating device in accordance with an established procedure, to indicate that the energy-isolating device and the equipment being controlled may not be operated until the tagout device is removed.

The process of confirming that energy sources have been effectively isolated before beginning work on equipment, typically by attempting to operate the controls safely.

Machinery or systems are divided into sections or zones, each of which can be controlled separately to improve safety and energy efficiency.