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

An authorized employee is an employee who locks or tags machines or equipment in order to perform servicing or maintenance.

An energy-isolating device is considered capable of being locked out if it:

• Is designed with a hasp or other means of attachment to which a lock can be affixed.
• Has a locking mechanism built into it.
• Can be locked without dismantling, rebuilding, or replacing the energy-isolating device or permanently altering its energy control capability.

Something is energized if it is connected to an energy source or contains residual or stored energy.

An energy-isolating device is a mechanical device that physically prevents the transmission or release or 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.

An energy source is any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy.

A lockout device is a device that uses 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.

Normal production operations are the utilization of a machine or equipment to perform its intended production function.

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

Setting up is any work performed to prepare a machine or equipment to perform its normal production operation.

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

"Other employees" are all employees who are or may be in an area where energy control procedures may be utilized.