DEFINITIONS

LOCKOUT TAGOUT PROCEDURES AT THE WORKPLACE

To help you understand lockout/tagout and the requirements of the OSHA standard, here are some basic definitions:

Affected Employee: An employee whose job requires him or her to operate or use a machine or equipment on which service or maintenance is being performed under lockout/tagout or whose job requires him or her to work in an area in which such service or maintenance is being performed. Affected employees must be informed when lockout/tagout is being performed.

Authorized Employee: A person who locks and tags machines or equipment in order to perform service or maintenance on it.

Blanks: Typically, a metal disk that is inserted into the space between two pipe flanges. The blank is bolted in place and forms a solid block to prevent the passage of liquids or gases through the pipe. Blanking (the insertion of blanks) is an important step to assure the safe entry into tanks or vessels if the materials in the pipes pose a hazard to employees working inside.

Bleed: To release stored hydraulic, electrical, or pneumatic energy.

Block-Out: To physically prevent the movement of machinery or equipment using mechanical devices such as blocks, chains, cribbing, or timbers.

Capable of Being Locked Out: 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 are capable of being locked out if lockout can be achieved without the need to dismantle, rebuild or replace the energy-isolating device or to permanently alter its energy control capability.

Energized means connected to an energy source or containing residual or stored energy.

Energy Control: The use of energy-isolating devices to block or isolate energy sources as well as lockout/tagout procedures to prevent the unexpected startup or release of stored energy during maintenance or installation.

Energy isolating device means a mechanical device that physically prevents the transmission or release of energy such as a manually operated circuit breaker, a disconnect switch, a slide gate, a line valve, a block, and any similar device used to block or isolate energy. The term does not include a push-button, selector switch, or other control circuit type device.

Energy source means any source of electrical, mechanical, hydraulic, chemical, thermal or other energy.

Energy source menas any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal or other energy, including gravity.

Lockout device means 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.

Lockout means the placement of a lockout device on an energy isolating device ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed.

Lockout/Tagout Written Program: This is the main requirement of the OSHA standard. The written program provides details about the following:

  • The hazards of uncontrolled energy
  • Energy control and lockout/tagout procedures in the workplace
  • Complete records of all inspection and training that applies to energy control and lockout/tagout
  • Employee training
  • Inspections

Normal Production Operations: The use of a machine or piece of equipment to perform its intended production function

Servicing and/or Maintenance: Workplace activities that require lockout/tagout on the equipment before beginning the activity because employees may be exposed to the unexpected energization or startup of the equipment or the release of hazardous energy. Servicing and/or maintenance includes construction, installing, setting up, adjusting, inspecting, modifying, lubricating, cleaning or unjamming and making tool changes.

Setting Up: Any work performed to prepare a machine or piece of equipment to perform its normal production operation.

Tagout device means a prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.

Tagout means the placement of a tagout device on an energy isolating device to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.

Zero-Energy State: All energy has been controlled in the machinery or equipment