Hazardous Energy Control - Lockout/Tagout

The Hazardous Energy Control – Lockout/Tagout Program is designed to prevent injuries resulting from unexpected start-up, energization or release of stored energy during servicing and maintenance of equipment.

Hazardous energy, such as electricity, chemical, radiation, pneumatic, hydraulic, mechanical and gravitational energy sources, must be dissipated and isolated before servicing or maintaining equipment. Physical controls are generally known as Lockout/Tagout, or LOTO, and consist of locks and tags applied to the energy-isolating device of the hazardous energy source.

The Hazardous Energy Control – Lockout/Tagout (LOTO) program requires you to:

  • Develop a formal, written LOTO program that defines the program’s requirements, and identifies specific activities where the use of LOTO is required or exempted.
  • Develop equipment-specific energy control procedures and annual inspection requirements.
  • Ensure equipment can accept OSHA-approved LOTO devices and that these devices are readily available.
  • Define roles and responsibilities for implementing the LOTO program.
  • Ensure personnel in the LOTO program are trained.
  • Enforce the program to ensure hazardous energy is controlled during work.

The Hazardous Energy Control – Lockout/Tagout (LOTO) Program applies to all University organizational units at all locations including the Seattle campus, UW Bothell, UW Tacoma, UW Medical Center, Harborview Medical Center, University-owned property University-leased space and temporary field locations under the control of University operations staff.

Each campus, organizational unit or department is responsible for developing its own LOTO program.

What you need to know

What you can do to stay safe

Authorized personnel:

  • Always communicate and coordinate LOTO work with affected personnel, and others as needed.
  • Always follow LOTO procedures when working on applicable equipment.
  • Suggest changes to LOTO procedures that need improvement for safety reasons.
  • Report equipment that does not have LOTO procedures and may pose a hazard.
  • Report all incidents and near misses involving the release of hazardous energy to your supervisor immediately, and to EH&S using the Online Accident Reporting System (OARS).
  • Contact EH&S for advice or information.

Employees, students and visitors, including affected personnel:

  • Ask questions if unclear about the LOTO program and procedures and how it affects your work area.
  • Know what equipment in the area needs to be maintained and serviced using LOTO procedures.
  • Know who are the authorized personnel for your area.
  • Never touch or try to start up equipment that has been locked and tagged out, and tell others as needed.
  • Ask about equipment that does not have LOTO procedures and you think may pose a hazard.
  • Understand and follow instructions from authorized personnel.
  • Report all incidents and near misses involving the release of hazardous energy to your supervisor immediately, and to EH&S using the Online Accident Reporting System (OARS).
  • Contact EH&S for advice or information.

Services available

EH&S provides consultation and assistance to departments to comply with the requirements of the LOTO program, and provide or coordinate LOTO training to Authorized Personnel.

LOTO equipment resources are available through UW Procurement Services.

Frequently Asked Questions (FAQ)

Injuries depend on the type of hazardous energy and the degree of exposure, but may include lacerations, crushed or fractured body parts, amputations, cuts, burns, electrocution or fatalities.

All hazardous energy control procedures are to be inspected at least annually by another authorized person that is not involved in the LOTO.

Tagout devices may be used only if the employer can demonstrate that its tagout program provides "full employee protection," as required by §1910.147(c)(3). Additional safety measures for the tagout ("Tags Plus") are mandated, given the inherent limitations of a tag, in order to achieve a level of safety that is equivalent to that which would be achieved through a lockout system. In other words, you must implement additional safety measures that "bridge the gap" between the degree of safety achieved through lockout and the degree of safety achieved through tagout.  An additional safety measure could be removing the fuse in addition to the tagout device

More information


Individual who is required to operate, use or be in the area where a machine or equipment could be locked or tagged out for service or maintenance. Affected personnel are not authorized to perform lockout/tagout.

Individual who is qualified by proper training and has been given the authority and responsibility to perform a specific lockout/tagout-related task by his or her supervisor. Such authority and responsibility includes de-activating and locking out equipment and systems in compliance with this program.

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 built-in locking mechanism
  • Can be locked without dismantling, rebuilding, or replacing the energy-isolating device or permanently altering its energy control capability

A designated Authorized Person responsible for the exclusive control of energy isolating devices installed on an electrical utility system. Please refer to Section XV of the Facilities Services Lockout/Tagout Safety Program for more information.

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

A mechanical device that physically prevents the transmission or release of energy. This includes, but is not limited to:

  • Manually operated electrical circuit breakers
  • Disconnect switches
  • Manually operated switches that disconnect the conductors of a circuit from all ungrounded supply conductors if no pole of the switch can be operated independently
  • Line valves
  • Blanks, blinds, blocks or similar devices that are used to block or isolate energy
  • Removal of wires or sections of pipe
  • Installation of blocks, wedges and cribbing
  • Similar devices 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.

A lock used to prevent the unauthorized operation of equipment. Equipment protection locks are not considered lockout devices.

A method of maintaining a lockout/tagout procedure when more than one person is involved. The lock box is used to store any keys used in the lockout/tagout procedure until the job is complete.

A group lockout/tagout device able to accept multiple locks and tags. The device is secured to energy isolating controls or devices and has multiple points of attachment for locks and tags.

Energy that could cause harm to personnel, such as electricity, high-intensity electromagnetic fields, and chemical, radiation and mechanical sources. Mechanical sources of energy include gravity, pneumatic, hydraulic, compression, spring tension and pressurized systems.

A procedure that involves welding on pressurized pipelines, vessels or tanks to install connections or accessories. The procedure is commonly used to replace or add sections of pipeline used in air, gas, water, steam and chemical distribution systems without interrupting service.

An authorized faculty, staff, employee or student who has overall responsibility for meeting the requirements of the lockout/tagout procedures when working in a group. The Primary Authorized Person will attach a lock and tag when the equipment is de-energized before work begins and will be the last person to remove their lock and tag when the job is completed.

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

Any device that uses positive means, such as a lock, blank flanges and bolted slip blinds, to hold an energy-isolating device in a safe position, thereby preventing the energizing of machinery or equipment.

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

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.

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