List Of Documents and Appendices:

Applies to: 

  • Authorized Employees – Those who perform service or maintenance on equipment that could inadvertently be turned on or operated or could release hazardous energy
  • Affected Employees – Those who operate or could inadvertently operate equipment being worked on
  • Supervisors of Authorized and Affected Employees

Does not apply to: 

  • Users of plug and cord electrical equipment

1.0 Introduction

The lockout/tagout procedure provides guidelines to ensure individual safety of personnel servicing and maintaining equipment by preventing the inadvertent operation of equipment and providing protection from stored energy through the control of hazardous energy. Refer to 29CFR1910.147 and §.269 for regulatory guidance.

2.0 Definitions (Appendix A)

Affected employee

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.

Authorized employee

A person who locks out or tags out machines or equipment in order 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 procedure.


Free from any electrical connection to a source of potential difference and from electrical charge.

Energy Sources

Examples of energy sources that are applicable are electrical hydraulic, pneumatic, thermal, process gases and fluids, chemical, and mechanical.

Energy isolating device

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


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


A secure box used to store one or more keys to locks on isolation devices during group lockout. The lockbox allows Authorized Employees to install their personal locks on the box preventing access to the isolation locks’ keys.


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

Lockout device

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. Locks should be singularly keyed.

Other Employee

Employees whose work operations are or may be in an area where energy control procedures may be utilized.

Personal Lock

Lock installed by an authorized employee on an isolation device or lockbox for personal protection while servicing or maintaining equipment.  The key to this lock is maintained by the authorized employee installing the lock.  The lock shall be singularly keyed.

Servicing and/or maintenance

Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, and 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 the unexpected energization or startup of the equipment or release of hazardous energy

Supervisor’s or Operations Lockout device

(For group lockout). The purpose of this lock is to allow the Supervisor or Operations to manage items that are locked/tagged out and is not intended for personal protection.    This lock is applied by a Supervisor or Operations personnel to the lockbox after equipment has been lockout/tagout by an authorized employee at the isolation devices.  The control of the key is maintained by the Supervisor or Operations.   This lock can be removed by employees of equal or greater authority,


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.

Tagout device

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 the equipment being controlled may not be operated until the tagout device is removed.

3.0 Responsibilities

  • Departments and Supervisors shall be responsible for developing and using of lockout/tagout procedures and ensuring employee training is completed.
  • Departments should ensure that equipment specific procedures are developed, and inspected periodically (at least annually).
  • Employees are required to use lockout/tagout procedures to control hazardous energies and complete required training.
  • Contractors are required to have a company Energy Control program.
  • Non-NCSU personnel will receive information about lockout/tagout policies affecting their procedures from the department hiring the contractor.

4.0 General Requirements

  • Lockout is the preferred method of isolation.
  • A tagout system for isolation requires a written procedure, supervisor approval, and may be used only when an energy isolating device cannot be locked.
  • Do not attempt to operate any switch, valve, or energy isolating device when the device is locked/tagged out.

5.0 Sequence of Lockout/Tagout and Release to Normal Operations –
Authorized Employees

  1. Identify equipment needing lockout/tagout. Identify all energy sources (e.g. electrical, mechanical, pneumatic, chemical, thermal, and radioactive, etc.)
  2. Notify all affected employees that a lockout/tagout system is to be utilized. The authorized employee shall know the type and magnitude of energy that the machine or equipment uses and shall understand the hazards
  3. If the machine or equipment is operating, shutdown by the normal stopping procedure (depress stop button, open toggle switch, etc.).
  4. Properly position the switch, valve, or other energy isolating device(s) to put the device in a “safe” position. Dissipate, deactivate or restrain stored energy (such as springs, elevated machine members, rotating flywheels, hydraulic systems, and air, gas, steam, or water pressure, etc.) by methods such as repositioning, blocking, bleeding down, etc.
  5. Lockout/tagout each energy isolating devices with a singularly keyed lock. Attempt to start the machine or equipment to make certain the equipment will not operate. This can be done after each lock is applied but must be done after all locks have been applied.
  6. Caution: Return operating control(s) to “neutral” or “off” position after the test.
  7. The equipment is now locked/tagged out. The key for the lock must be under the control of the authorized employee who installed the lock(s).
  8. After completing the service or maintenance and determining the equipment is ready for normal production operations, remove all tools, reinstall guards, and ensure affected and authorized employees are in the clear.
  9. Remove all locks. Each lock shall be removed from each energy isolating device by the authorized employee who applied the lock. Operate the energy isolating devices to restore energy to the machine and equipment. Exceptions To Standard Removal of Locks are in mandatory Appendix B.

6.0 Group Lockout/Tagout

Group lockout/tagout is used to protect multiple authorized employees. Every employee who could be exposed to inadvertent re-energization shall apply their own lock to the group lockout.

6.1 Group Lockout at the Specific Piece of Equipment – Single Isolation Device

  1. After the equipment is deenergized following Steps 1-4 in Section 5.0 above, the authorized employee may install a hasp or other device that accepts multiple locks, and installs a personal lock. The authorized employee shall then attempt to start the machine or equipment to make certain the equipment will not operate.
  2. Each authorized employee then attaches his or her lock to the hasp for personal protection.
  3. As each Authorized Employee no longer needs to maintain lockout protection, he or she can remove their lock.
  4. After all locks are removed from the hasp, the authorized employee may remove the hasp and reenergize the equipment.

6.2 Group Lockout Using A Lockbox – Multiple Isolation Devices

  1. After the equipment is deenergized following Steps 1-5 in Section 5.0 above, for all isolation points, the authorized employee places the keys to all lockout devices into a Lock Box.
  2. The authorized employee whose keys are in the lock box attaches an Operations Lock to the Lock Box to control access. The authorized employee can then retain possession of the key to the Operations Lock or may transfer possession to an operator (authorized employee) or supervisor of equal or greater authority according to the written procedure.
  3. Each Authorized employee then attaches a personal lock on the lock box for personal protection. Authorized employees will remove individual locks when their work is completed.
  4. After all authorized employees have removed their personal locks, the Operations Lock will be removed by the authorized employee who installed it; or by the operator or supervisor authorized to remove it.
  5. At this time, the isolating device locks can be removed from each energy isolating device by the authorized employee who applied them, according to the written procedure, and the equipment can be energized.

7.0 Equipment Specific Energy Control Procedures

Each department shall document the steps required to control hazardous energies. (See Appendix C for examples). The following steps should be included in the written procedure.

  • Specific statement of the intended use of the procedure
  • Specific procedural steps for shutting down, isolating, blocking and securing machines or equipment to control hazardous energy
    • List all energy sources by type and location
    • List all energy isolation devices by type and location
    • For each energy isolation device, describe the type of lockout device required
  • Specific procedural steps for the placement, of lockout devices
    • Describe the order the isolation devices are to be actuated, what the neutral or deenergized position is (open, closed, up, down, on, off, )
    • Describe what the group lockout procedure is, if any. Will there be a lockbox or hasp on each isolation device? Will there be an Operations or Supervisor’s lock?
    • List specific Energy Control Lock/Tag Number placed on the isolation devices
  • Specific requirements for testing a machine or equipment to determine and verify the effectiveness of energy control measures.
  • Specific documentation steps if any. For example, each authorized person may be required to sign a lockout log indicating which lock is his, and the date or time installed.
  • Specific requirements for removing locks from a lockbox or hasp and from isolation devices so equipment can be returned to service.

Note: Exceptions to Energy Control Procedures, Minor Tool Changes, and Exclusive Control are referenced in mandatory Appendix D.

Lockout/Tagout Devices

The locks, tags, and other hardware that are identified and required will be the only devices used for lockout/tagout for personnel protection. The locks and tags used for personnel protection will be:

  • Standardized according to one or more of the following: color, shape, size, and in the case of tagout devices, print and format.
  • Lockout devices and tagout devices shall indicate the identity of the employee applying the device(s).
  • Locks shall be singularly keyed. Each lock shall have only one key. However locks can be keyed so that one key can open multiple locks.
  • Locks used for lockout/tagout shall not be used for any other purpose.

Specific requirements can be found in mandatory Appendix E Lockout/Tagout Devices

8.0 Certified Periodic Inspections

Periodic inspections of the energy control procedure shall be conducted at least annually to ensure that the procedure and the requirements are being followed. See Appendix F Periodic Inspections for specific requirements.

9.0 Training

Each department shall provide training so Authorized Employees, Affected Employees, and Others understand the purpose, and function of the program (knowledge, skills, application, use, removal, and start-up requirements).

Training and retraining shall be provided as described in mandatory
Appendix G Training for specific requirements.