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Electrical Safety - Lock Out / Tag Out


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This procedure establishes the minimum requirements for the lockout or tagout of energy isolating devices. It will ensure that machines or equipment are isolated from all potentially hazardous energy, and locked out or tagged out before employees perform any servicing or maintenance. This is done to prevent unexpected energization, start-up or release of stored energy that will cause an injury.


The lockout/tagout requirements cover servicing and maintenance of machines and equipment for unexpected energization or start-up of machines or equipment, or the release of stored energy that would cause injury to employees. It does not cover:

    a. Construction, agriculture and maritime equipment
    b. Electric utilities
    c. Electrical exposure covered by Sub-art S
    d. Oil and gas well drilling and servicing
    e. Work on cord and plug connected equipment that is unplugged and under control of employee, and
    f. Gas steam, water or petroleum hot tap operations under certain circumstances.
Lockout is the preferred method of isolating machines or equipment from energy sources. All equipment shall be locked out or tagged out to protect against accidental or inadvertent operation when such operation could cause injury to personnel. Do not attempt to operate any switch, valve, or other energy isolating device when it is locked or tagged out.

Use a tagout system only if an isolating device cannot be locked out or there is demonstration that a tagout system provides full employee protection.


Each Department shall be responsible for the implementation of the lockout/tagout procedures. Employees shall have training in understanding the significance of implementing the procedures. Employees will use the lockout/tagout procedures when working on or near de-energized circuit parts or on equipment where there is a danger of injury because of unexpected energization of the circuit parts or unexpected start-up of the equipment.

The department shall provide training so employees understand the purpose, and function of the program (knowledge, skills, application, use, removal)

Training shall include:

    1. Recognition of hazardous energy sources, types and magnitude of energy available, the methods and means for isolation and control

    2. Purpose and use of the procedure

    3. Other employees whose work is in or may be in an area using lockout/tagout, and

    4. Instruction about procedure, and prohibition concerning starting locked or tagged equipment.
When using tagout systems, training will include the following limitations of tags:
    1. Tags are essentially warning devices and do not provide physical restraint
    2. Do not remove tags without permission of the authorized person using it
    3. Tags must be legible and understandable to be effective
    4. Tags and their means of attachment must withstand the environment
    5. Tags may evoke a false sense of security and must be understood as part of an overall program, and
    6. Tags must be securely attached.

Employee Retraining

    1. There shall be retraining with any change in job assignments, or change in machines, equipment, or process that presents a new hazard, or a change in energy control procedures.

    2. Retrain when inspection reveals a need, or whenever the employer sees a need.

    3. Retraining shall reestablish proficiency and introduce new or revised control methods.

Coordination With Other Procedures

Implement electrical lockout/tagout procedures in coordination with appropriate procedures for safely isolating other energy systems. Some examples are hydraulic, pneumatic, thermal, process gases and fluids, chemical, and mechanical. This procedure will provide for the isolation of all energy sources that could endanger employees.

Lockout/Tagout Device Requirements

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

    1. Standardized according to one or more of the following: color, shape, size, type, or format
    2. Distinctive in appearance, easily recognizable, clearly visible
    3. Designed to convey all information required for the application
    4. Designed to deter accidental or unauthorized removal
    5. Designed to withstand environmental conditions for the duration of their application
The employer will provide the locks, tags, chains, wedges, key blocks, adaptor pins, self-locking fasteners, or other hardware. Lockout/tagout devices are to be singularly identified; and the only devices used for controlling energy. Do not be use these f or other purposes. They must be:


    1. Capable of withstanding environmental conditions for the maximum period of use
    2. Constructed and printed so exposure will not cause deterioration of the message on the tag, and
    3. Tags shall not deteriorate when used in a corrosive environment.

    1. Must prevent removal without excessive force or unusual techniques such as bolt cutter or cutting tools
    2. Must be substantial enough to prevent inadvertent or accidental removal
      a. Non-reusable type
      b. Attachable by hand
      c. Self-locking
      d. Non-releasing with a minimum unlocking strength of less than 50 pounds, and
      e. Similar to the general design and basic characteristics of being at least equivalent to a one-piece, all environment-tolerant nylon cable tie.

    1. Lockout/tagout devices must have the identity of the employee and tagout devices must warn against hazardous conditions.

    Messages must include:


Procedural Requirements

The department shall document the lockout/tagout procedure. It shall contain the requirements to safeguard employees while they are working on or near de-energized circuits, parts or equipment. Procedures shall require preplanning to determine where and how employees will disconnect electric energy sources to safely de-energize circuits and equipment.

Preparation for Lockout or Tagout

The program will have equipment shutdown procedures so the electric equipment involved is safely shut down before circuits are de-energized.

Appropriate employees shall be instructed in the safety significance of the lockout/tagout procedure. Each affected new or transferred employee and other employees whose work operations are or may be in the area, shall have instruction in the purpose and use of the lockout or tagout procedure.


Inspect carefully and locate and identify all isolating devices. Be certain which switch(s), valve(s), or other energy isolating devices control the equipment to be locked or tagged out. More than one energy source (electrical, mechanical, or others) may be involved. All types and locations(s) of energy isolating means must be found and managed.

Sequence of Lockout or Tagout System Procedures

1. Notify all affected employees that a lockout or tagout system is going to be used. The authorized employee shall know the type and magnitude of energy that the machine or equipment uses and shall understand its hazards

2. If the machine or equipment is operating, shut it down by the normal stopping procedure (depress stop button, open toggle switch, etc.).

3. Operate the switch, valve, or other energy isolating device(s) to isolate the equipment from its energy source(s). Dissipate, deactivate or restrain stored energy (such as that in 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.

4. Lockout or tagout the energy isolating devices with assigned individual lock(s) or tag(s). Use the method(s) selected; i.e., locks, tags and additional safety measure, etc.

5. This ensures personnel protection, and acts as a check on the disconnection of the energy sources. Operate the push button or other normal operating controls to make certain the equipment will not operate.

Caution: Return operating control(s) to "neutral" or "off" position after the test.

6. The equipment is now locked out or tagged out.

Restoring Machines or Equipment to Normal Production Operations

1. After completing the service or maintenance and determining that the equipment is ready for normal production operations, check the area around the machines or equipment to ensure that everyone is clear.


2. After removing all tools from the machine and reinstalling equipment guards and determining that all employees are in the clear, remove all lockout or tagout devices. Operate the energy isolating devices to restore energy to the machine or equipment.

Procedure Involving More Than One Person

In the preceding steps, if more than one individual is required to lockout or tagout equipment, each shall place their own personal lockout device or tagout device on the energy isolating device(s). When an energy isolating device cannot accept multiple locks or tags, use a multiple lockout or tagout device (hasp). If using lockout, use a single lock to lockout the machine or equipment. Place the key in a lockout box or cabinet that allows the use of multiple locks to secure it. Each employee will then use their own lock to secure the box or cabinet. As each person no longer needs to maintain their lockout protection, that person will remove their lock from the box or cabinet.

Group Lockout and Tagout

Group lockout/tagout refers to a leader locking/tagging out for workers under his immediate control on the same work crew. The following persons are authorized to perform group lockout/tagout:

Periodic Inspection

Inspect energy control procedure at least annually. The inspection must be:

    1. Performed by an authorized employee (other than those being inspected)
    2. Designed to correct any deviations or inadequacies observed
    3. Reviewed with employees locking out equipment as well as their responsibilities for lockout
    4. Reviewed with employees tagging out equipment as well as their responsibilities
    5. Inspection reports will be kept in the departmental file for 30 years
    6. Identify machine, show date of inspection, list employees included, and identify person performing the inspection.

Outside Personnel

Any outside contractor or non-agency personnel will receive information about lockout/tagout policies affecting their procedures from the department hiring the contractor.