4.12 – Control of Hazardous Energy



To establish minimum guidelines for the control of hazardous energy, employee training requirements, and periodic inspections. This ensures that employees performing service or maintenance on equipment or machinery are knowledgeable of the hazards of stored energy. Refer to WorkSafeBC for additional requirements


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.  An employee who is working on or adjacent to potentially energized equipment, piping, or utilities where the separation is by a disconnect switch, a blind or a bulkhead.

AUTHORIZED EMPLOYEE – A person who locks out or tags out machines or equipment to perform service or maintenance on that machine or equipment. A person who provides isolation from a potential energy source. An affected employee becomes an authorized employee when that employee’s duties include installation, servicing or maintenance covered in these guidelines.

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 blockout or lockout can be achieved without the need to dismantle, rebuild, or replace the energy isolating device or permanently altering its energy control capability.

ENERGIZED – Connected to an energy source (electrical, mechanical, chemical, thermal, pressure) or containing residual or stored energy.

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 circuit breaker; a disconnect switch; a manually operated switch by which the conductors of the circuit can be disconnected from all ungrounded 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 devices are not energy isolating devices.

ENERGY SOURCE – Any source of electrical, hydraulic, pneumatic, chemical, thermal, or other energy.

HOT TAP – A procedure used in the repair, maintenance and services activities that involves welding on a piece of equipment (pipelines, vessel or tanks) under pressure, in order to install connection or appurtenances. It is commonly used to replace or add sections of pipeline without the interruption of service for air, gas, water, steam or petrochemical distribution systems.

LOCKOUT – 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 uses a positive means such as a lock, either a key or combination type, to hold an energy isolating device in a safe position and prevent the energizing of the machine or equipment. Also included are blank flanges and slip blinds.

NOTE: Lockout devices shall be standardized within the facility in at least one of the following criteria: color, shape, or size.

NORMAL PRODUCTION OPERATIONS – The utilization of a machine or equipment to perform its normal operation.

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 endangered by the unexpected energization or start up of equipment or release of hazardous energy.

SETTING UP – Any work performed to prepare a machine or equipment to perform its normal production operation.

TAGOUT – The placement of a warning or information tag on an energy isolating device, in accordance with an established procedure, to indicate the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.

NOTE: Tagout devices shall be standardized in print and format, their attachment devices shall be a non-reusable type, attached by hand, self locking, with a minimum unlocking strength of no less than 50 pounds (50 pounds (avoir) = 22.6796 kilograms); 50 pounds (troy) = 18.6621 kilograms) and having the general design and basic characteristics of being at least equivalent to a one piece all environment tolerant nylon cable tie.

TAGOUT DEVICE – A prominent warning device, such as a tag and a means of attachment, which can be easily fastened to an energy isolating device in accordance with an established procedure, to indicate that the energy isolation device and the equipment being controlled may not be operated until the tagout device is removed.

  1. Lockout devices shall be used, unless the usage of a lockout device would result in the need to dismantle, rebuild, replace the energy isolating device, or permanently alter its energy control capability.
  2. When a tagout device is used on any energy isolating device that is capable of being locked out the tagout device shall be attached at the same location that the lockout would have been.
  3. It shall be demonstrated that the tagout program, used in conjunction with another means of isolation will obtain the level of safety equivalent to that obtained by using the lockout.
    • a) In demonstrating that the level of safety is equivalent to that of the lockout program, all provisions of the tagout guidelines shall be followed.
    • b) Additional means to consider as part of the demonstration of full employee protection shall include the implementation of additional safety measures such as the removal of an isolating circuit element, blocking of a controlling switch, opening of an extra disconnecting device, or the removal of a valve handle to reduce the likely hood of inadvertent energization.

NOTE: Lockout/tagout devices shall be singularly identified and shall be the only device(s) used for controlling energy and shall not be used for other purposes.

  1. Affected employees shall be notified by supervision or the authorized employee of lockout/tagout applications or removal. The notification shall be given before the controls are applied and after they are removed from the machine or equipment.
  2. Before an authorized or affected employee turns off a machine, or a piece of equipment the authorized employee shall have knowledge of the type and magnitude of the energy, the hazards of the energy to be controlled, and the method or means to control the energy.  The machine or equipment shall be turned off, disconnected, and/or released (verify zero energy after the lockout is in place) using procedures established for that specific job. An orderly shutdown must be utilized before maintenance is performed so as to avoid hazards to employees.
  3. All energy isolating devices that are needed to control the energy to the machine or equipment before maintenance is performed shall be physically located and operated in such a manner as to isolate the energy source(s).  Lockout and or tagout devices shall be affixed to energy isolating devices by an authorized employee and when used, affixed in such a manner that it will hold the device in a safe or off position.  Workers are required to place their own lock on the lockout board or lock device at the start of their shift and then remove lock when the shift is complete.  Locks can be left on the lockout board or lock device longer than the designated shift if approved by Owner/Client.
  4. Following the application of the isolation device(s), all potentially hazardous stored or residual energy shall be relieved, disconnected, restrained, or otherwise rendered safe.  If re-accumulation is possible, verification of the safe isolation shall continue until the job is complete or the possibility no longer exists. Prior to start of the job, the authorized employee shall verify that the isolation has been accomplished.

When service and/or maintenance is performed by a crew, craft, department, or other group, a documented procedure shall be used to afford employees the level of protection equivalent to that provided by personal lockout/tagout procedure. Group lockout/tagout devices shall be used in accordance with the guidelines set forth in the General and Application requirements, including, but not limited to, the following specific requirements:

  • a) Primary responsibility is vested in one authorized employee for a set number of employees working under the protection of the group lockout/tagout procedure.
  • b) Provisions for the authorized employee to ascertain the exposure status of individual group members (e.g. permit must be in place showing accountability of lockout/placement of lock(s))
  • c) Where more than one crew, craft, department, etc. is involved, the assignment of the lockout/ tagout coordination to one authorized employee.
  • d) Each authorized employee shall affix a personal lockout/tagout device to the group lockout/ tagout device, group lock box, or comparable mechanism at the beginning of the job and remove at the end of the job.
  1. Before lockout and/or tagout devices are removed and the energy is restored, the authorized employee performs the following:
    • a) Inspect the work area to assure that tools and equipment have been removed.
    • b) Ensure that the machine or equipment components are operationally intact
    • c) Ensure that all employees are safely positioned or removed from the area.
    • d) Notify affected employees that the isolation devices have been removed.
  2. Lockout and or tagout devices shall be removed from each isolating device only by the authorized employee who applied them.

Exception: When the authorized employee who installed the device(s) is unavailable to remove it, the device may be removed under the supervision of the supervisor in charge of the job, provided:

  • a) Specific procedures and training for such removal have been developed, documented and entered as an appendix to the lockout/tagout guidelines.
  • b) The specific procedures shall include:
    • i. Verifying that the authorized employee is not on the job site.
    • ii. Making reasonable efforts to contact the authorized employee to inform him/her the isolating device(s) will be removed.
    • iii. Ensuring that the authorized employee is informed of the changes before he/she resumes work.



In situations where the lockout/tagout devices have to be temporarily removed for the purpose of testing or positioning the machine, equipment, and components thereof, any maintenance to be performed while the equipment is in operation the following sequence shall be followed:

  1. Hazard Assessment to be performed and documented that work on energized equipment will be performed
  2. Clear the machine or equipment of tools and/or material.
  3. Remove employees from the machine or equipment area that will not be working on the energized equipment.
  4. Remove locks from the lockout board or lock points in order to commission equipment to be tested or worked on.
  5. Energize and complete the testing or positioning or maintenance as to detailed procedure
  6. De-energize all systems and repeat isolation procedures.

Specific procedures shall be used during shift or personnel changes to ensure the orderly transfer of lockout/tagout devices and the continuity of protection of the oncoming and off going employees.

  1. A periodic inspection of the lockout/tagout program will be conducted at least annually. The inspection is conducted to ensure the procedure and requirements are being followed.  The inspection shall be performed by an authorized employee other than the authorized employee over the lockout/tagout being inspected. Any deviations and or inadequacies identified will be corrected.
  2. Where lockout procedures are being used, an interview is conducted with the authorized employee of his/her responsibilities under the program.  Where tagout procedures are being used, interviews with all authorized and affected employees are conducted of each employee’s responsibility under the program and the elements of training received.
  3. The completion of the periodic inspection must be certified.  The certification shall include the following:
    • a) Date of the inspection.
    • b) Identification of the machine or equipment inspected.
    • c) The employees included in the inspection, and
    • d) The authorized employee conducting the inspection.

Training shall be provided to ensure the purpose and function of the lockout/tagout guidelines are understood and the key knowledge and skills required for safe application, usage, and removal of the isolation devices are acquired by employees.  The training shall include the following:

  1. Authorized Employees
    • a) Recognition of applicable hazardous energy sources.
    • b) Type and magnitude of hazardous energy sources in the work place.
    • c) Methods and means necessary for energy isolation and control.
  2. Affected Employees
    • a) Instruction in the purpose and use of the lockout/tagout program
  3. All other employees whose work operations are or may be in the area where energy control procedures may be used.
    • a) Lockout/tagout guidelines.
    • b) Prohibiting the attempts of re-energization of isolated equipment.
    • c) Limitations of tagout devices.
    • d) Prohibiting removal of tagout devices.
  4. When tagout devices are used, employees shall be trained as follows:
    • a) Tags are essential warning devices and do not provide the physical restraint of locks.
    • b) Tags are not to be removed except by the authorized employee.
    • c) Tags must be legible and understandable by all employees.
    • d) Tags and their means of attachment must withstand the environment it’s used in.
    • e) Tags may evoke a false sense of security.
    • f) Tags must be attached to prevent inadvertent or accidental displacement.
    • g) Tags must be used in conjunction with another means of positive isolation.

Retraining shall be provided for all authorized and affected employees whenever:

  1. There is a change in their job assignment.
  2. A change in machines, equipment, or process that presents a new or different hazard.
  3. When the lockout/tagout procedures change.
  4. Whenever the periodic inspection reveals, or when employees believe, there are deviations in the program.

NOTE: The use of a client’s Lockout/Tagout (Control of Hazardous Energy) procedure may be used if it meets the minimum requirements set forth in OH&S Code, Part 10.

  1. A group lockout/tagout box may be used when maintenance or servicing is performed by a craft, crew, department, or other group that requires a number of isolation devices.
  2. The primary responsible authorized employee may place his/her isolation devices on the energy sources required to de-energize the machine or equipment. Upon completion of the de-energizing and lockout/tagout the primary authorized employee will place his/her keys in the group lock box and complete the Lockout Permit. Each authorized employee to perform servicing or maintenance on the isolated machine or equipment will then place his/her personal lockout/tagout device on the group lock box and then sign and date lockout sheet.
  3. Upon completion of the work to be performed or as each authorized employee completes their assigned work they will remove the personal lockout/tagout device from the group lock box. When all locks are removed from the box the primary responsible authorized employee who isolated the machine or equipment will then remove the keys from the box and proceed to remove each isolation device.
  4. If the job is not completed at the end of the work shift and the lock box is being used, one of the following shall be performed:
    • a) All authorized employees (except the primary responsible authorized employee) will remove their personal lockout/tagout devices from the group lock box.
    • b) Upon resuming the work on the next shift, the authorized employee will verify that his/her lockout/tagout devices have not been disturbed.
    • c) Then the authorized employees performing the work will replace their lockout/tagout devices on the group lock box, or
    • d)
  5. The group lock box will remain intact with all authorized employee’s personal locks and tags affixed to the group lock box.

NOTE: The isolation points shall be verified by the primary authorized employee before resuming work on the following shift.


If the group lockout/tagout is being used and another shift or different personnel are to continue work, the following procedure will be used:

  1. The primary authorized employee will coordinate with the oncoming primary authorized employee as to the status of the job, verify all isolation device locations and remove his lockout/tagout device from the lock box.
  2. The oncoming primary authorized employee will then place his lockout/tagout device on the lock box.
  3. Then, the oncoming authorized employees will place their personal lockout/tagout devices on the lock box.