De-energization and Lockout

[OHS Regs., s.xx] Follow these links to related legislation.

Highlighted words reveal definitions when selected.

Every year, workers are killed or seriously injured due to exposure to a hazardous energy source, such as an unexpected release of energy or the unintended start of machinery or equipment. To prevent such tragedies, it is critical that workers de-energize and lockout hazardous energy sources following appropriate procedures.

Employer Responsibilities

Employers must make sure:

  • An energy source is isolated and controlled where it is possible that unexpected energization or start up of machinery or equipment could cause injury to workers. [OHS Regs., s. 128]
  • Work on machinery or equipment that is shut down for maintenance does not start until: [OHS Regs., s. 129(1)] [OHS Regs., s. 484(1)]
    • All parts and attachments that may move are secured;
    • All energy sources that could result in worker exposure are effectively controlled; and
    • All applicable energy isolating devices have been locked out.
  • Workers follow the procedures for shutting down equipment and machinery for maintenance, and where a normal production activity includes a risk of injury from movement or energy that is not effectively safeguarded. [OHS Regs., s. 129 (2)]
  • Where lockout is required: [OHS Regs., s. 130] [OHS Regs., s. 131]
    • Written lockout procedures are developed, made available to applicable workers, and workers are proficient in using them;
    • Locks are used to secure energy isolating devices in a safe position and following the lockout procedure;
    • Workers have enough personal locks to complete the lockout;
    • No combination locks are used;
    • Personal locks are marked, labelled or tagged to identify the person applying it, the equipment being locked out, and the date the lock was applied;
    • Procedures are followed for the transfer of the lockout between personnel changes, if applicable;
    • If personal lock(s) are not practical, use another effective method approved by OHS division;
    • Locks do not obstruct access to other energy isolating devices that could pose a hazard to workers;
    • An effective means of verifying the lockout is completed before work begins; and
    • A worker verifies that all energy sources have been effectively locked out before work begins.

High voltage equipment [OHS Regs., s. 490] [OHS Regs., s. 492]

Employers must make sure: [OHS Regs., s. 490(1) and (2)]

  • High voltage electrical equipment is completely isolated, grounded and locked out before work begins, if practical. Where it is not practicable, conduct a formal hazard assessment and develop an electrical safety program that includes:
    • Written safe work procedures;
    • The number of qualified persons required to be present while the work is being done; and
    • Appropriate electrical protective equipment, including rubber blankets, hoses, hoods, gloves and live line tool. This equipment must be selected, used, stored, tested and maintained in accordance with a standard acceptable to OHS Division.
  • A worker does not work on an energized electrical conductor or equipment, unless procedures satisfactory to OHS Division are used and the worker is provided with and trained in the use of special tools. [OHS Regs., s. 490(3)]
  • Signs are posted stating "Danger, Energized Equipment" before energizing high voltage electrical equipment. These signs must be located close to the equipment and in an area visible to workers. [OHS Regs., s. 491]
  • A high voltage power system is de-energized before starting work. The worker in charge must make sure that the part of the system being worked on is isolated, grounded and locked out, if required. [OHS Regs., s. 492 (1)]
  • A barrier or other form of distinctive identification is used to differentiate high voltage electrical equipment which has been de-energized for safety reasons from similar energized equipment where a lack of identification would result in undue risk to workers. [OHS Regs., s. 492 (2)]
  • Where it is impracticable to lockout a power system or part of a power system, make sure to: [OHS Regs., s. 492 (3)]
    • Clearly define the boundaries of the power system or part;
    • Follow written work procedures respecting safety protections and comply with legislation; and
    • Uniquely identify the major equipment used to establish safety protection guarantees – in a highly visible location on or near the equipment.
  • Only one person is assigned be the “person in charge”, who has the sole authority to establish the conditions for the power system and issue safety protection guarantees.  This person must: [OHS Regs., s. 493]
    • Make sure the status of the power system or part of the system is accurately shown on a mimic display;
    • Maintain a log of switching details, safety protection guarantees, and operational events;
    • Authorize when work can begin on a power system or part of it; and
    • Maintain an effective communication between themselves and the workers doing the work.
  • Only a worker authorized by the owner may get a safety protection guarantee or do work on the power system or parts of it. [OHS Regs., s. 493(4)]
  • Written switching orders are prepared and followed when a switching sequence requires the operation of three or more devices. [OHS Regs., s. 494]
  • When working under a safety protection guarantee:
    • An isolating device that supplies the safety protection guarantee provides a visual verification of the opening of an isolation point.   [OHS Regs., s. 495(1)]
    • The isolating device is locked in a position or condition that will protect a worker before the work begins. [OHS Regs., s. 495(2)]
    • A distinctive “DO NOT OPERATE” tag is placed securely on the isolating device.  [OHS Regs., s. 495(3)]
  • Test equipment that will be worked on to verify it is isolated before grounding and blocking. [OHS Regs., s. 496(1)]
  • After testing but before work begins, the person at the worksite who is responsible for the crew must verify that the required grounding and blocking devices are in place. [OHS Regs., s. 496(2)]
  • Equipment must be grounded or blocked as closely as practical to the worksite when there is a hazard to the workers. [OHS Regs., s. 496(3)]
  • Grounding and blocking devices maybe removed to conduct tests after lockout procedures have been followed. [OHS Regs., s. 496(5)]
  • Follow safe work procedures acceptable to the OHS Division when grounding and blocking are not safe or practical. [OHS Regs., s. 496(4)]
  • When there are two or more power systems, or two or more persons in charge of different parts of the system, establish written procedures to be followed to make sure the safety protection guarantee is effective. [OHS Regs., s. 497]

Where group lockout is used, the employer must: [OHS Regs., s. 134]

  • Make sure written procedures are followed.
  • Make sure that two qualified workers:
    • Independently lockout the energy isolating devices;
    • Use a primary key securing system to secure the keys for the locks using their personal locks or a positive sealing devices acceptable to OHS Division; and
    • Complete, sign, and post a checklist that identifies the machinery or equipment covered in the lockout.
  • Make sure that workers apply their personal locks to the key securing system before beginning work.
  • Make sure that workers only lockout a secondary key securing system, where two qualified workers lockout the primary securing system and place their keys in the secondary securing system.
  • Make sure workers remove their personal locks from a key securing system only when their portion of work is complete and it is safe to do so.
  • Make sure that two qualified workers are responsible for ending a group lockout by removing their locks from a key securing system or positive sealing device from a key securing system, once all personal locks have been removed and when it is safe to do so.
  • Make sure that a written group lockout procedure is posted in a place that is visible when the system is in use.

Where lockout of an energy isolating device is not required or practical, the employer must: [OHS Regs., s. 135(1)]

  • Follow the OHS requirements that apply to power systems or mobile equipment, if applicable.
  • Make sure that machinery equipped with a control system isolating device(s) is locked out according to legislation.
  • Make sure that an energy isolating devices or control system isolating device(s) is effectively controlled to prevent unintended start-up or energy release during an emergency.

Where locks are not required or practical (as above): [OHS Regs., s. 136]

  • The energy isolating device must be under the exclusive and immediate control of the worker at all times while working on the machinery or equipment; or
  • The tool, machine, or equipment receives power through a readily disconnected supply, including an electrical cord or quick release air or hydraulic line, that is disconnected from its power supply and its connection point is kept under the immediate control of the worker at all times while the work is being done.

The use of control system isolating device(s) and associated procedures must be approved by OHS Division.  When approved, they must only be used by a qualified and authorized worker. [OHS Regs., s. 135]

When it is not practical to shut down machinery or equipment for maintenance, only parts essential to their operation may remain energized and only a qualified worker can do the maintenance following written safe work procedures. [OHS Regs., s. 137]

Supervisor Responsibilities (Removal of Locks)

When a worker is unable to remove their personal lock and a supervisor must remove it, the supervisor must: [OHS Regs., s. 133]

  • Make every effort to contact the worker who installed the lock;
  • Make sure the machinery or equipment is safe to operate before removing the lock;
  • Make sure locks that are not in use are removed from the machinery or equipment; and
  • Notify the worker that their lock has been removed at the start of their next shift.

Worker Responsibilities

Workers must:

  • Lockout energy isolating devices before starting work except where not required by the legislation. [OHS Regs., s. 132(a)]
  • Verify that all energy sources have been locked out before beginning work. [OHS Regs., s. 131(2)]
  • Remove personal locks when work is completed. [OHS Regs., s. 132(b)]
  • Keep immediate control of the lock key during the work. [OHS Regs., s. 132(c)]
  • Make sure locks are labelled to identify the person applying the lock, the equipment being locked out and the date the lock was applied. [OHS Regs., s. 130(4)]
  • Follow safe work practices and procedures, including lockout procedures.
  • Properly wear or use personal protective equipment, safeguards and safety devices provided for their protection in accordance with the manufacturer’s instructions and training provided by the employer. [OHS Act, s. 7(a)(a.1)] [OHS Regs., s. 17]
  • Participate in training and hazard assessments, where it is offered.
  • Not use equipment or perform work tasks where the required training has not yet taken place.
  • Immediately report concerns and hazards to the supervisor or employer. [OHS Regs., s. 17(3)]

Related topics

Energy source

An electrical, mechanical, hydraulic, pneumatic, chemical, thermal or other source of energy of potential harm to workers. [OHS Regs., s. 127]

Isolated

Normal sources of energy have been disconnected by opening and securing all associated switches, and that mechanical equipment has been rendered and secured non-operative by disconnecting, stopping, depressurizing, draining, venting or other effective means. [OHS Regs., s. 477(e)]

Maintenance

Work performed to keep machinery or equipment in a safe operating condition, including installation, repair, cleaning, lubrication and the clearing of obstructions. [OHS Regs., s. 127]

Normal production

Work that is routine, repetitive, and integral to the normal use of machinery or equipment for production. [OHS Regs., s. 127]

Energy isolating device

A device that physically prevents the transmission or release of an energy source to machinery or equipment. [OHS Regs., s. 127]

Personal lock

A lock provided by the employer for use by a worker to ensure personal lockout protection such that each lock, when applied, is operable only by a key in the worker’s possession, and by a key under the control of the supervisor or manager in charge. [OHS Regs., s. 127]

OHS Division

Occupational Health and Safety Division, of Digital Government and Service NL regulates occupational health and safety in all provincial workplaces in the province of Newfoundland and Labrador. To date there are approximately 20,000 employers employing about 220,000 workers in the province.

The Division is supported by a complement of staff including OHS officers, industrial hygienists, engineers and radiation specialists to perform various multi-disciplinary activities such as:

  • Investigating workplace accidents and statistics
  • Conducting compliance inspections and detailed audits of workplaces
  • Enforcing Occupational Health and Safety Legislation

https://www.gov.nl.ca/dgsnl/department/branches/divisions/ohs/

Group lockout

Where a large number of workers are working on a piece of equipment or machinery, or a large number energy isolating devices are to be locked out. [OHS Regs., s. 134(1)]

Key securing system

A system which physically prevents access to keys when locks or positive sealing devices are applied in a group lockout procedure. [OHS Regs., s. 127]

Power systems

A plant and equipment essential to the generation, transmission or distribution of electricity, including a plant or equipment that is out of service, being constructed or being installed. [OHS Regs., s. 477(g)]

Mobile equipment

A wheeled or tracked vehicle which is engine or motor powered, together with attached or towed equipment, but does not include a vehicle operated on fixed rails or tracks. [OHS Regs., s. 250]

Control system isolating device

A device that physically prevents activation of a system used for controlling the operation of machinery or equipment. [OHS Regs., s. 127]

Personal protective equipment (PPE)

Personal protective equipment (PPE) reduces the risk of exposure to a hazard through the use of protective clothing or devices. PPE is the least effective way to protect workers and should only be used when other controls are not practical or adequate.

OCCUPATIONAL HEALTH AND SAFETY ACT
R.S.N.L. 1990, c. O-3

Section 7 Specific duties of workers

7. A worker

(a) shall co-operate with his or her employer and with other workers in the workplace to protect

(i) his or her own health and safety,

(ii) the health and safety of other workers engaged in the work of the employer,

(iii) the health and safety of other workers or persons not engaged in the work of the employer but present at or near the workplace;

(a.1) shall use devices and equipment provided for his or her protection in accordance with the instructions for use and training provided with respect to the devices and equipment;

(b) shall consult and co-operate with the occupational health and safety committee, the worker health and safety representative or the workplace health and safety designate at the workplace; and

(c) shall co-operate with a person exercising a duty imposed by this Act or regulations.

[S.N.L. 1999, c. 28, s. 3; 2001, c. 10, s. 26; 2004, c. 52, s. 2]

Occupational Health and Safety Regulations, 2012
N.L.R. 5/12

Part III GENERAL DUTIES

Section 17 General duties of workers

17. (1) A worker shall make proper use of all necessary safeguards, protective clothing, safety devices, lifting devices or aids, and appliances

(a) designated and provided for the worker’s protection by the employer; or

(b) required under these regulations to be used or worn by a worker.

(2) A worker shall follow the safe work procedure in which the worker has been instructed.

(3) A worker shall immediately report a hazardous work condition that may come to the worker’s attention to the employer or supervisor.

[N.L.R. 43/22, s. 4]

Part IX DE-ENERGIZATION AND LOCKOUT

Section 127 Definitions

127. In this Part

(a) "control system isolating device" means a device that physically prevents activation of a system used for controlling the operation of machinery or equipment;

(b) "energy isolating device" means a device that physically prevents the transmission or release of an energy source to machinery or equipment;

(c) "energy source" means an electrical, mechanical, hydraulic, pneumatic, chemical, thermal or other source of energy of potential harm to workers;

(d) "key securing system" means a system which physically prevents access to keys when locks or positive sealing devices are applied in a group lockout procedure;

(e) "lockout" means the use of a lock to render machinery or equipment inoperable or to isolate an energy source in accordance with written procedure;

(f) "maintenance" means work performed to keep machinery or equipment in a safe operating condition, including installation, repair, cleaning, lubrication and the clearing of obstructions;

(g) "normal production" means work that is routine, repetitive, and integral to the normal use of machinery or equipment for production; and

(h) "personal lock" means a lock provided by the employer for use by a worker to ensure personal lockout protection such that each lock, when applied, is operable only by a key in the worker's possession, and by a key under the control of the supervisor or manager in charge.

Section 128 General requirement

128. Where the unexpected energization or startup of machinery or equipment or the unexpected release of an energy source could cause injury, the energy source shall be isolated and effectively controlled.

Section 129 When lockout required

129. (1) Where machinery or equipment is shut down for maintenance, no work may be done until

(a) all parts and attachments have been secured against inadvertent movement;

(b) where the work would expose workers to energy sources, the hazard has been effectively controlled; and

(c) the energy isolating devices have been locked out as required by this Part.

(2) Where machinery or equipment is in use for normal production work, subsection (1) applies where a work activity creates a risk of injury to workers from the movement of the machinery or equipment, or exposure to an energy source, and the machinery or equipment is not effectively safeguarded to protect the workers from the risk.

Section 130 Lockout procedures

130. (1) Where lockout of energy isolating devices is required, the devices shall be secured in the safe position using locks in accordance with procedures that are made available to all workers who are required to work on the machinery or equipment.

(2) An employer shall ensure that each worker required to lock out has ready access to sufficient personal locks to implement the required lockout procedure.

(3) Combination locks shall not be used for lockout.

(4) A personal lock shall be marked or tagged to identify the person applying it, the equipment being locked out and the date the lock was applied.

(5) Procedures shall be implemented for shift or personnel changes, including the orderly transfer of control of locked-out energy isolating devices between outgoing and incoming workers.

(6) Where the use of a personal lock is not practicable for lockout, other effective means approved by the minister may be used in place of a personal lock to secure an energy isolating device in the safe position.

(7) Where an energy isolating device is locked out, the lock shall not prevent access to other energy isolating devices supplying machinery or equipment that could cause injury to workers.

Section 131 Checking locked out equipment

131. (1) Effective means of verifying lockout shall be provided and used.

(2) Before commencing work, a worker shall verify that all energy sources have been effectively locked out.

Section 132 Worker responsibilities

132. A worker who works on machinery or equipment requiring lockout is responsible for

(a) locking out the energy isolating devices before starting work except as provided by section 134;

(b) removing personal locks on the completion of work; and

(c) maintaining immediate control of the key to personal locks throughout the duration of the work.

[N.L.R. 43/22, s. 20]

Section 133 Removal of locks

133. (1) A personal lock shall only be removed by the worker who installed it, or where this is not possible, the matter shall be referred to the supervisor who shall be responsible for its removal.

(2) A supervisor shall

(a) make every reasonable effort to contact the worker who installed the lock;

(b) ensure that the machinery or equipment can be operated safely before removing the lock; and

(c) ensure that locks that are not in active use are removed from machinery or equipment.

(3) A worker shall be notified at the start of the worker’s next shift where the worker's personal lock has been removed since the worker's previous shift.

[N.L.R. 43/22, s. 21]

Section 134 Group lockout procedure

134. (1) Where a large number of workers are working on machinery or equipment or a large number of energy isolating devices are to be locked out, a group lockout procedure that meets the requirements of this section may be used.

(2) In a group lockout procedure, 2 qualified workers shall be responsible for

(a) independently locking out the energy isolating devices;

(b) securing the keys for the locks used under paragraph (a) with personal locks or other positive sealing devices acceptable to the minister; and

(c) completing, signing and posting a checklist that identifies the machinery or equipment components covered by the lockout.

(3) Before commencing work, a worker working on the locked out components shall apply a personal lock to the key securing system referred to in paragraph (2)(b).

(4) Workers may lock out a secondary key securing system where 2 qualified workers lock out the primary key securing system and place their keys in the secondary system.

(5) On completion of work, a worker referred to in subsections (3) and (4) shall remove the worker's personal lock from the key securing system.

(6) Where the requirements of subsection (5) have been met and it has been determined that it is safe to end the group lockout, 2 qualified workers shall be responsible for removing their personal locks or the positive sealing device from the key securing system containing the locks referred to in paragraph (2)(a), and when those keys are released, the system is no longer considered to be locked out.

(7) The written group lockout procedure shall be conspicuously posted at the place where the system is in use.

[N.L.R. 43/22, s. 22]

Section 135 Alternative procedures

135. (1) Where lockout of energy isolating devices as required by section 129 is not practicable,

(a) in the case of a power system as defined in Part XXVI, the requirements of that Part shall be followed;

(b) in the case of mobile equipment as defined in Part XII, the requirements of that Part shall be followed;

(c) in the case of machinery equipment designed and equipped with effective control system isolating devices, the devices shall be locked out as required by sections 130 to 134 and subsection (2); and

(d) in an emergency, the energy isolating devices or control system devices shall be effectively controlled to prevent inadvertent start-up or hazardous energy release.

(2) Control system isolating devices and the procedures for their use shall be approved in writing by the minister and shall be used by a qualified worker authorized to carry out the work.

Section 136 Where locks not required

136. The application of a lock is not required under section 129 or 135 where

(a) the energy isolating device is under the exclusive and immediate control of the worker at all times while working on the machinery or equipment; or

(b) a tool, machine or piece of equipment that receives power through a readily disconnected supply, including an electrical cord or quick release air or hydraulic line, is disconnected from its power supply and its connection point is kept under the immediate control of the worker at all times while the work is being done.

Section 137 Work on energized equipment

137. Where it is not practicable to shut down machinery or equipment for maintenance, only the parts which are vital to the process may remain energized and the work shall be performed by a qualified worker who has been authorized by the employer to do the work and provided with and follows written safe work procedures.

Part XII POWERED MOBILE EQUIPMENT

Section 250 Definitions

250. In this Part

(a) "mobile equipment" means a wheeled or tracked vehicle which is engine or motor powered, together with attached or towed equipment, but does not include a vehicle operated on fixed rails or tracks;

(b) "no significant hazard of rollover" means an area in which there are no grades exceeding 10%, no operating areas with open edges, and no open ramps, loading docks, ditches or other similar hazards which may cause a rollover; and

(c) "specific location" means a yard, plant or other clearly defined and limited area in which mobile equipment is operated, but does not include a entire municipality, district, transient forestry operation or construction site.

Part XXVI ELECTRICAL OPERATIONS

Section 477 Definitions

477. In this Part

(a) "conductor" means a wire, cable or other metal component installed for the purpose of conveying electric current from one piece of equipment to another or to ground;

(b) "control system" means a manual, remote, automatic or partially automatic system for controlling the operation of equipment;

(c) "electrical equipment" includes machinery, a plant, works, wires, pipes, poles, conduits, apparatus, appliances and equipment, designed or used or intended for use for or in connection with the generation, transmission, supply, distribution or use of electrical energy for any purpose;

(d) "high voltage" means a potential difference (voltage) of more than 750 volts between conductors or between a conductor and ground;

(e) "isolated" means that normal sources of energy have been disconnected by opening and securing all associated switches, and that mechanical equipment has been rendered and secured non-operative by disconnecting, stopping, depressurizing, draining, venting or other effective means;

(f) "low voltage" means a potential difference (voltage) from 31 to 750 volts inclusive, between conductors or between a conductor and ground;

(g) "power system" means a plant and equipment essential to the generation, transmission or distribution of electricity, including a plant or equipment that is out of service, being constructed or being installed; and

(h) "safety protection guarantee" means an assurance that a power system or part of the power system is isolated and will remain isolated.

Section 484 Low voltage electrical equipment - disconnection and lockout

484. (1) Low voltage electrical equipment shall be completely disconnected and locked out where required by Part IX before work is started on it.

(2) Where it is not practicable to completely disconnect low voltage electrical equipment, work shall be performed in accordance with an electrical safety program in accordance with a standard acceptable to the minister that

(a) includes emergency procedures and emergency release of victims;

(b) requires the use of appropriate electrical protective equipment, including flame retardant clothing, voltage-related rubber gloves and cover up and other necessary live line tools;

(c) provides that, where practicable, uncontrolled liquid is not permitted close to a worker working on the equipment;

(d) prohibits the use of metal ladders, wooden ladders with wire reinforced side rails, metal scaffolds or metal work platforms; and

(e) has available up to date diagrams.

Section 490 Isolation and lockout

490. (1) High voltage electrical equipment shall, where practicable, be completely isolated, grounded and locked out where required by these regulations before work is started on it.

(2) Where it is not practicable to completely isolate high voltage electrical equipment an employer shall conduct a formal hazard assessment and develop an electrical safety program that includes

(a) written safe work procedures;

(b) the number of qualified persons required to be present while the work is being done; and

(c) providing appropriate electrical protective equipment, including rubber blankets, hoses, hoods, gloves and live line tools that shall be selected, used, stored, tested and maintained in accordance with a standard acceptable to the minister.

(3) A worker shall not work on an energized electrical conductor or equipment, unless procedures satisfactory to the minister are used and the worker is provided with and trained in the use of special tools, approved for use by an authority acceptable to the minister.

Section 491 Warning signs

491. Before completing installation and after energizing high voltage electrical equipment, conspicuous signs visible to a worker shall be placed close to the equipment stating "Danger, Energized Equipment".

Section 492 De-energized high voltage systems - isolation and lockout

492. (1) Before working on a high voltage power system that, for reasons of safety, shall be de-energized, the worker in charge shall ensure that the part of the system being worked on is isolated and grounded and locked out where required by these regulations.

(2) A barrier or other form of distinctive identification shall be used to differentiate high voltage electrical equipment which has been de-energized for safety reasons from similar energized equipment at the work location where a lack of identification would result in undue risk to workers.

(3) Where it is impracticable to lock out a power system or part of a power system,

(a) the boundaries of the power system or part shall be clearly defined;

(b) written work procedures respecting safety protection guarantees and complying with the requirements of sections 493 to 497 shall be followed; and

(c) major equipment used to establish safety protection guarantees shall be uniquely identified at a conspicuous place on or near the equipment.

Section 493 Person in charge

493. (1) Only one person at a time shall be assigned as the person in charge with the exclusive authority to establish the conditions for, and to issue safety protection guarantees for, the power system or part of it.

(2) The person in charge referred to in subsection (1) shall

(a) ensure that the status of the power system or assigned part of the power system is accurately represented on a mimic display;

(b) maintain a log of switching details, safety protection guarantees and operational events; and

(c) authorize the commencement of work on the power system or assigned part of it.

(3) There shall be an effective communication system between the person in charge and workers doing the work.

(4) Only a worker specifically authorized by an owner may receive a safety protection guarantee or do work on the power system or assigned part of the power system.

Section 494 Switching sequences

494. Where a switching sequence requires the operation of 3 or more devices, a written switching order shall be prepared and followed.

Section 495 Isolating devices

495. (1) An isolating device used to provide a safety protection guarantee shall provide for visual verification of the opening of an isolation point.

(2) A lockable isolating device shall be locked in the position or condition required to protect a worker before work commences under a safety protection guarantee.

(3) A distinctive "DO NOT OPERATE" tag shall be placed securely on an isolating device used for a safety protection guarantee.

Section 496 Grounding and blocking

496. (1) While a safety protection guarantee is in effect, the equipment to be worked on shall be tested to verify isolation before grounding and blocking begin.

(2) After the testing referred to in subsection (1) has been done, the person at the worksite responsible for a crew shall verify that the required grounding and blocking devices are in place before work begins.

(3) Grounding and blocking of equipment that may be hazardous to workers shall be carried out as closely as practicable to the worksite.

(4) Where grounding and blocking is not safe or practicable, written safe work procedures acceptable to the minister shall be followed.

(5) Grounding and blocking devices may be removed for the purpose of conducting tests after lockout procedures have been followed.

Section 497 Multiple authorities

497. Where a safety protection guarantee involves 2 or more power systems or 2 or more persons in charge of different parts of a system, appropriate written procedures shall be established and followed to ensure that the safety protection guarantee is effective.