Lockout of Electrical Installations or Machinery

UNB Reference Number: 7810
Authorized by: J. M. Anderson, President,
Effective Date: December 1, 1978
Revised: September 2001
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To outline procedures for lockout of electrical installations and machinery.


All University personnel working on electrical installations or machinery.


  1. Electrical Installations
    • Power supply to live electrical installations or related equipment shall be disconnected, locked out and tagged by a qualified electrician prior to commencement of repairs, maintenance, inspection or cleaning any piece of machinery or equipment.
    • Each electrician shall carry the following:
      • padlock and key
      • lockout tag which shall be signed and attached to the padlock at all times when lockout is required
      • lockout bar which will allow for the installation of more than one padlock if required, e.g., where other trades or contractors required to work on equipment.
    • After lockout of the equipment the key must be retained by the person to whom the padlock has been assigned.
    • In all cases where major or complex switching is entailed, the Physical Plant Department will provide written instructions. Supervision for the switching will be provided by the Physical Plant Department.
    • In the extreme case where it is not practicable to disconnect the electrical supply to an installation, the following steps must be taken:
      • a written work procedure shall be issued by the Physical Plant Department
      • rubber gloves, mats, shields, or other protective equipment adequate to ensure the safety of all persons shall be used.
      • no person shall be allowed to work alone.
      • all persons involved in such work shall be instructed on how to obtain emergency assistance from the Security Office.
  2. Machinery
    • The operator or person responsible for the machine shall put the machine in zero energy state i.e., shut off dry power, close valves, open bleeds, blank lines, etc.
    • Where applicable, the person responsible for the machine shall open the main electrical disconnect switch and install the padlock and lockout tag on the open switch.
    • Where more than one person or trade group is scheduled to work on the equipment a lockout bar will be used, this to allow for the use of more than one padlock.
    • The padlock placed by the operator or person responsible for the machine shall remain in place until all other padlocks have been removed and notification received that all work has been completed.

Special Note: A tag attached to locked out switches shall only be removed by the person who attached it; and upon completion of the inspection or repairs.

Refer further to the N.B. Occupational Health & Safety Act & Regulations