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MFD Safety Program


Lock and Tag

LOTO Implementation Questions and Answers

Lock and Tag Program Manual

List of MFD Employee, their key numbers

What is the purpose of LOTO?

The purpose of LOTO is to prevent injury to servicing and /or maintenance employees due to the unexpected energization or startup of machines, equipment or processes; or the release of stored energy.

What energy sources are covered by LOTO?

Some people mistakenly think that LOTO applies only to electrical energy, when in fact LOTO applies to any potentially hazardous energy. Examples include:
  • Electrical
  • Mechanical
  • Hydraulic
  • Pneumatic
  • Stored energy such as that in batteries, capacitors, springs, flywheels
  • Thermal (hot surfaces, steam, extreme cold)
  • Chemical
  • Other

What activities are covered by LOTO?

Constructing, installing, setting up, adjusting, inspecting, modifying, maintaining and or servicing machines or equipment including, lubrication, cleaning or un-jamming of machines or equipment and making adjustments or tool changes, where employees would be exposed to the unexpected energization or startup of the equipment or release of hazardous energy.

If unexpected energization or startup of the equipment could hurt you, control it!

Lock and Tag Procedures

All machines, equipment, or circuits must be locked out following pre-established procedures. Lock out procedures fall into two categories.

  • Equipment Specific Lock and Tag Procedure (ELP) - this is a procedure written by the equipment owner for a specific machine, equipment or circuit. (note: do not confuse ELP with EWP, which stands for Electrical Work Plan.
    • MFD has a template to help equipment custodians prepare ELPs for their equipment.
    • Examples of completed ELPs can be found on the in the MFD Document Archive
  • General Lock and Tag Procedure (GLP) - this is a generic procedure provided in the LOTO manual, that can be used in place of an ELP provided all nine of the requirements in Section 4.4 of the LOTO Manual are met.

The equipment custodian is responsible for evaluating their equipment and preparing written Equipment Lockout Procedure, if required.

Authorized Employee

An authorized employee is a person who locks and tags machines or equipment in order to perform servicing or maintenance on that machine or equipment. Personnel become authorized employees by successfully completing Courses 136 and 157. Periodic retraining is required.

To apply LOTO, the authorized employee must:

  • be qualified - have the training, knowledge, and skill to de-energize and lock out the equipment; and,
  • have been approved by the department, group or shop responsible for the particular equipment as someone approved to lock out the equipment.

Requirements to apply LOTO:

  • Be current in training.  To check your training status, click here.
  • Be authorized to apply LOTO on ATA.
  • Have successfully completed a Course 157PRA within the past 12 months
  • Be knowledgeable and qualified to de-energize the equipment and to perform the specific lock out activities required.
  • Obtain permission from the equipment custodian before locking out the equipment (and be formally approved to used the ELP, if applicable).

Obtaining Locks and Tags

Working on Equipment that you are not authorized to lock out

If you need to work on equipment that you are not authorized to lock out:

  • Have an authorized person lock out the equipment using a multi-lock hasp or group lock box on each isolation point.
  • Apply your lock or locks on the each isolation point.
  • Witness verification of de-energization.

Before you touch any electrical components, you must verify zero voltage using testing instruments.  This verification process is considered "energized electrical work" and requires an approved electrical work-plan (EWP).


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