Lock Out Tag Out: Safety Topics - June 2021 - Week 3



When thinking of energy, the first thing that comes to mind is electrical. But energy can come in many forms:

  • electrical
  • mechanical
  • hydraulic
  • pneumatic
  • chemical
  • thermal
  • and other sources in machines and equipment

During the servicing and maintenance of machines and equipment, unexpected start up and release of stored energy can occur and may result in injury or even death. Types of injuries that can occur are:

  • electrocution
  • burns
  • crushing
  • cutting
  • laceration
  • amputation
  • fracture of body parts

If equipment is not properly shut down before maintenance, injuries such as the following can occur:

  • a jammed conveyor belt that suddenly releases can crush the worker releasing the jam
  • a steam valve in a working area may release unexpectedly and burn nearby workers
  • or wiring on equipment may short if the electrical current has not been disconnected and shock the worker.

This is why following Lock Out Tag Out (LOTO) procedures is so important even for minor machine or equipment maintenance.


According to the OHSA website, “Failure to control hazardous energy accounts for nearly 10% of the serious accidents in many industries.” Having proper Lock Out Tag Out (LOTO) procedures and practices in place makes it easier to protect workers from hazardous energy release.

  1. Make sure workers are trained properly before trying to repair any type of equipment.
  2. If unsure of the process, workers must ask a supervisor or a senior worker how to safely repair the machine.
  3. The rule, as always, is: “If you do something new, make sure to review.”
  4. If you have been trained in the LOTO procedure but have not used it in a while, review it again.
  5. Follow the steps of correctly locking out the equipment and removing the energy sources.
  6. Do a hazard assessment – stop and think “What could happen? How would this happen? Who could be affected by this? Can it be done a better way? And what do I need to do to protect myself and others?”
  7. Once the equipment has been removed from all energy sources, think about the steps needed to complete the task. Do you have the correct tools? Are you trained or qualified to do the maintenance?
  8. If this is a complex task and the repair has any alterations that must done to the equipment, always review the machine’s manual and confirm maintenance is done correctly. Any alterations or incorrect use of the machine may cause other potential hazards.


Workers must be competent (adequately qualified, suitably trained, and with sufficient experience) to safely perform work without supervision or with a minimal degree of supervision. A worker is not to perform work on equipment slated to be serviced, repaired, or adjusted until the equipment is tested to guarantee that it is operative to avoid possible injury or harm.

The lock used must have a unique mark or identification tag on it that identifies the worker to whom the lock is assigned. The name of the worker to whom the lock or the identification tag is assigned must be readily available during the time the equipment is locked out.

An employer may use a group procedure if a large number of workers are working on machinery, equipment, or powered mobile equipment or a number of energy-isolating devices must be secured.

If a piece of equipment is to be serviced or repaired, it must be locked out. It will be locked out either at the machine or the circuit breaker panel.

Until the equipment has been returned to service, no employees should:

  • remove the lock out tag
  • remove the locking mechanism, or
  • attempt to operate the equipment.

A lock must not be removed from locked out equipment unless:

  • it is removed by the worker who installed it
  • the worker removing the lock ensures that no workers will be in danger if the lock is removed.

In an emergency or if the person who installed the lock is not available, the employer may delegate a competent and qualified employee to remove the tag locking device.


https://www.padlockoutlet.com/13852-thickbox_default/491b-master-lock-circuit-breaker-lockout.jpg             See the source image        See the source image

Circuit Breaker Lock                       Switch Panel Lock                    Lock out tag

Either or both locks above may be present. The lock out tag will be identified with the name of the person locking out the equipment.

Operating the Equipment

If machinery, equipment, or powered mobile equipment is to be serviced, repaired, tested or adjusted, no worker should perform work on the machinery, equipment, or powered mobile equipment until it has come to a complete stop.

A worker must lock out or lock and tag the equipment being serviced with the warning tag. Hazards associated with equipment are to be removed or controlled and rendered safe.

The equipment is to be rendered inoperative in a manner that prevents its accidental reactivation and provides equal or greater protection than the protection afforded by Lock Out Tag Out.

A hazard assessment will be completed to identify additional procedures and controls that must be in place if the manufacturer’s specifications require the machinery, equipment, or powered mobile equipment to remain operative while it is being serviced, repaired, tested, adjusted, or inspected or there are no manufacturer specifications and it is not reasonable to stop or render the machinery, equipment, or powered mobile equipment inoperative.

Securing devices are not to be removed until:

  • each involved worker is accounted for
  • any personal locks placed by workers are removed
  • procedures are implemented to verify that no worker is in danger before a worker removes the securing devices, and
  • the machinery, equipment, powered mobile equipment, piping, pipeline, or process systems is returned to operation.


Have you ever been in a situation when working on an item that needed repair and was thought to be disengaged suddenly becomes engaged? What hazards occurred and what could have been done to prevent it? What advice would you give someone before starting the task of repair?


Tags: safety topic , Lockout , Tagout , Lock , Out , Tag ,

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