LOTO Course page 3 | Industrial & Construction Safety Solutions





A statement that explains the company’s directives concerning tagging and locking out, it should cover:

When to Lock Out?

  • Any time you service or perform maintenance on any machinery or equipment that includes constructing, installing, setting up, adjusting, inspecting, repairing, or cleaning

Where to Lock Out?

  • Locks and tags are applied to all primary and secondary energy sources (Electrical, Hydraulic, Pneumatic, Mechanical, Kinetic, Chemical, Thermal)


A set of steps used to lock out specific machines, steps include:

  • A list and location of all energy sources
  • Other equipment in the area that must be locked out
  • Special hazards/circumstances
  • Sequential steps
  • Testing methods
  • Start up

Codes of Practice

Procedures that are outlined for working in certain situations where regulations do not fit. A Code of Practice must be written in great detail and posted at the worksite. Codes of Practice are accepted under the OHSA.

Group lockout falls into Code of Practice:

  • An identification
  • Identification of persons at risk
  • Identification of persons responsible
  • Time, day, or event, etc. before, during, or after which the code of practice may apply
  • The locations where the code of practice may apply
  • The methods and any equipment to be used to ensure the health and safety of any person at risk
  • Emergency procedures and equipment which might be required in the event of failure of any of  the regular procedures or equipment

Lock & Tag Procedure

Prepare for Shutdown

  • Do you know your machine? What kind of energy are we dealing with? More than 1 type? What are the hazards present and what are the controls necessary?

Shut down the equipment

  • Have you advised other workers? Do you know the normal stopping procedure? Off switch, pedals, controls? Other methods?

Isolate the equipment

  • Cut off every source of energy (valves, main disconnects, circuit breakers). Do not forget auxiliary power (electrical, secondary steam, hydraulic, pneumatic). Do not forget secondary sources of energy (backup generators).

Verify Isolation

  • After ensuring that no workers can be injured, operate the push button or other normal controls to verify that all energy sources have been disconnected and the equipment will not operate. 
  • If there is a possibility of re-accumulation of stored energy, such as an increase in pressure to a hazardous level, isolation of the equipment must be periodically verified until the maintenance or repair is completed, or until the possibility of such accumulation no longer exists. 
  • Return operating controls to neutral position after the test. A check of system activation (e.g. use of voltmeter for electrical circuits) should be performed to ensure isolation. 
  • The equipment is now locked out. 

Apply lockout and tag devices

  • Attach to isolating devices to prevent someone from restoring the energy flow
  • Lock out and tag the energy-isolating device with an assigned, individual lock. A worker will not be protected unless he/she uses his/her own padlock – with ONE KEY
  • If more than one worker is working on the same piece of equipment at the same time, each one should lock out the equipment, by placing a personal lock and tag on the group lockout device when he/she begins work, and should remove those devices when he/she stops working on the machine or equipment. 
  • Locks and tags should clearly show the name of the person who applied the device, the date, and the reason for the lockout. This identifies who is servicing the equipment. In a multiple lockout/Tagout situation, it will also identify any worker(s) who may not have finished working
  • Locks and tags must be durable enough to withstand the environment in which they are to be used. Information on the locks and tags should remain legible. 
  • Locks must be substantial enough to prevent removal without the use of excessive force. Tags must be substantial enough to prevent accidental or inadvertent removal. 
  • Both locks and tags are to be standardized by colour, shape, or size. Tags should be easily recognized and provide appropriate information about the lockout. 
  • For some equipment it may be necessary to construct attachments to which locks can be applied. An example is a common hasp to cover an operating button. 
  • Tags must be attached to the energy isolating device(s) and to the normal operating control in such a manner as to prevent operation during the lockout. 
  • Under normal circumstances, each person will remove his or her own lock either when it is safe to start the equipment, or at the end of a working day.
  • If a lock is still needed after the end of the shift, remove the lock only after someone on the next shift has applied a lock to replace it. This procedure must be continued, from shift to shift, as long as the equipment needs to remain locked out.

Control stored energy

  • Restrain hazardous energy
  • Make sure parts have stopped turning
  • Relieve trapped pressure – double block and blled
  • Install ground wires for charge dissipation
  • Block/support elevated equipment
  • Block all secondary sources of energy

Verify isolation of equipment

  • DO NOT take anything for granted
  • Double check your steps
  • Test before you work

Locking Out Portable Equipment

Usually portable equipment, whose energy source can be totally isolated by disconnecting a plug in cord, are not equipped with disconnects. If pulling the power cord from the outlet completely removes electrical energy to a machine or device, then you must do so before servicing the equipment. In certain cases use of a plug lockout device is highly recommended.


Locks – used for lockout should have a unique key, identify the person applying the lock (owner’s initials or employee number could be engraved on lock and key).

Hasps – whenever more than 1 person has to work on locked out equipment, a multiple locking device is used so each worker can secure their own safety

Lock Boxes – used for multiple workers with many lock out points

Tags – extra protection and provide vital information, NEVER substitute for lockout

Blanks – for piping

Covers – for connectors and valves

Chains – for valve handles

Removing a Lock

  • You are the only person who can remove a lock you applied
  • There is 1 exception – when you have left the site and it is necessary to remove the lock. A specific procedure must be followed in this situation – every possible effort must be made to contact you to ask if it is safe to remove the lock and operate the equipment
  • If you cannot be contacted, a qualified person must review the situation to determine if it is safe to remove the lock. If the qualified person can determine that it is safe for personnel to operate the equipment, the qualified person can authorize removal of the lock
  • Whenever it is necessary to remove your padlock when you cannot be contacted, you must be notified that your padlock has been removed before you resume work
  • When removing locks and tags – notify affected employees, check and re-check

Special Situations

  • In a situation where it is impossible to use a lock (when the disconnect is performed by pulling fuses or disconnecting electrical wires), attach a tag to the point of disconnection
  • The tag will indicate that a lockout is taking place in the form of a disconnection
  • A standby person must be posted where the circuit was opened. The standby will observe and prevent anyone from reapplying power to the disconnected equipment

Emergency Stops – E Stop

  • A Safety Control Device which has a different use than other devices that have been discussed. Most machines will have a number of E-Stop pushbuttons in different locations on the machine. Pushing any one of the E-Stop buttons quickly brings the machine to a stop.
  • Use E-Stops only for emergency situations to stop the machine quickly, once the E-Stop is pushed you can take a close look at the stopped equipment to locate the jam or find the problem.
  • If you need to reach into the machine to repair the problem, you must first isolate the equipment from all energy sources.

Typical Situation

One of the cartons in a case packaging line has fallen over. Since a fallen carton won’t fill correctly, it must be straightened or removed to prevent a machine malfunction or jam. The machine can be stopped quickly and safely to prevent damage by pushing one of the Emergency Stop push buttons.

Procedure for De-Energizing

Procedure for Re-Energizing

  • Energy is restored via the various disconnect devices used for isolation. 
  • Do a visual check of the area to confirm that no one is working on the equipment.
  • Before restoring any energy source, give a loud verbal “STAND CLEAR” warning that will be clearly heard by anyone liable to be affected by the energizing of the equipment.
  • When it is safe to do so, start the machine or process.


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