According to OSHA (The Occupational Health and Safety Administration) approximately 3 million workers in the US service equipment and face the greatest risk of injury if Lockout/Tagout is not properly implemented. Lockout/Tagout prevents an estimated 120 facilities and 60,000 injuries each year in US alone.

The US Government created under the Occupational Safety and Health Act in 1970; this is the government regulatory agency for workplace safety. It instructs, conducts inspections and enforces workplace safety.

As per OSHA: “each employer shall furnish to each of his employees employment and place of employment  which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees.”

The Lockout/Tagout Standard is a necessary provision, as it protects against the physical hazards that result in grave consequences due to the intense power of some machinery. Complying with OSHA’s Lockout/Tagout program not only protects employers from a violation citation but, more importantly, protects employees from serious physical hazards.

Who Can Perform a Lockout?

The standard gives each employer the flexibility to develop an energy control program suited to a specific workplace and the equipment being used, maintained and serviced. The program is designed to cover three categories of employees:

Authorized employee: An employee who locks or tags machines and equipment to perform servicing or maintenance.

Affected employee: An employee who performs duties in an area that requires him or her to lock out or tag out machines or equipment for authorized personnel to perform servicing or maintenance on that machine or equipment.

Other employees: All employees who are or may be in an area where energy control procedures may be used must receive instruction regarding the energy-control procedure. Employees need to be instructed that it is strictly prohibited to remove a Lockout or Tagout device and then attempt to restart, re-energize or operate the machinery.

In addition to protecting employees, the Lockout/Tagout Standard can help cut costs and improve productivity, as well as reduce incidents, lower and reduce indirect costs and costs from Lockout/Tagout injuries, and decrease equipment downtime.

Sequence of Lockout or Tagout System Procedure

  • Notify all affected employees that a lockout or Tagout systems are going to be utilized and the reason therefore.  The authorized employee shall know the type and magnitude of energy that the machine or equipment utilizes and shall understand the hazards thereof.
  • If the machine is operating, shut it down by the normal stopping procedure (depress stop button, open toggle switch, etc.).
  • Operate the switch valve or other energy isolating device so that the equipment is isolated from its energy source(s).  Stored energy (such as that in springs, elevated machine members, rotating flywheels, hydraulic systems, and air, gas, steam, or water pressure, etc.) must be dissipated or restrained by methods such as repositioning, blocking, bleeding down, etc.
  • After ensuring that no personnel are exposed, and as a check on having disconnected the energy sources, operate the push button or other normal operating controls to make certain the equipment will not operate.
  • The equipment is now locked out or tagged out.

Lockout/Tagout Procedure

OSHA 1910.147 (d) requires that control of hazardous energy be done according to a six step procedure

  • Prepare for Shutdown
  • Shutdown Equipment
  • Isolate all energy sources
  • Application of  Locks & Tags
  • Release Stored Energy
  • Equipment Isolation verification

Prepare for Shutdown

Before an authorized or Affected Employee turns off a machine or equipment, the Authorized Employee shall have knowledge of the type and magnitude of the energy, the hazards of the energy to be controlled, and the method or means to control the energy.


Shutdown Equipment


The machine or equipment shall be turned off or shut down using the procedures established for the machine or equipment. An orderly shutdown must be utilized to avoid any additional or increased hazard(s) to employees as a result of the equipment stoppage.


Isolate all energy sources


All energy isolating devices that are needed to control the energy to the machine or equipment shall be physically located and operated in such a manner as to isolate the machine or equipment from the Energy Source(s).


Application of Locks and Tags


  • Lockout or Tagout devices shall be affixed to each energy isolating device by authorized employees.
  • Lockout devices, where used, shall be affixed in a manner to that will hold the energy isolating devices in a "safe" or "off" position.
  • Tagout devices, where used, shall be affixed in such a manner as will clearly indicate that the operation or movement of energy isolating devices from the "safe" or "off" position is prohibited.
  • Where Tagout devices are used with energy isolating devices designed with the capability of being locked, the tag attachment shall be fastened at the same point at which the lock would have been attached.
  • Where a tag cannot be affixed directly to the energy isolating device, the tag shall be located as close as safely possible to the device, in a position that will be immediately obvious to anyone attempting to operate the device


Release of Stored Energy


Take any of the following steps that are necessary to guard against energy left in the equipment after it has been isolated from its energy sources.

  • Inspect the system to make sure all parts have stopped moving.
  • Install ground wires.
  • Relieve trapped pressure.
  • Release the tension on springs, or block the movement of spring-driven parts.
  • Block or brace parts that could fall because of gravity.
  • Block parts in hydraulic and pneumatic systems that could move from the loss of pressure.
  • Bleed the lines and leave vent valves open.
  • Drain process piping systems and close valves to prevent the flow of hazardous materials.
  • If a line must be blocked where there is no valve, use a blank flange.
  • Purge reactor tanks and process lines.
  • Dissipate extreme cold or heat, or wear protective clothing.
  • If stored energy can reaccumulate, monitor it to make sure it stays below hazardous levels.


Equipment-Isolation Verification


Take any of the following steps that suits company’s equipment and energy control program.

  • Make sure all danger areas are clear of personnel.
  • Verify that the main disconnect switch or circuit breaker can’t be moved to the “on” position.
  • Use a voltmeter or other equipment to check the switch.
  • Press all start buttons and other activating controls on the equipment itself to ensure that it is isolated.
  • Shut off all machine controls when the testing is finished.

What’s the Procedure for Removal of Locks and Tags?

Before Lockout or Tagout devices are removed and energy is restored to the machine or equipment, take the following actions or observe the following procedures:

  • Inspect the work area to ensure that non-essential items have been removed and that machine or equipment components are intact and capable of operating properly;
  • Check the area around the machine or equipment to ensure that all employees have been safely positioned or removed,
  • Make sure that locks or tags are removed ONLY by those employees who attached the locks or tags; and
  • Notify affected employees after removing locks or tags and before starting equipment or machines.

Responsibilities of individuals in Lockout/Tagout

Environmental Health & Safety Responsibilities

  • Coordinate the Lockout/Tagout program;
  • Training & assistance with annual inspections;
  • Maintain copies of equipment specific lockout procedures, annual inspections & training records; and
  • Update & evaluate the Lockout/Tagout program annually.

Supervisor’s Responsibilities

  • Complete equipment specific Lockout/Tagout procedures;
  • Conduct annual & periodic inspections;
  • Keep a list of authorized employees;
  • Issue Lockout/Tagout devices to employees;
  • Ensure all affected employees are properly trained on Lockout/Tagout procedures;

Authorized Employee Responsibilities

  • Attend EH & S’s required training;
  • Follow all Lockout/Tagout procedures;
  • Assist supervisor’s in completing equipment specific Lockout/Tagout procedures;
  • Consult supervisors when questions or concerns arise; and
  • Notify all affected employees of Lockout/Tagout activities.