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Course 710 - Energy Control Program (Lockout/Tagout)

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Purpose, Scope, and Application

Purpose of the Energy Control Program (ECP)

Information about the Energy Control Program (ECP) is contained in 29 CFR 1910.147, Control of Hazardous Energy (Lockout/Tagout).

The purpose of the ECP is to provide written policies and rules within your safety management system that help prevent injury to workers due to the unexpected startup of machines and equipment, or release of stored energy.

Check out this short audio clip by Dan Clark of the theSafetyBrief.com that gives a good introduction about the importance performing lockout/tagout at work.

Scope of Lockout/Tagout Rule

Employers must establish an Energy Control Program (ECP), consisting of three core components: energy control procedures; employee training; and periodic inspections to ensure that before service and maintenance is performed, machines and equipment that could unexpectedly startup, become energized, or release stored energy, are isolated from their energy source(s) and rendered safe.

  1. Energy control procedures detail and document the specific information that an authorized employee must know to accomplish lockout/tagout, i.e., the scope, purpose, authorization rules and techniques to be utilized for the control of hazardous energy.

  2. Periodic inspections of the energy control procedures ensure that the procedures are effective and the requirements of the standard are being followed.

  3. Employee training and retraining, along with additional training under a tagout system, ensure that the purpose and function of the energy control programs are understood by the authorized, affected and other employees.

What is lockout/tagout?

"Lockout/tagout" (LOTO) refers to specific practices and procedures to safeguard employees from the unexpected energization or startup of machinery and equipment, or the release of hazardous energy during service or maintenance activities.

The standard requires, in part, that a designated individual turns off and disconnects the machinery or equipment from its energy source(s) before performing service or maintenance. It also requires that an authorized employee(s) either lock or tag the energy-isolating device(s) to prevent the release of hazardous energy and take steps to verify that the energy has been isolated effectively.

If the potential exists for the release of hazardous stored energy or for the reaccumulation of stored energy to a hazardous level, the employer must ensure that the employee(s) take steps to prevent injury that may result from the release of the stored energy.

Lockout Devices

Lockout devices, typically locks, hold energy-isolation devices in a safe or "off" position.

They provide protection by preventing machines or equipment from becoming energized because they are positive restraints that no one can remove without a key or other unlocking mechanism, or through extraordinary means, such as bolt cutters.

Tagout Devices

Tagout devices, by contrast, are prominent warning devices that an authorized employee fastens to energy-isolating devices to warn employees not to re-energize the machine while he or she services or maintains it.

Tagout devices are easier to remove and, by themselves, provide employees with less protection than do lockout devices.


Performing LOTO Procedures

Whenever your employees perform servicing and/or maintenance on machines or equipment, they can be exposed to the unexpected energization, startup, or release of hazardous energy. Hazardous energy sources include electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other forms of harmful energy.

Servicing or Maintenance

Servicing or maintenance refers to constructing, installing, setting up, adjusting, inspecting, modifying, maintaining and/or servicing machines or equipment, including lubrication, cleaning or unjamming of machines or equipment, and making adjustments or tool changes, where workers could be exposed to the unexpected energization or startup of the equipment or release of hazardous energy.

What's "Unexpected?"

The term "unexpected" also covers situations in which the servicing and/or maintenance is performed during ongoing normal production operations if:

  • A worker is required to remove or bypass machine guards or other safety devices; or
  • A worker is required to place any part of his or her body into a point of operation or into an area on a machine or piece of equipment where work is performed, or into the danger zone associated with the machine's operation.

Passive monitoring during normal production operations is generally not considered a servicing or maintenance activity when the above criteria is not met.

What is Hazardous Energy?

Energy in any form becomes hazardous when it builds to a dangerous level or is released in a quantity that could injure a worker. Workers servicing or maintaining machines or equipment may be seriously injured or killed if hazardous energy is not properly controlled. Injuries resulting from the failure to control hazardous energy during maintenance activities can be serious or fatal! Injuries may include electrocution, burns, crushing, cutting, lacerating, amputating, or fracturing body parts, and others.

  • A steam valve is automatically turned on burning workers who are repairing a downstream connection in the piping.
  • A jammed conveyor system suddenly releases, crushing a worker who is trying to clear the jam.
  • Internal wiring on a piece of factory equipment electrically shorts, shocking worker who is repairing the equipment.

Forms of Energy - Electricity is not the only hazard!

Potential energy is converted into kenetic energy.
Electricity is not the only hazard!
(Click to enlarge)

Energy is the power for doing work. Energy exists in different types, but all are associated with motion. Regardless of the type, energy exists in two basic states: potential energy and kinetic energy. Tensioned objects such as suspended loads have potential energy – energy that has the opportunity for motion.

Releasing the load converts potential energy to kinetic energy, causing the load to drop.

Types of Energy

It's important to understand that electricity is not the only form of hazardous energy employees may encounter during lockout/tagout. Main energy sources that supply power to the entire machine or equipment may be electrical, but secondary energy sources such as pneumatic or mechanical energy may still be stored with the potential to cause injury. One of more of the following types of energy may require deenergization to completely isolate the equipment.

Electricity is not the only hazard!
(Click to enlarge)
  • Chemical. Liquids, such as gasoline, diesel, benzene, acids, and caustics. Gases, such as propane, natural gas, and methane. Solids, such as fertilizer, wet and dry cell batteries, and combustible dust.
  • Electrical. Alternating (AC) and direct (DC) currents. Includes equipment and conductors at both household and industrial-voltages, photovoltaic systems, circuit breakers, transformers, capacitors, inverters, motors, and hybrid vehicles.
  • Gravitational. Objects such a hoisted vehicles, raised dumpster lids, objects supported by a crane, and elevated dump truck beds.
  • Hydraulic. Pressurized hydraulic systems, including hoses, pumps, valves, actuators, and reservoirs such as those on a forklift, in an automotive vehicle hoist, power press equipment, or an injection molding machine.
  • Mechanical. Sources such as a breeze rotating a wind turbine, water moving a paddle wheel, vehicle/mobile equipment movement, and a spring under compression. Extreme sound is also a hazardous mechanical energy.
  • Pneumatic. Pressurized air or gas systems, including pipes, pumps, valves, actuators, and pressure vessels such as those found in coating or pesticide sprayers, air compressors, and tank and pipe purging systems.
  • Radiant. Energy that travels by waves or particles, particularly electromagnetic radiation such as heat or x-rays. Ionizing radiation includes alpha and beta particles,computed tomography (CT) and X-rays. Non-ionizing radiation includes lasers, radio frequency (RF), and microwave (MW).
  • Thermal. Hot water, heated oil, steam, and equipment need time to cool, while liquefied gases, such as nitrogen, need time to warm to safe thermal levels.
  • Explosive. The rapid increase in the volume of energy with the generation of high temperatures and the release of gases. Supersonic explosions are called detonations. Subsonic explosions are called deflagration. A boiling liquid expanding vapor explosion is called (BLEVE) .


This Pipeline Safety video is a great tailgate safety meeting discussion starter.


Before beginning this quiz, we highly recommend you review the module material. This quiz is designed to allow you to self-check your comprehension of the module content, but only focuses on key concepts and ideas.

Read each question carefully. Select the best answer, even if more than one answer seems possible. When done, click on the "Get Quiz Answers" button. If you do not answer all the questions, you will receive an error message.

Good luck!

1. The purpose of Lockout/Tagout to prevent injury due to the _____ startup of machines and equipment or the release of stored energy.

2. Which device is a positive restraint that locks and holds energy-isolation devices in a safe or "off" position to prevent machines or equipment from becoming energized?

3. Which of the following is NOT considered a form of energy addressed in the Energy Control Program?

4. Which device is used to warn employees not to re-energize the machine while he or she services or maintains it?

5. All of the following are examples of "servicing or maintenance," EXCEPT _____.

Have a great day!

Important! You will receive an "error" message unless all questions are answered.