Course 621 Controlling Hazardous Energy (Lockout/Tagout)

The ECP is meant to keep workers safe from unexpected startup or release of energy.

Introduction to Rule Requirements

Energy Control Program (ECP) Purpose

Information about the Energy Control Program (ECP) can be found 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.

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 machines and equipment that could unexpectedly startup, become energized, or release stored energy, are isolated from their energy source(s) and rendered safe before service and maintenance are performed.

  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 used for the control of hazardous energy.
  2. Periodic inspections of the energy control procedures ensure 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 authorized, affected, and other employees understand the purpose and function of the energy control programs.

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1. Each of the following is one of the three core components of a Energy Control Program, EXCEPT _____.

a. energy control procedures
b. periodic inspections
c. Job Hazard Analysis
d. training and retraining

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Lockout/Tagout Definition

A raised forklift has stored potential energy. If it falls, the kinetic energy can kill the worker.

"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.

Potential energy transformed into kinetic energy.

Two States of Energy

Energy is the power for doing work. Energy exists in different types, but they are all 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.

  1. Potential Energy is stored energy that may be drawn upon to do work. Potential energy can be viewed as motion waiting to happen based on an object’s position, such as the energy found in elevated, suspended, compressed, or coiled materials. Potential energy can be converted to kinetic energy to do work.
  2. Kinetic Energy is energy resulting from moving objects, such as released loads, uncoiling springs, and moving machinery. When these objects are released, their potential energy converts to kinetic energy.

2. When a forklift is raised by a hoist, it has _____ energy. If it falls on a worker, the _____ energy can injure or kill.

a. lifted, quantum
b. potential, kinetic
c. kinetic, gravitational
d. moving, weight

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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 or 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 as a hoisted vehicles, raised dumpster lids, objects supported by a crane, and elevated dump truck beds. Gravitational energy is one form of potential energy.
  • 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.

3. Which of the following is an example of mechanical energy?

a. X-rays
b. Boiling water
c. Rotating wind turbine
d. Capacitors

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Energy Transformation

Coal-fired electrical power plant transforms chemical energy into electricity.

Energy is often converted from one type to another to make it more useful. For instance:

Power Plant

  • Chemical energy stored within a fuel such as coal is released as thermal energy when it is burned at a power plant.
  • This thermal energy is used to heat water within a boiler to create steam, which expands to rotate a turbine, generating electricity.
  • The electrical energy is then distributed along power lines to businesses where the electricity can be used to power commercial and residential users.

Air Compressor

  • An air compressor’s electric motor forces ambient air into a pressure vessel, confining large amounts of air into a small space for future use.
  • This stored air is pneumatic potential energy that can be used at a later time. During an electrical power failure, you can still use an air-powered tool, as long as sufficient potential pneumatic energy (compressed air) remains within the air compressor’s pressure vessel to operate the tool.

When Energy Becomes Hazardous

Energy becomes hazardous when it builds to a dangerous level or is released in a quantity that could injure a worker. Hazardous energy is never far from those who need to service or maintain equipment. Simply turning the power off does not make the equipment safe! It is critical that those who service or repair equipment know how hazardous energy could harm them and how to control it.

4. When energy is changed from one form to another, it is called energy _____.

a. transformation
b. intensification
c. entropy
d. actualization

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Lockout Vs. Tagout

Equipment capable of being locked out. If an energy isolating device can be locked out, the employer must use a lockout system unless the employer can prove that the tagout system will provide "full employee protection." Remember, if you can lock it out, do not tag it out.

Equipment not capable of being locked out. If the employer can prove that an energy isolating device is cannot be locked out, the employer must use a tagout system. To use a tagout system, the employer must meet the requirements for additional training and periodic inspections.

Lockout (LO), Tagout (TO), or Lockout/Tagout (LOTO)

Three choices, LO, TO, and LOTO.

You actually have three options when performing lockout/tagout:

Option 1: Lockout (LO): Lockout follows an established procedure for placing a lockout device such as a padlock on an energy-isolating device to create a physical barrier of protection. If an energy- isolating device can accept a lockout device, you must use lockout – no exceptions!

Option 2: Tagout (TO): Tagout is a procedure for placing a warning tag or sign – a tagout device – on an energy- isolating device that cannot accept a lockout device. Tagout devices must control hazardous energy at least as effectively as lockout devices. Since tagout devices do not provide the same physical barrier to hazardous energy as lockout devices, it is harder to ensure that they are equally effective. An additional measure of protection must be taken to provide equivalent protection. For this reason, some employers call this system "Tagout Plus."

Examples of additional tagout measures include removing a battery from a vehicle or removing the handle from a valve. A tagout device must be securely fastened to the energy-isolating device and must state that the equipment being serviced cannot be operated until it is removed.

Option 3: Lockout/Tagout (LOTO). As a best practice, many employers use a combination of lockout devices and tags commonly referred to as lockout/ tagout or LOTO. The lockout device, when secured on an energy-isolating device, provides the mandatory physical employee protection while the use of tags serves as both a visual and written notification to others. Remember, the use of lockout is the minimum requirement if an energy-isolating device can accept a lockout device.

Best Practice: Require authorized employees to attach a tag when securing the lockout device to the energy-isolating device. Provide custom tags that include the authorized employee’s picture.

5. When can an employer use a tagout system on equipment that is capable of being locked out?

a. When the employer can prove lockout is not possible
b. When the employer can prove full employee protection
c. When the employer can prove the scope of work is minimal
d. When the employer can prove lockout is inconvenient

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LOTO Procedure Elements

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Carefully develop and deploy lockout/tagout procedures.

Procedures for equipment with one or more sources of energy must detail the scope, purpose, authorization, rules and techniques that the employer will use to control hazardous energy.

  • Scope: The scope might be limited to a single or group of similar pieces of equipment or machinery.
  • Purpose: The purpose of the procedures is to ensure the unexpected energization/startup or shutdown does not occur during servicing or maintenance activities.
  • Authority: The responsible manager authorizes the procedures and ensures specific rules/techniques are listed within the procedures.

The procedures must state the means to be used to enforce compliance. This requirement is typically met by stating the procedure is mandatory and may result in disciplinary action.

At a minimum, the procedures must include the following:

  • a statement of the intended use of the procedure;
  • steps for shutting down, isolating, blocking, and securing equipment;
  • steps for the placement, removal, and transfer of lockout devices; and
  • test methods to verify equipment has reached a safe, zero energy state.

Best Practice: Place "machine-specific" lockout/tagout procedures at the location of the equipment. Include photographs of the energy-isolating devices specific to the equipment.

6. Where should written machine-specific lockout/tagout procedures be placed?

a. Within the facility of building
b. In a centralized workplace location
c. Where the equipment is located
d. In the safety office

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Unless the equipment meets the "8 exceptions" criteria, it must have a written procedure.

The Eight Exceptions

The employer must develop, document, and use a written LOTO procedure for servicing or maintenance of a machine or equipment unless ALL of the following eight exceptions exist:

  1. The machine or equipment has no potential for stored or residual energy or reaccumulation of stored energy after shut down which could endanger employees.
  2. The machine or equipment has a single energy source which can be readily identified and isolated.
  3. The isolation and locking out of the energy source will completely de-energize and deactivate the machine or equipment.
  4. The machine or equipment is isolated from the energy source and locked out during servicing or maintenance.
  5. A single lockout device will achieve a lock-out condition.
  6. The lockout device is under the exclusive control of the authorized employee performing the servicing or maintenance.
  7. The servicing or maintenance does not create hazards for other employees.
  8. The employer, in utilizing this exception, has had no accidents involving the unexpected activation or re-energization of the machine or equipment during servicing or maintenance.

Again, if the employer cannot meet the above exception criteria, they must develop and use written LOTO procedures.

New or Modified Equipment

All new machines and equipment, or all machines and equipment that undergo major repair, renovations or modification, must be equipped with energy-isolating devices capable of accepting a lockout device.

Whenever replacement or major repair, renovation or modification of a machine or equipment is performed, and whenever new machines or equipment are installed, energy isolating devices for such machine(s) or equipment must be designed to accept a lockout device.

7. If the employer has had previous accidents involving the unexpected startup of equipment, the employer _____.

a. must have written lockout/tagout procedures for the equipment
b. must have written procedures if the previous accidents were serious
c. may elect to have written procedures for the equipment
d. must conduct a Job Hazard Analysis on all equipment

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Lockout Devices

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Lockout Devices

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

They provide protection by physically preventing machines or equipment from becoming energized because they are substantial positive restraints that no one can remove without a key or other unlocking mechanism, or through extraordinary means, such as bolt cutters. The various types of lockout devices include:

  • Circuit Breaker Lockouts – Designed to help lock out most major brands of breakers. The goal of this product is to isolate a given breaker in a circuit breaker panel so that the entire breaker box does not need to be locked out.
  • Valve Lockouts – Designed to prevent fluid or gas valves from being opened while repair or maintenance is occurring. This could involve ball valves (handle you turn 90° to shut off) or gate valves (round knob). Ball valve lockouts are measured by the length of the handle. Gate valve lockouts are measured by the diameter of the knob.
  • Plug Lockouts – Helps lock out any electrical plug up to certain diameters
  • Electrical/Pneumatic Plugs – This multipurpose device can lock out electrical cords and male air hose connectors
  • Wall Switch Lockouts – Prevents workers from tampering with switches or accidental startup of equipment. Switch can be locked in the on or off position.
  • Adjustable Cable Lockouts – Comes with a cable that allows for locking out a wide variety of electrical or valve lockouts and accommodates multiple padlocks
  • Hasps – Allows more than one worker to put their padlock on an energy control device when more than one worker is performing maintenance on a given piece of equipment
  • Group Lock Boxes or Gang Boxes – Commonly used to lock out very large pieces of equipment that have multiple work functions affecting the maintenance of the equipment. These box allow for each lockout point to be secured with just one designated lock. The accompanying keys are then placed in the box. Each employee locks just one personal safety lock onto the box. The captured keys cannot be removed, or the equipment re-energized until all have removed their locks from the box.

See specific examples courtesy of DEenergize.

8. How do lockout devices physically prevent equipment and machines from being energized?

a. They must have a key to work
b. They require a substantial force
c. They provide a substantial positive restraint
d. They are controlled by authorized employees

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Tagout Devices

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If you can lock it out, don't just use a tag.

Tagout devices 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.

Tags are attached with plastic ties and must be hard to remove. There are specific requirements for the use of tagout devices:

  1. The tags must be attached where the lockout devices would be located.
  2. The employer must prove the tagout system will provide protection at least as effective as locks and will provide full employee protection.

The employer must demonstrate the protection achieved using tags is equivalent to the level of safety obtained by using locks. So, how do they do it? They must comply with all tagout-related provisions and also use additional safety measures that provide a level of safety equivalent to that obtained by using lockout.

Examples of additional safety measures include:

  • removing and isolating a circuit element;
  • blocking a controlling switch;
  • opening an extra disconnecting device; and
  • removing a valve handle to reduce the potential for any inadvertent energization while the tags are attached.

9. Where would you place tags during lockout/tagout of equipment and machinery?

a. Where each lockout device would have been placed
b. On the face of the equipment or machinery
c. In a prominent location so employees can best see them
d. On the warning tape surrounding the equipment or machinery

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Facts About Lockout/Tagout Devices

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Lockout/Tagout devices must substantial and durable.
Courtesy: Safety Signs

Lockout and tagout devices must meet the following criteria to ensure that they are effective and not removed inadvertently:

  • Durable: Lockout devices must work properly under the environmental conditions in which they are used. Warnings on tagout devices must be legible even in wet, damp, or corrosive conditions.
  • Standardized: Lockout and tagout devices must be designated by color, shape, or size. Tagout devices must have a standardized print and warning format.
  • Substantial: Lockout devices and tagout devices must be strong enough that they cannot be removed inadvertently. Tagout devices must be attached with a single-use, self-locking material such as a nylon cable tie with a minimum unlocking strength of 50 pounds.
  • Identifiable: Any employee who sees a lockout or tagout device must recognize who attached it and understand its purpose. The device must not be used for purposes other than the control of hazardous energy.
  • Unique: Each lock must have a unique key; this means that only the employee who uses the lock has the key to that lock.
  • Payment: If you are an employer, you must provide lockout and tagout devices to employees who need to shut down equipment to service or maintain it.

10. Which of the following is NOT a criteria for tagout device ties?

a. They must be single-use
b. They must be color coded with red stripes
c. They must have a minimum unlocking strength of 50 pounds
d. They must be made of self-locking material

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If you have time, watch this Graphic Products video to learn about Lockout Tagout – the process of disabling machinery or equipment, thus preventing release of hazardous energy during servicing and maintenance activities. Get a LO/TO Best Practice Guide.

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