Lockout/Tagout (LOTO): OSHA Requirements, Procedures, and Safety Guide

Lockout/tagout (LOTO) is an essential workplace safety practice that helps protect employees from unexpected machine startup and hazardous energy release during maintenance and servicing. Understanding OSHA lockout/tagout requirements, proper energy isolation procedures, and employee responsibilities can help workplaces reduce risks and maintain safer working conditions.

In this guide, you'll learn what lockout/tagout means, when it is required, how the LOTO procedure works, and what employees and employers need to know about energy control and safety training.

What Is Lockout/Tagout (LOTO)?

Lockout/tagout (LOTO) is a workplace safety procedure used to prevent machinery from starting unexpectedly or releasing hazardous energy while employees perform covered servicing or maintenance.

Equipment may contain electrical energy, hydraulic pressure, compressed air, steam, mechanical movement, or stored energy. Simply switching off a machine may not eliminate these hazards. A proper energy control procedure isolates the equipment, secures the isolation points, controls stored energy, and verifies that the equipment is safe before work begins.

The purpose of lockout/tagout is to protect workers from injuries caused by unexpected energization, startup, or the release of hazardous energy.

For general industry, OSHA's primary lockout/tagout standard is 29 CFR 1910.147, known as The Control of Hazardous Energy. Construction work may be governed by different applicable standards.

What Does Lockout/Tagout Mean?

Lockout/tagout combines two methods for communicating and controlling hazardous energy: lockout and tagout.

What Is Lockout?

Lockout involves placing a lockout device on an energy-isolating device to prevent it from being operated. The device remains secured until it can be removed according to the applicable energy control procedure.

For example, a maintenance worker may isolate electrical power to a conveyor and apply a personal lock before repairing it.

What Is Tagout?

Tagout involves attaching a warning tag to an energy-isolating device to indicate that equipment must not be operated. The tag alerts employees to the hazard but does not physically restrain the isolation point in the same way as a lock.

Under OSHA's general industry standard, lockout is generally required when an energy-isolating device can be locked out, subject to the standard's requirements and applicable exceptions.

What Is the Difference Between Lockout and Tagout?

Both methods must be part of an effective energy control program. A tag alone should not be treated as proof that equipment is safe.

What Is the Purpose of LOTO?

The purpose of a lockout/tagout procedure is to protect employees from hazardous energy during covered servicing and maintenance.

Prevent Unexpected Machine Startup

Machinery can restart when another worker presses a button, restores power, or activates a remote control. Energy isolation helps prevent the equipment from operating while maintenance is underway.

Control Hazardous and Stored Energy

Equipment can retain energy even after its main power supply has been disconnected. Examples include compressed air, hydraulic pressure, charged electrical components, tensioned springs, and elevated machine parts.

A safe energy control procedure identifies these hazards and explains how they must be released, disconnected, restrained, or otherwise controlled.

Protect Maintenance Employees

Workers repairing, cleaning, adjusting, or unjamming machinery may be exposed to moving parts or unexpected energy release. Lockout/tagout helps reduce these risks when applied correctly.

Support OSHA Compliance

Employers should identify the safety standards that apply to their operations, establish the required procedures, train employees, and inspect their energy control programs.

When Is LOTO Required?

Under OSHA's general industry standard, lockout/tagout generally applies when employees perform covered servicing or maintenance and unexpected energization, startup, or the release of stored energy could cause injury.

Examples include:

• Repairing industrial machinery.

• Servicing conveyor systems.

• Maintaining hydraulic or pneumatic equipment.

• Cleaning or unjamming machinery when employees may be exposed to hazardous energy.

• Replacing machine components.

• Performing covered maintenance that exposes employees to unexpected equipment movement.

The standard includes specific scope limitations and exceptions, so not every task automatically requires the same procedure. Employers must assess the equipment, work activity, and applicable requirements.

Important: OSHA 29 CFR 1910.147 excludes construction employment from its scope. Construction employers should identify the construction standards and other requirements that apply to their specific activities instead of assuming the general industry standard governs every construction task.

What Are OSHA Lockout/Tagout Requirements?

OSHA's general industry requirements address energy control programs, equipment-specific procedures, devices, employee training, and periodic inspections.

Energy Control Program and LOTO Policy

Employers covered by the standard must establish an energy control program. Where required, written procedures must explain how hazardous energy will be controlled before servicing begins.

The program should address the equipment, energy sources, isolation points, device application, stored energy controls, verification, and safe restoration of equipment.

OSHA Lockout Tag Requirements

Lockout and tagout devices must be suitable for their intended purpose and meet the applicable requirements. Tags must clearly communicate that equipment must not be operated and must be used according to the energy control procedure.

Employees should never bypass, ignore, or remove another person's lock or tag outside the authorized process.

Energy Control Procedures

Energy control procedures explain how employees safely shut down equipment, isolate energy sources, apply devices, address stored energy, and verify isolation.

Procedures should be specific enough for employees to identify the correct isolation points and follow the required steps without relying on assumptions.

OSHA LOTO Inspection and Compliance

Under the general industry standard, employers must conduct periodic inspections of energy control procedures at least annually. These inspections must meet OSHA's requirements, including the specified role of the authorized employee conducting the inspection.

Employers should correct identified deficiencies and provide additional training when required by changes in assignments, equipment, procedures, or observed problems.

How Does a Lockout/Tagout Procedure Work?

The precise procedure depends on the equipment and its energy sources. A typical process includes the following steps.

Step 1: Prepare for Shutdown

Identify the equipment, energy sources, associated hazards, and the appropriate isolation procedure. Notify affected employees that the equipment will be shut down.

Step 2: Shut Down the Equipment

Stop the machine using the established shutdown method. Follow the equipment-specific procedure to avoid creating additional hazards.

Step 3: Isolate All Relevant Energy Sources

Operate the appropriate energy-isolating devices. A normal stop button may not disconnect equipment from hazardous energy, so employees must use the isolation points specified in the procedure.

Step 4: Apply Lockout or Tagout Devices

Authorized employees apply the required devices to the energy-isolating points. Each device must be used according to the applicable procedure and standard.

Step 5: Control Stored Energy

Release, disconnect, restrain, or otherwise control stored energy as required. This may involve relieving hydraulic pressure, draining compressed air, discharging stored electrical energy, or securing elevated components.

If hazardous energy could build up again, the procedure must address continued verification or additional protective measures.

Step 6: Verify Energy Isolation

Before work begins, the authorized employee verifies that the equipment has been isolated and deenergized as required. The verification method depends on the equipment and the hazards involved.

Never assume that equipment is safe merely because a switch is off or a warning tag is visible.

Step 7: Restore Equipment Safely

When maintenance is complete, follow the required release procedure. Inspect the work area, ensure tools and nonessential items are removed, confirm that employees are safely positioned, and follow the applicable device-removal and restart steps.

Locks are normally removed by the employees who applied them. OSHA's general industry standard permits a specific exception when that employee is unavailable, provided the employer follows the required safeguards and procedures.

Who Is an Authorized Employee Under LOTO?

An authorized employee applies lockout or tagout devices to perform covered servicing or maintenance, or carries out the energy control duties defined by the applicable requirements.

Authorized employees need to understand the equipment's energy sources, isolation points, stored energy hazards, device application, and verification methods. They must follow the relevant procedures before beginning covered work.

What Is an Affected Employee's Responsibility During Lockout/Tagout?

An affected employee operates or uses equipment being serviced under LOTO, or works in an area where the servicing or maintenance takes place.

An affected employee's responsibilities include:

• Understanding why equipment has been locked or tagged out.

• Following instructions under the workplace energy control program.

• Never restarting or reenergizing protected equipment.

• Respecting restrictions around the maintenance area.

• Reporting unsafe conditions or attempts to bypass safety controls.

An affected employee may become an authorized employee if their duties change to include covered servicing or maintenance and they receive the required training.

What Is the Final Step in Lockout/Tagout De-Energization?

Before servicing begins, the final key step is to verify that the equipment has been isolated and hazardous energy has been controlled according to the applicable procedure.

This verification follows shutdown, energy isolation, application of devices, and control of stored energy. Restoring power after maintenance is a separate process with its own required safety checks.

Where Should Tagout Devices Be Applied?

Tagout devices should be applied to the energy-isolating devices identified in the applicable procedure, in a position where the warning is clear and the device can be securely attached.

The correct location depends on the equipment and energy source. A tag attached to an ordinary operating button does not necessarily isolate hazardous energy. Employees should follow the equipment-specific procedure.

What Does an Energy Control Program Include?

An energy control program includes procedures for controlling hazardous energy, employee training, and periodic inspections as required by the applicable standard.

Its procedures explain how equipment is shut down, isolated, secured, checked, and safely returned to service. They should also address stored energy, employee responsibilities, and how deficiencies are corrected.

What Are Common LOTO Violations?

Common lockout/tagout problems include:

• Relying only on the stop button instead of isolating energy.

• Failing to identify every hazardous energy source.

• Ignoring stored pressure or mechanical energy.

• Using unsuitable devices or unclear tags.

• Skipping the required verification step.

• Removing another employee's lock without following the required process.

• Failing to provide role-appropriate employee training.

Employers can reduce these risks through suitable procedures, effective training, required inspections, and prompt correction of unsafe practices.

Why Is Lockout/Tagout Training Important?

LOTO training helps employees recognize hazardous energy, understand their responsibilities, and follow safe energy control procedures.

Authorized employees need the knowledge and skills required for their assigned energy control duties. Affected employees must understand the purpose of the procedure and the prohibition against restarting or reenergizing protected equipment. Other employees must receive the instruction required for their roles under the applicable standard.

Workers looking to build broader workplace safety knowledge can explore OSHA 10-hour safety training. Supervisors and workers seeking broader safety education can also review OSHA 30-hour training.

These courses provide broader safety education and should not automatically be treated as a substitute for task-specific LOTO training when it is required.

For more workplace safety learning resources, visit Get OSHA Courses.

Frequently Asked Questions

What is another name for lockout/tagout?

Lockout/tagout is also known as LOTO or hazardous energy control. It refers to procedures designed to prevent unexpected energization, startup, or the release of hazardous energy during covered work.

What does the OSHA lockout/tagout rule protect workers from?

The applicable energy control requirements help protect employees from injuries caused by unexpected machine startup, energization, or the release of stored energy during covered servicing and maintenance.

Who is authorized to remove a lockout/tagout device from a machine?

Normally, the employee who applied the device removes it. OSHA's general industry standard provides a specific exception when that employee is unavailable, subject to the required employer procedures and safeguards.

How often must employers review their energy control procedures?

OSHA's general industry standard requires periodic inspections at least annually. Employers must follow the standard's inspection requirements and address any deficiencies identified.

Is LOTO required for every machine repair?

Not necessarily. Requirements depend on the equipment, work activity, hazards, and applicable standard. Employers must determine whether the work falls within the relevant energy control requirements.

What is the final step of lockout/tagout de-energization?

Before covered work begins, employees must verify that the equipment has been isolated and hazardous energy controlled as required by the procedure. Equipment restoration after maintenance is a separate process.

Is OSHA 10 or OSHA 30 training the same as LOTO training?

No. OSHA 10- and 30-hour Outreach Training provides broader workplace safety education. It does not automatically replace the LOTO-specific instruction required for an employee's duties.

Which government entity establishes lockout/tagout requirements?

In the United States, OSHA establishes and enforces applicable workplace safety standards. The specific requirements depend on the type of work and the standard that applies.

Conclusion

Lockout/tagout is an important safety practice for preventing unexpected machine startup and hazardous energy release during covered servicing and maintenance.

An effective program combines appropriate energy isolation, suitable devices, stored energy controls, verification, employee training, and required inspections. Employers should identify the standards that apply to their operations and ensure that workers understand their responsibilities.

Consistent energy control procedures help reduce workplace risks and support safer maintenance practices.