Summary of the 1910.147 Standard: The Control of Hazardous Energy

Key Takeaways

• OSHA 29 CFR 1910.147 applies to covered servicing and maintenance in general industry when unexpected energization, startup, or the release of stored energy could injure employees.
  

• There are some states that enforce their own lockout tagout rules, which may be stricter than federal OSHA standards.

• OSHA requires that lockout and tagout devices be identifiable, durable, standardized, substantial, and utilized exclusively for controlling energy.

• There are certain industries that follow specialized LOTO rules based on unique energy hazards and operational risks.

What is the OSHA 1910 Regulation?

OSHA 29 CFR 1910.147, The Control of Hazardous Energy (Lockout/Tagout), establishes minimum performance requirements for controlling hazardous energy during covered servicing and maintenance. It applies in general industry when unexpected energization, machine startup, or the release of stored energy could injure employees.

Normal production operations are generally outside the standard. However, servicing performed during production is covered when an employee must remove or bypass a guard or other safety device, or place part of the body into a point of operation or another danger zone during the machine's operating cycle. Minor tool changes, adjustments, and other minor servicing may qualify for the narrow exception only when the work is routine, repetitive, integral to production, and performed with alternative measures that provide effective protection.

The standard does not cover construction or agriculture employment; employment covered by 29 CFR Parts 1915, 1917, and 1918; certain electric-utility installations; electrical hazards covered by Subpart S; or oil and gas well drilling and servicing. Federal agencies operate under 29 CFR Part 1960, which requires agency occupational safety and health programs and compliance with applicable OSHA standards. OSHA-approved State Plans must be at least as effective as federal OSHA and may impose different or more stringent requirements.

Two limited activity exceptions also appear in 1910.147. Cord-and-plug equipment is outside the standard when unplugging controls the hazard and the plug remains under the exclusive control of the employee performing the work. Hot-tap work on pressurized transmission and distribution systems is excepted only when the employer demonstrates that continuity of service is essential, shutdown is impractical, and documented procedures and special equipment provide proven effective protection.

The decision tree below brings these scope rules together, showing when OSHA 1910.147 applies, when an exception may apply, and when another OSHA standard may govern the work. Use it as a quick reference, then confirm the applicable requirements against the standard and the conditions of the specific task.

Lockout Tagout Definition

Simply put, lockout/tagout is a safety procedure designed to control hazardous energy during servicing and maintenance of machines or equipment. Lockout devices, such as breaker locks, valve locks, locking hasps, or flange locks are physical locks that prevent machinery from being re-energized or opened to cause energy to be released. Meanwhile, tagout devices are prominent warning devices attached to energy-isolating devices to indicate that the equipment must not be operated until the tag is removed according to the established procedure.

Before we explore the 1910.147 standard further, let's define some other key terms:

Standard, OSHA Guidance, and Employer Practice

The regulatory text in 29 CFR 1910.147 establishes the enforceable requirements. OSHA interpretations, eTools, and publications help explain how the standard applies, but they do not replace the regulation. Employers may adopt practices that go beyond the minimum requirements when their equipment, processes, or workplace hazards call for additional controls.

Common Lockout Tagout Violations

Examples of conditions that can lead to citations under 29 CFR 1910.147 include failure to develop required energy control procedures, failure to provide required training, failure to conduct periodic inspections, use of noncompliant lockout/tagout devices, and failure to verify isolation and deenergization before servicing. For 2026, the maximum federal OSHA penalty is $16,550 per serious or other-than-serious violation and $165,514 per willful or repeated violation; actual proposed penalties depend on the citation and applicable penalty adjustments.

What Are the Key Elements of an Energy Control Procedure?

The lockout/tagout standard requires employers to develop, document, and use energy control procedures for covered servicing and maintenance. OSHA does not require a separate procedure for every individual machine when one procedure can safely cover similar machines or equipment, but the procedure must be specific enough to meet 29 CFR 1910.147(c)(4)(ii). Documentation may be omitted for a particular machine only when all eight conditions in the narrow exception under 29 CFR 1910.147(c)(4)(i) are met. A proper energy control procedure must include the following key elements:

• Statement of intended use of the procedure

• Specific procedural steps for shutting down, isolating, blocking, and securing equipment

• Specific procedural steps for the placement, removal, and transfer of lockout/tagout devices and assigned responsibilities

• Specific requirements for testing the equipment to verify the effectiveness of energy control measures

Energy control procedures must be clear and specific, and periodic inspections must identify and correct deviations or inadequacies. The standard also requires training that gives employees the knowledge and skills needed for their assigned roles.

Who Should Be Involved in the Lockout/Tagout Process?

The lockout/tagout process involves three groups of employees: authorized employees, affected employees, and other employees. The authorized employee is the person who is specifically trained and designated to perform the maintenance or repair work on the locked-out equipment. As shown in the image, authorized employees apply lockout or tagout devices while performing covered servicing or maintenance. Each device is normally removed by the employee who applied it; if that employee is unavailable, the employer may direct removal only under a documented procedure that provides equivalent safety and meets the requirements of 29 CFR 1910.147(e)(3).

An affected employee is an employee whose job requires operating or using a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or working in an area where that servicing or maintenance is being performed. OSHA requires affected employees to be notified before lockout or tagout controls are applied and after they are removed. Other employees whose work operations are or may be in an area where energy control procedures are used must be instructed about the procedure and the prohibition against restarting or reenergizing locked-out or tagged-out equipment.

Who Performs the Required Periodic Inspection of Energy Control Procedures?

The employer must inspect each energy control procedure at least annually. The inspection must be performed by an authorized employee other than the employee or employees using the procedure being inspected, and any deviations or inadequacies must be corrected.

For lockout procedures, the inspection includes a review of responsibilities with each authorized employee. For tagout procedures, it includes a review with each authorized and affected employee, including the limitations of tags. The employer must certify the inspection by identifying the machine or equipment, the inspection date, the employees included, and the person who performed it.

What Are the Requirements for Lockout/Tagout Devices?

To properly isolate energy sources, the standard requires lockout and tagout devices to be singularly identified, used only for controlling energy, and not used for other purposes. The devices must also meet these requirements:

1. Durable: Devices must withstand the environment to which they are exposed for the maximum expected period of use.

2. Standardized: Devices must be standardized within the facility by color, shape, or size. Tagout-device print and format must also be standardized.

3. Substantial: Lockout devices must resist removal without excessive force or unusual techniques. Tagout devices and their attachment means must prevent inadvertent or accidental removal.

4. Identifiable: Lockout and tagout devices must indicate the identity of the employee who applied them.

Tagout devices have additional requirements for warning legends, legibility, environmental resistance, and attachment strength.

Device selection should be based on the standard’s durability and substantiality requirements, not cost alone. Lockout devices must be substantial enough to prevent removal without excessive force or unusual techniques. Tagout attachment means must be non-reusable, attachable by hand, self-locking, non-releasable, and have a minimum unlocking strength of at least 50 pounds. Lockout and tagout devices must also withstand the environment in which they are expected to be used.

What Are the Training and Communication Requirements?

OSHA 1910.147 requires training so employees understand the purpose and function of the energy control program and can carry out their assigned responsibilities. Authorized employees must be trained to recognize applicable hazardous energy sources and understand the type and magnitude of the energy and the methods used to isolate and control it. Affected employees must be instructed in the purpose and use of the procedure, while other employees working in areas where energy control procedures may be used must understand the procedure and the prohibition against restarting or reenergizing locked-out or tagged-out equipment. 

When tagout systems are used, employees must also be trained on the limitations of tags, including that tags are warning devices and do not provide the physical restraint of a lock.

Retraining is required when job assignments, machines, equipment, processes, or energy control procedures change, or when an inspection or other information reveals gaps in an employee's knowledge or use of the procedure. Employers must certify that training is complete and current by recording each employee's name and training date.

How Does 1910.147 Relate to Other OSHA Standards?

Hazardous-energy requirements outside 1910.147 do not all relate to the general-industry standard in the same way. Some provisions add industry-specific requirements, while others govern work that 1910.147 expressly excludes.

Food Manufacturing Industry

Food manufacturing generally follows the general-industry lockout/tagout standard rather than a separate food-industry LOTO rule. The control of hazardous energy in the food manufacturing industry adheres to the general industry lockout tagout rule. However, due to the diverse and complex equipment used in food processing, standard LOTO protocols may need to be tailored to address specific energy control challenges. For example, a food-processing packaging line may require an energy control procedure that addresses multiple hazardous energy sources and specifies the shutdown, isolation, control of stored energy, and verification steps required before servicing begins.

FAQs on 29 CFR 1910.147

Does every machine need a written lockout/tagout procedure?

Employers generally must develop, document, and use an energy control procedure for covered servicing and maintenance. OSHA allows documentation to be omitted for a particular machine only when all eight conditions in the exception under 29 CFR 1910.147(c)(4)(i) are met. If even one condition is missing, the exception does not apply.

What is the formal name for OSHA’s lockout/tagout standard?

The formal name is "The Control of Hazardous Energy (Lockout/Tagout)" under 29 CFR 1910.147.

What does OSHA standard 1910.147 regulate?

It regulates the control of hazardous energy during the servicing and maintenance of machines and equipment to prevent unexpected startup or release of stored energy.

What is the difference between lockout and tagout?

Lockout involves placing a physical lock on an energy-isolating device to prevent operation, while Tagout uses warning tags to indicate that the equipment should not be operated, but it does not provide a physical barrier.

Does OSHA 1910.147 apply to construction?

No, OSHA 1910.147 applies to general industry, while lockout/tagout requirements for construction are covered under 29 CFR 1926.417 under Subpart K Electrical.