Control of Hazardous Energy (Lockout/Tagout)

Control of Hazardous Energy (Lockout/Tagout) is the OSHA general industry standard that protects workers who service and maintain machines and equipment. It requires employers to keep equipment in a safe, de-energized state while work is done, so that an unexpected start-up or a release of stored energy cannot injure the people working on it.

The rule matters because servicing work often means removing guards, reaching into machines and opening lines that hold pressure. Any general industry employer whose employees perform that kind of work must have a written energy control program, trained employees and annual inspections. It is also one of OSHA's most frequently cited standards.

What Is the Control of Hazardous Energy Standard?

The standard is codified at 29 CFR 1910.147, in Subpart J (General Environmental Controls) of OSHA's general industry rules. It was published in 1989 and covers the servicing and maintenance of machines and equipment where unexpected energization, start-up or release of stored energy could cause injury.

A few definitions drive the whole standard:

• Energy source: any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal or other energy.
• Energy isolating device: a mechanical device that physically prevents the transmission or release of energy, such as a disconnect switch, a line valve or a block. Push buttons, selector switches and other control circuit devices do not count.
• Lockout device: a lock or similar positive means that holds an isolating device in the safe position.
• Tagout device: a prominent warning tag and attachment that indicates the equipment must not be operated until the tag is removed.

For a plain-language overview, see the glossary entry on lockout/tagout (LOTO).

Who Must Comply?

The standard applies to general industry employers whose employees service or maintain machines or equipment. Under 1910.147(a)(1)(ii), it does not cover construction and agriculture, maritime employment under Parts 1915, 1917 and 1918, electric utility power generation, transmission and distribution installations, exposure to electrical hazards from work on, near or with conductors or equipment in electric-utilization installations (covered by Subpart S), or oil and gas well drilling and servicing.

Normal production operations are generally outside the standard. Servicing during production is covered when an employee must remove or bypass a guard or safety device, or place any part of the body in a point of operation or danger zone. Minor tool changes and adjustments that are routine, repetitive and integral to production are excluded if alternative measures provide effective protection.

Two other exclusions in 1910.147(a)(2)(iii) come up often:

• Work on cord and plug connected equipment when it is unplugged and the plug stays under the exclusive control of the employee doing the work.
• Hot tap operations on pressurized pipelines for gas, steam, water or petroleum products, when continuity of service is essential, shutdown is impractical, and documented procedures and special equipment provide effective protection.

In states with an OSHA-approved State Plan, the state program enforces its own rule, which must be at least as effective as the federal standard and may be stricter.

Key Requirements

Energy control program, 1910.147(c)(1)

Employers must establish a program made up of three parts: documented energy control procedures, employee training and periodic inspections.

Lockout first, tagout only when justified, 1910.147(c)(2) and (c)(3)

If an energy isolating device can accept a lock, the employer must use lockout unless it can demonstrate that a tagout program gives full employee protection. Full protection means the tag is attached where the lock would go and the employer adds measures such as removing an isolating circuit element, blocking a controlling switch or opening an extra disconnect. Since January 2, 1990, replaced, repaired, renovated or modified equipment and new machines must be designed to accept a lockout device.

Written procedures, 1910.147(c)(4)

Procedures must be developed, documented and used for each piece of equipment. Each must state its intended use and lay out the specific steps for shutting down, isolating, blocking and securing equipment, placing and removing locks and tags, and testing to verify isolation. A narrow exception in the note to (c)(4)(i) lets an employer skip documenting a procedure only when all eight listed conditions are met, including a single readily identified energy source, no stored energy, and no prior accidents involving unexpected activation.

Devices, 1910.147(c)(5)

The employer provides locks, tags, chains, wedges and other hardware. Devices must be used only for energy control and must be durable, standardized, substantial and identifiable to the employee who applied them. Tag attachments must be non-reusable, self-locking and have an unlocking strength of no less than 50 pounds.

Application and release of control, 1910.147(d) and (e)

Paragraph (d) sets the application sequence: prepare for shutdown, shut down, isolate, apply locks or tags, relieve or restrain stored energy, and verify isolation before work starts. Paragraph (e) covers release: inspect the work area, make sure employees are clear, notify affected employees, and have each device removed by the employee who applied it. Removal by someone else is allowed only under a documented employer procedure that verifies the authorized employee is not at the facility, makes reasonable efforts to reach them, and informs them before they resume work.

Contractors, groups and shift changes, 1910.147(f)

Host employers and outside servicing contractors must inform each other of their lockout/tagout procedures. Group lockout must give each authorized employee protection equal to a personal lock, typically by having every worker attach a personal device to a group lockbox. Specific procedures must maintain protection across shift and personnel changes.

Training, Inspection and Records

• Training, 1910.147(c)(7): Authorized employees learn to recognize hazardous energy sources, the type and magnitude of energy, and the isolation methods. Affected employees learn the purpose and use of procedures. All other employees in the area learn not to restart locked or tagged equipment. Where tagout is used, employees must also learn the limitations of tags.
• Retraining: Required when job assignments, machines, equipment or processes change in a way that creates a new hazard, when procedures change, or when an inspection or other information shows deviations or gaps in knowledge.
• Training certification: The employer must certify that training is complete and up to date, including each employee's name and dates of training.
• Periodic inspection, 1910.147(c)(6): At least annually, an authorized employee other than the ones using the procedure inspects each energy control procedure to correct deviations. For lockout, the inspection includes a review of responsibilities with each authorized employee. For tagout, it includes affected employees too.
• Inspection certification: Each inspection must be certified with the machine or equipment, the date, the employees included and the person who performed it.

Common Violations and Penalties

In OSHA's preliminary fiscal year 2026 list of the top 10 most frequently cited standards, the control of hazardous energy ranks third. Typical findings include:

• No documented, equipment-specific procedures, or generic procedures that miss energy sources.
• Annual periodic inspections not performed or not certified.
• Training not provided to affected and other employees, or no training certification.
• Using tagout on devices that can be locked out without full employee protection measures.
• Skipping the verification step or failing to relieve stored energy.

According to OSHA's penalties page, for penalties assessed after January 15, 2026 the maximum is $16,550 per serious or other-than-serious violation and $165,514 per willful or repeated violation. State Plan states set their own amounts.

OSHA's regulatory agenda published in July 2026 listed a proposed update to the lockout/tagout standard, including how to address computer-based controls of hazardous energy. As of this writing the 1989 rule remains in force. Check the Federal Register for the current status before relying on any change.

How to Comply: Step by Step

1. Inventory equipment. List every machine and system that employees service, and identify every energy source on each, including stored energy.
2. Write equipment-specific procedures. Document shutdown, isolation points, device placement, stored energy release and verification for each machine.
3. Classify employees. Identify authorized, affected and other employees for each area.
4. Provide standardized devices. Issue individually keyed locks and compliant tags, and fit lockable isolating devices where possible.
5. Train and certify. Deliver role-based training, record names and dates, and schedule retraining triggers.
6. Inspect annually. Assign an independent authorized employee to observe each procedure in use and certify the inspection.
7. Coordinate contractors. Exchange procedures with outside servicing personnel before work begins.
8. Investigate and improve. Review incidents and near misses involving unexpected movement and update procedures accordingly.

How SMS360 Helps

The SMS360 Lockout Tagout module gives safety managers one place to keep equipment-specific energy control procedures, so authorized employees can pull up the right procedure on a mobile device at the machine. Digital checklists support the annual periodic inspection, and the record of who was inspected, when and by whom is stored with the procedure.

Training records and expiry reminders help keep authorized and affected employee training current, while corrective actions from inspections or incidents can be assigned and tracked to closure. Dashboards and stored records make it easier to show an auditor that the program works.

Frequently Asked Questions

Does the lockout/tagout standard apply to construction?

No. 29 CFR 1910.147 excludes construction and agriculture employment. Construction work involving hazardous energy is addressed by provisions in 29 CFR Part 1926, such as the electrical rules in Subpart K. Employers with both kinds of work should apply the correct standard to each activity.

How often do LOTO procedures need to be inspected?

Each energy control procedure must be inspected at least annually under 1910.147(c)(6). The inspector must be an authorized employee other than those using the procedure. The employer must certify each inspection with the equipment, date, employees included and inspector's name.

Can one procedure cover several machines?

Yes, if the machines are similar enough that the same steps, energy sources and isolation points apply. OSHA requires that procedures clearly and specifically outline the steps for the equipment involved. A single generic procedure that does not identify actual isolation points will usually fall short.

Is lockout/tagout training required every year?

The standard does not set a fixed annual retraining interval. Retraining is required when assignments, equipment, processes or procedures change, or when the annual inspection or other information shows deviations or inadequate knowledge.