OSHA Lockout/Tagout (29 CFR 1910.147): The Complete Compliance Guide

What Is OSHA Lockout/Tagout?

OSHA's Control of Hazardous Energy standard — commonly called lockout/tagout or LOTO — is found at 29 CFR 1910.147. It establishes requirements for controlling hazardous energy during the servicing and maintenance of machines and equipment. The standard protects workers from the unexpected energization or startup of machines, or the release of stored energy, which causes approximately 50,000 injuries and 120 fatalities in the United States each year.

LOTO is consistently one of OSHA's most cited standards. In fiscal year 2024, violations of 29 CFR 1910.147 ranked among the top ten most cited standards — reflecting both the standard's complexity and how frequently employers get it wrong.

Who Does OSHA 1910.147 Apply To?

The standard applies to general industry employers covered by OSHA 29 CFR 1910. It covers the servicing and maintenance of machines and equipment where the unexpected energization, startup, or release of stored energy could harm employees. This includes electrical energy, mechanical energy, hydraulic and pneumatic pressure, thermal energy, chemical energy, and gravitational energy.

Exceptions include: electrical work covered by OSHA's electrical standards (29 CFR 1910.331–335), work on cord- and plug-connected equipment where the plug is under exclusive control of the employee, hot tap operations on pressurized pipelines, and minor tool changes that don't expose workers to hazardous energy.

Construction industry employers follow 29 CFR 1926.417, which addresses similar hazards.

The Four Pillars of LOTO Compliance

1. Written Energy Control Program

The standard requires employers to develop, document, and use an energy control program. This written program must cover: the purpose and scope of the energy control procedures, rules and techniques for controlling hazardous energy, and means of enforcing compliance. The program is the foundation everything else builds on.

2. Energy Control Procedures (Machine-Specific)

For each piece of equipment that requires LOTO, employers must develop a documented procedure that identifies the steps to shut down, isolate, block, and secure hazardous energy. Each procedure must include:

• The specific steps to turn off and shut down the machine
• Steps to isolate the machine from each energy source
• Steps to lock or tag out the energy-isolating device
• Steps to release, restrain, or render safe any stored energy
• Steps to verify the machine is de-energized before work begins

OSHA allows a single procedure for groups of similar machines if the procedure fully applies to all of them — but in practice, machine-specific procedures are the safest approach.

3. Training

OSHA requires training for three categories of employees:

• Authorized employees — those who perform the LOTO procedures. Must be trained in recognition of hazardous energy sources, the type and magnitude of energy in the workplace, and the methods and means to isolate and control energy.
• Affected employees — those whose job requires them to operate equipment under LOTO or work in an area where LOTO is used. Must understand the purpose of the program and that they cannot restart or remove LOTO devices.
• Other employees — anyone else in the area. Must understand that they cannot restart or remove LOTO devices.

Retraining is required whenever there is reason to believe an employee doesn't understand the procedures, when procedures are changed, and when inspections reveal deficiencies. There is no fixed interval requirement — retraining is performance-based.

4. Annual Inspections

At least annually, employers must certify that an inspection was performed on each energy control procedure. The inspection must be performed by an authorized employee other than the one using the procedure. The inspection must certify that the procedure is adequate and the employee is following it. The certification must include the machine or equipment name, the date of inspection, the employees included, and the name of the inspector.

The LOTO Sequence: Step by Step

Authorized employees follow a sequence of steps to safely apply LOTO before beginning maintenance work:

1. Prepare for shutdown. Identify all energy sources — electrical, mechanical, hydraulic, pneumatic, thermal, chemical, gravitational. Gather the required locks, tags, hasps, and other hardware.
2. Notify affected employees. Inform all affected employees that the machine will be shut down and LOTO applied.
3. Shut down the machine. Follow the normal stopping procedure.
4. Isolate all energy sources. Operate each energy-isolating device (circuit breakers, valves, blocks) to cut off all energy to the machine.
5. Apply LOTO devices. Lock or tag out each energy-isolating device. Each authorized employee applies their personal lock — one employee, one lock, one key.
6. Release or restrain stored energy. Discharge capacitors, bleed hydraulic pressure, release spring tension, block gravity-driven parts. Stored energy must be controlled, not just the source.
7. Verify de-energization. Before touching the machine, verify that it is isolated and de-energized. Try to start it. Check for residual energy with appropriate test equipment.

To restore energy after work is complete, reverse the process: remove tools and materials, ensure all employees are clear, remove personal LOTO devices, restore energy-isolating devices, and notify affected employees.

Lockout vs. Tagout: When to Use Each

Lockout is always preferred. A lock physically prevents a device from being operated. A tag is only a warning — it can be removed or ignored. OSHA requires lockout whenever the energy-isolating device is capable of being locked. Tagout is only permissible when lockout is not feasible — and even then, the employer must demonstrate that the tagout program provides equivalent protection to lockout.

Tagout systems require additional protective measures to compensate for the reduced level of protection: removing isolation circuit elements, blocking control switches, opening extra disconnects, removing valve handles.

Group LOTO Procedures

When multiple authorized employees work on the same machine, each must apply their personal lock to the energy-isolating device or to a group lockout hasp. Group procedures must afford each employee a level of protection equivalent to having their own personal lock. A group box procedure — where one person holds a key to the group box and all others lock the box — is a common approach, but must be managed carefully to ensure each employee's lock stays applied until their work is complete.

Contractor LOTO

When outside contractors perform maintenance on equipment, the host employer and the contractor must inform each other of their respective LOTO procedures and ensure that each understands and complies with the other's restrictions. This coordination requirement is frequently overlooked and frequently cited in OSHA inspections involving contractors.

Common LOTO Violations and How to Avoid Them

• No written program. Every covered employer must have one. This is a paperwork violation that's easy to fix — and easy for an inspector to cite.
• Missing machine-specific procedures. Generic LOTO procedures aren't sufficient for complex equipment. Identify every machine requiring LOTO and document a procedure for each.
• Inadequate training records. Training must be documented. If you can't show it was done, for OSHA purposes, it wasn't done.
• Skipping annual inspections. The annual certification requirement is frequently overlooked. Set a calendar reminder and document the inspection properly.
• Not controlling stored energy. Electrical lockout gets attention; hydraulic pressure, spring tension, and elevated machine components get less. All stored energy must be addressed.
• Contractor coordination failures. When contractors work on your equipment, the coordination requirement applies. Document it.

How AI Automates LOTO Compliance — Without Adding Headcount

The administrative burden of a compliant LOTO program is significant: maintaining training records for every authorized and affected employee, scheduling and documenting annual procedure inspections, tracking when retraining is triggered by procedure changes or inspection findings, and producing those records on demand during an OSHA inspection. In most organizations, this falls on a single safety manager who has forty other things to track simultaneously.

Gerty handles the parts that don't require human judgment:

• Training delivery — automated. Gerty generates OSHA-aligned LOTO training content calibrated to each employee's role (authorized vs. affected vs. other), delivers it to their inbox on schedule, and logs completion — without any manual tracking or reminder emails from the safety manager.
• Retraining triggers — monitored. When procedure changes or inspection findings require retraining, Gerty requeues the affected employees automatically. No spreadsheet update required.
• Completion reporting — weekly. Every Friday, Gerty emails the safety manager a compliance report showing who has completed LOTO training, who is overdue, and what the current completion rate is by employee group.
• Documentation — always current. Training records are maintained in Gerty's system and available for export during an OSHA inspection — no scrambling to reconstruct records from email threads and sign-in sheets.

What Gerty does not replace: the qualified person who writes machine-specific LOTO procedures, conducts the annual certification inspection, and makes engineering judgments about energy isolation. Those remain human functions. Gerty removes the administrative overhead around them so the safety manager's time goes to the work that actually requires expertise.

Start a free Gerty trial — 1 organization, up to 5 employees, no credit card required. Your LOTO training runs automatically from day one.