OSHA 29 CFR 1910.147 — the Control of Hazardous Energy standard, commonly called the "Lockout/Tagout standard" — requires employers to establish a program and procedures that disable machinery and prevent the release of hazardous energy while employees perform servicing and maintenance. It is one of the most-cited safety standards in the world and the foundation of every LOTO program.
What the standard covers
1910.147 applies to the servicing and maintenance of machines and equipment where the unexpected start-up, energisation, or release of stored energy could harm an employee. It covers all forms of hazardous energy: electrical, mechanical, hydraulic, pneumatic, chemical, thermal, and gravitational.
The three parts of an energy control program
OSHA requires a documented energy control program built on three elements:
- Energy control procedures — written, equipment-specific steps for shutting down, isolating, locking, and verifying each machine.
- Employee training — so every worker understands the program and their role in it.
- Periodic inspection — at least annually, to confirm procedures are being followed correctly.
Lockout is preferred over tagout
OSHA requires lockout (a physical lock) wherever an energy-isolating device can accept one. Tagout (a warning tag alone) is permitted only when a device cannot be locked, and it must provide full employee protection. Whenever equipment is replaced or upgraded, it must be capable of being locked out.
Requirements for lockout devices
Under 1910.147(c)(5), lockout devices must be:
- Durable — able to withstand the environment for the maximum exposure period.
- Standardised — uniform in colour, shape, or size across the facility.
- Substantial — strong enough to prevent removal without excessive force or tools.
- Identifiable — clearly indicating the identity of the worker who applied them.
This is why a compliant program uses dedicated safety padlocks, hasps, and danger tags rather than improvised hardware.
The required isolation sequence
For each machine, authorised employees follow a defined sequence: prepare for shutdown, shut down, isolate every energy source, apply lockout/tagout devices, release stored or residual energy, and verify isolation before work begins. See our guide on what lockout/tagout is for the full step-by-step.
Periodic inspection and training
The program must be inspected at least annually by an authorised employee who is not using the procedure being inspected, and any deviations corrected. Authorised, affected, and other employees must be trained on the program and retrained whenever procedures or job assignments change.
How we help you comply
As the authorised distributor of LOTO Safety Products in Uzbekistan, we supply standardised, durable lockout devices that meet 1910.147's requirements, and we run free on-site LOTO assessments to help you map energy sources and build compliant procedures. Contact our team to get started.