Lockout/Tagout: Controlling Hazardous Energy

A machine that starts up, or releases stored energy, while someone is servicing it can injure that person. OSHA's lockout/tagout standard requires you to set up a program and use procedures for putting lockout or tagout devices on energy isolating devices, and otherwise disabling machines, to prevent that (1910.147(a)(3)(i)).

Who it applies to

The standard covers servicing and maintenance of machines and equipment where unexpected energization, start up, or release of stored energy could injure employees (1910.147(a)(1)(i)). That includes setting up, adjusting, inspecting, lubricating, cleaning, and unjamming (1910.147(b)).

It does not cover (1910.147(a)(1)(ii)):

• Construction and agriculture employment
• Employment covered by 29 CFR parts 1915, 1917, and 1918
• Installations under the exclusive control of electric utilities for power generation, transmission, and distribution
• Electrical hazards in electric-utilization installations covered by Subpart S
• Oil and gas well drilling and servicing

Normal production operations are not covered. Servicing during production is covered only if an employee must remove or bypass a guard or other safety device, or place any part of the body in the point of operation or an associated danger zone during a machine operating cycle (1910.147(a)(2)(ii)). Even then, minor tool changes, adjustments, and other minor servicing are not covered if they are routine, repetitive, and integral to production, provided alternative measures give effective protection (Exception to 1910.147(a)(2)(ii)).

Also excluded: cord and plug connected electric equipment when unplugging controls the hazard and the plug is under the exclusive control of the employee doing the work (1910.147(a)(2)(iii)(A)), and hot tap operations on pressurized pipelines if you demonstrate the listed conditions (1910.147(a)(2)(iii)(B)).

What the standard requires

An energy control program

You must establish a program of energy control procedures, employee training, and periodic inspections, so that machines are isolated from the energy source and rendered inoperative before anyone services them (1910.147(c)(1)).

Lockout versus tagout

• If an energy isolating device cannot be locked out, your program must use tagout (1910.147(c)(2)(i)).
• If it can be locked out, you must use lockout, unless you can demonstrate that tagout will provide full employee protection (1910.147(c)(2)(ii)).
• To use tagout on a lockable device, you must attach the tag where the lock would have gone and demonstrate safety equivalent to lockout (1910.147(c)(3)(i)).

Energy control procedures

Procedures must be developed, documented, and used (1910.147(c)(4)(i)). They must clearly and specifically outline the scope, purpose, authorization, rules, techniques, and means to enforce compliance, including specific steps for shutting down, isolating, blocking, and securing machines, for placing, removing, and transferring devices, and for testing the controls (1910.147(c)(4)(ii)).

Locks, tags, and hardware

You must provide the locks, tags, and other hardware (1910.147(c)(5)(i)). Lockout and tagout devices must be singularly identified, be the only devices used for controlling energy, and not be used for other purposes (1910.147(c)(5)(ii)). They must also be:

• Able to withstand the environment they are exposed to (1910.147(c)(5)(ii)(A)(1))
• Standardized within the facility by color, shape, or size, and for tags, in print and format (1910.147(c)(5)(ii)(B))
• Substantial. Locks must prevent removal without excessive force or unusual techniques. Tag attachments must be non-reusable, attachable by hand, self-locking, and non-releasable, with an unlocking strength of no less than 50 pounds (1910.147(c)(5)(ii)(C)(1) and (C)(2))
• Marked to identify the employee who applied them (1910.147(c)(5)(ii)(D))

Tags must warn against hazardous conditions with a legend such as "Do Not Start" or "Do Not Operate" (1910.147(c)(5)(iii)).

Applying the controls

Your procedures must cover these steps, in this sequence (1910.147(d)):

1. The authorized employee knows the type and magnitude of the energy, its hazards, and how to control it (1910.147(d)(1)).
2. Shut the machine down in an orderly way (1910.147(d)(2)).
3. Locate and operate every energy isolating device needed (1910.147(d)(3)).
4. Authorized employees affix a lock or tag to each energy isolating device (1910.147(d)(4)(i)).
5. Relieve, disconnect, restrain, and otherwise render safe all potentially hazardous stored or residual energy (1910.147(d)(5)(i)).
6. Before starting work, the authorized employee verifies isolation and deenergization (1910.147(d)(6)).

Release from lockout or tagout

Before devices come off, authorized employees must inspect the work area to make sure nonessential items are removed and components are operationally intact (1910.147(e)(1)), and check that all employees are safely positioned or removed (1910.147(e)(2)(i)). Each device must be removed by the employee who applied it (1910.147(e)(3)), subject to one exception described under Easy-to-miss requirements below.

Groups, shift changes, and contractors

• Group work must use a procedure giving protection equivalent to a personal lock or tag (1910.147(f)(3)(i)). Each authorized employee must affix a personal device to the group lockout device, lockbox, or comparable mechanism when starting work and remove it when stopping (1910.147(f)(3)(ii)(D)).
• Specific procedures must be used at shift or personnel changes, including orderly transfer of protection between off-going and oncoming employees (1910.147(f)(4)).
• Whenever outside servicing personnel will do work covered by this standard, you and the outside employer must inform each other of your respective lockout or tagout procedures (1910.147(f)(2)(i)). You must ensure your employees understand and comply with the outside employer's restrictions and prohibitions (1910.147(f)(2)(ii)).

Periodic inspection

You must conduct a periodic inspection of the energy control procedure at least annually to ensure that the procedure and the requirements of the standard are being followed (1910.147(c)(6)(i)). The inspection must include a review of responsibilities with each authorized employee and, where tagout is used, each affected employee (1910.147(c)(6)(i)(C) and (D)).

Training

You must provide training (1910.147(c)(7)(i)):

• Authorized employees: recognizing hazardous energy sources, the type and magnitude of energy in the workplace, and the methods of isolation and control (1910.147(c)(7)(i)(A)).
• Affected employees: the purpose and use of the procedure (1910.147(c)(7)(i)(B)).
• All other employees working where procedures may be used: the procedure and the prohibition on restarting locked or tagged equipment (1910.147(c)(7)(i)(C)).

Where tagout is used, employees must also be trained on the limitations of tags (1910.147(c)(7)(ii)).

Authorized and affected employees must be retrained when job assignments change, when a change in machines, equipment, or processes presents a new hazard, or when procedures change (1910.147(c)(7)(iii)(A)). Retraining is also required when a periodic inspection reveals, or you have reason to believe, that an employee's knowledge or use of the procedures falls short (1910.147(c)(7)(iii)(B)).

Written programs and records

• Documented procedures (1910.147(c)(4)(i)). You need not document the procedure for a machine when all eight listed conditions exist, including a single energy source and no potential for stored energy (Exception to 1910.147(c)(4)(i)).
• Inspection certification identifying the machine, the inspection date, the employees included, and the inspector (1910.147(c)(6)(ii)).
• Training certification with each employee's name and dates of training (1910.147(c)(7)(iv)).

Neither certification paragraph states a retention period.

Easy-to-miss requirements

• The periodic inspection must be performed by an authorized employee other than the one(s) using the procedure being inspected (1910.147(c)(6)(i)(A)).
• When machines are replaced, newly installed, or undergo major repair, renovation, or modification after January 2, 1990, their energy isolating devices must be designed to accept a lockout device (1910.147(c)(2)(iii)).
• Affected employees must be notified before controls are applied and after they are removed (1910.147(c)(9)).
• When the employee who applied a device is not available, it may be removed under your direction only if specific procedures and training for that removal are developed, documented, and built into your program. You must demonstrate that the procedure provides safety equivalent to removal by the employee who applied the device. At a minimum the procedure must include verifying that the employee is not at the facility, making all reasonable efforts to contact the employee to tell them the device has been removed, and ensuring the employee knows this before resuming work at the facility (Exception to 1910.147(e)(3)).

Related guides

• Machine guarding
• Electrical safety
• Confined spaces

Source

This guide is based on the text of 29 CFR 1910.147 as published on osha.gov. The regulation itself always controls. States that run their own OSHA-approved State Plans may have additional or stricter rules.