Cord-and-Plug Equipment Exception to LOTO: Conditions and Limits

The cord and plug exception to lockout tagout, set out at 29 CFR 1910.147(a)(2)(iii)(A), lets an employer service cord-and-plug connected equipment without the full written procedures, hardware, and annual inspections the standard normally requires, but only when two conditions are both true at the same time: pulling the plug fully controls the hazard of unexpected startup, and the plug stays under the exclusive control of the worker doing the job.¹ Miss either condition and the exception disappears. The full standard then applies as if it had never been available, with penalties reaching $16,550 for a serious violation and $165,514 for a willful or repeated one.²

The Two Conditions in Plain Terms

The exception is narrow, and the regulation is written so that both parts must hold for the entire time servicing or maintenance is happening.¹

First, unplugging the cord must eliminate every source of hazardous energy the machine contains. If anything else could cause movement, shock, or release after the plug comes out, the first condition fails.

Second, the person doing the work must control the plug so completely that no one else can put it back in the receptacle. OSHA has spelled out what that looks like in practice, and the definition is stricter than most people assume.

If either condition breaks down at any point in the job, every requirement of the full LOTO standard applies retroactively to that work. There is no partial credit.

What Exclusive Control of the Plug Means

In an interpretation letter, OSHA identified three, and only three, ways a worker can maintain exclusive control:³

The plug is physically in the worker’s possession, held in the hand or kept on the person.
The plug is within the worker’s arm’s reach and in the worker’s line of sight. Both parts have to be true. Visible across the room does not count. Within reach but behind the worker does not count.
The plug is secured with a lockout device, meaning a cover or lock box that fits over the plug end, accepts a padlock, and physically prevents the plug from being reinserted into any receptacle.

That third option is the one most workplaces overlook. When the outlet sits around a corner, behind other equipment, or in a separate room, line-of-sight control is not possible. The worker either holds the plug through the entire job or uses a plug lockout device. Walking to a tool crib, turning a corner, or stepping into another room breaks exclusive control the moment it happens, and the exception stops applying at that moment, whether or not anyone actually touches the plug.

When Unplugging Alone Doesn’t Control the Hazard

The first condition fails more often than the second, because many machines with a standard plug still hold energy after the cord comes out of the wall. The regulation and its appendix identify capacitors, compressed springs, elevated components that could fall, rotating flywheels, and pressurized hydraulic or pneumatic systems as common sources of stored energy.⁴

A table saw whose blade coasts for 30 seconds after power loss still presents a hazard during that interval. A hydraulic press fed by both a cord and separate pneumatic lines has a second energy source the plug does not touch. Equipment with an internal battery backup or an uninterruptible power supply can re-energize itself after the cord is pulled, which makes the unplugging step meaningless as a safety measure.

Before relying on the exception, someone needs to walk through every energy source the machine contains and confirm that pulling the plug eliminates all of them. If the job requires a hydraulic bleed-down, a wait for a flywheel to stop, or a capacitor discharge step, those are signals that the full LOTO procedures apply instead.

Capacitors

Capacitors are an invisible hazard. The machine looks dead while the capacitor still holds enough charge to cause a serious shock or arc flash. Under a separate OSHA electrical standard, capacitors in equipment generally must include an automatic means of draining stored charge after disconnection from the power supply, although surge capacitors and capacitors that are components of other apparatus are exempt from that requirement.⁵ A working auto-drain supports use of the exception. A broken or missing one means unplugging does not control the electrical hazard.

Reaccumulation

Some equipment can rebuild dangerous energy levels after an initial bleed-down. The LOTO standard requires ongoing verification of isolation throughout the job when stored energy could reaccumulate to a hazardous level.⁴ Equipment with that characteristic almost certainly fails the cord-and-plug test, because the exception assumes unplugging provides complete protection without continued verification.

Only Servicing and Maintenance

The LOTO standard, and its exceptions, cover servicing and maintenance activities: installing, adjusting, inspecting, cleaning, unjamming, and making tool changes where a worker could be exposed to unexpected energization.¹ Normal production operation of the machine falls under different rules and is not governed by 1910.147 at all. A separate minor servicing provision exists for routine tasks integral to production, but it has its own requirements and is not the same as the cord-and-plug exception.⁴

Doing the Work Safely When the Exception Applies

When a machine genuinely qualifies, the process is short. Skipping the verification step is the shortcut that most often leads to injury.

Pull the plug from the receptacle. Don’t rely on the power switch. Switches fail, and a switch does not stop someone from turning it back on.
Secure exclusive control before starting. Keep the plug on your person, keep it within arm’s reach and in your line of sight, or attach a plug lockout device. Choose the method before beginning, not after realizing the outlet is around a corner.
Verify zero energy. Try to start the machine using its normal controls. It should not respond. This catches a second power source, an internal backup, or the wrong plug pulled.
Perform the work while maintaining exclusive control throughout. If you have to leave the area, take the plug or lock it out first.
Before reconnecting, check that tools and loose parts have been removed, guards are back in place, and no one is near moving components.
Plug the equipment back in and confirm normal operation.

The verification attempt takes seconds and catches the situations that hurt people: a forgotten secondary power source, a coworker who plugged a different machine into the same circuit, a cord pulled from the wrong outlet.

Inspecting the Cord and Plug Themselves

A separate standard requires visual inspection of cord-and-plug connected equipment before each use for obvious damage: loose parts, missing prongs, cuts in the outer jacket, or signs of internal damage like a crushed cord. Equipment with a defective cord or plug must be taken out of service until repaired.⁶ A frayed cord that exposes conductors can shock a worker even with the plug under exclusive control and the machine switched off, so this obligation runs alongside the LOTO analysis, not inside it.

Getting the Analysis Wrong

Employers who claim the exception when it does not actually apply face the same penalties as any other LOTO violation: up to $16,550 for a serious violation, up to $165,514 for willful or repeated violations.² A single inspection that finds multiple machines improperly relying on the exception can produce citations for each one.

Most problems are not deliberate. They come from employers who assume the exception covers any equipment with a plug, without checking energy sources or thinking through how exclusive control will actually be maintained. An inspector will look at whether the worker kept control of the plug, whether other energy sources existed, and whether the employer performed any assessment. Having a plug is not, by itself, a defense. The exception has two specific conditions, and the employer has to be able to show both were met. Documenting the energy source review, the exclusive control method chosen, and who did the assessment costs almost nothing next to the alternative.

1
Occupational Safety and Health Administration. 29 CFR 1910.147 – The Control of Hazardous Energy (Lockout/Tagout)
2
Occupational Safety and Health Administration. OSHA Penalties
3
Occupational Safety and Health Administration. Cord and Plug Connected Electric Equipment
4
eCFR. 29 CFR 1910.147 – The Control of Hazardous Energy (Lockout/Tagout)
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Occupational Safety and Health Administration. 29 CFR 1910.305 – Wiring Methods, Components, and Equipment for General Use
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eCFR. 29 CFR 1910.334 – Use of Equipment