Tag controls, secure every energizing point, place one lock per person, verify the circuit is dead, and write the procedure before repair starts.
Key takeaways for what to lock and tag before repairing a jobsite circuit
- Tag the deactivated control. Controls that are to be deactivated during work on energized or deenergized equipment or circuits shall be tagged, according to Legal Information Institute.
- Tag every energizing point. Equipment or circuits that are deenergized shall be rendered inoperative and shall have tags attached at all points where such equipment or circuits can be energized, according to Legal Information Institute.
- Apply one lock per person. If a maintenance job requires 3 workers, then 3 locks should be present, and each individual must place their own lock on the system, according to CCOHS.
- Verify deenergization with test equipment. A qualified person must use test equipment to test the circuit elements and electrical parts of equipment to which employees will be exposed and must verify that the circuit elements and equipment parts are deenergized, according to Washington State Legislature.
- Document the procedure in writing. The employer's hazardous energy control procedures shall be documented in writing, according to California Department of Industrial Relations.
Before the repair starts, tag the control that will be deactivated, according to Legal Information Institute.
What to lock, tag, and test before a circuit repair starts
The same source requires that equipment or circuits that are deenergized shall be rendered inoperative and shall have tags attached at all points where such equipment or circuits can be energized, according to Legal Information Institute. This covers the second check, ensuring no alternate power source or bypass can restart the circuit while work is underway.
Lockout is defined in the Canadian standard CSA Z460-20 "Control of Hazardous Energy - Lockout and Other Methods" as the "placement of a lockout device on an energy-isolating device in accordance with an established procedure," according to CCOHS. A lockout device is "a mechanical means of locking that uses an individually keyed lock to secure an energy-isolating device in a position that prevents energization of a machine, equipment, or a process," according to CCOHS.
The fifth check is documentation. The employer's hazardous energy control procedures shall be documented in writing, according to California Department of Industrial Relations. This written procedure ensures the steps are consistent and available for review before the work begins. For the day's written record, see Construction Daily Log Checklist for Supervisors.
Which controls and disconnects each page says to tag or lock
The first two checks focus on identifying the specific points where the circuit can be energized and securing them.
Tag the deactivated control
According to Legal Information Institute, controls that are to be deactivated during the course of work on energized or deenergized equipment or circuits shall be tagged. This requirement applies specifically to the controls being deactivated. The tag must identify plainly the equipment or circuits being worked on, as stated in the same source. If you are working in Washington, the rule is more specific about the method. According to Washington State Legislature, you must tag and padlock controls that are deactivated during the course of work on energized or deenergized equipment or circuits in the open position. This means the control must be in the open position when you apply the tag and padlock.
Tag and lock every energizing point
It is not enough to tag just the main switch. You must secure every point where the circuit can be energized. According to Legal Information Institute, equipment or circuits that are deenergized shall be rendered inoperative and shall have tags attached at all points where such equipment or circuits can be energized. This ensures that no one can accidentally restore power from a secondary source. In Washington, the requirement includes both tags and locks. According to Washington State Legislature, you must render equipment or circuits that are deenergized inoperative and attach tags and locked padlocks at all points where such equipment or circuits can be energized. This dual requirement of tags and locked padlocks at all energizing points is a specific Washington State standard.
What is not a valid deenergizing method
A common mistake is relying on a push button or interlock to keep the circuit dead. This is not a valid lockout method. According to Washington State Legislature, you must not use control circuit devices, such as push buttons, selector switches, and interlocks, as the sole means for deenergizing circuits or equipment.
Practical steps for your site
- Identify the main disconnect for the circuit you are repairing.
- Open the disconnect to the open position.
- Apply a tag to the control that identifies the equipment or circuit being worked on.
- Apply a padlock to the control in the open position when Washington requirements apply.
- Identify any other points where the circuit could be energized, such as secondary sources or bypass switches.
- Render the circuit inoperative and attach tags at all these other points, and attach locked padlocks there only under the Washington rule.
- Verify that you are not relying on a push button, selector switch, or interlock as the sole means of deenergization.
By following these steps, you ensure that the circuit is properly tagged and locked at every possible energizing point. This is the foundation for the subsequent checks of verifying the circuit is dead and documenting the procedure. If the same crew later welds, see Hot-work handoff: 6 checks before the crew welds for a separate pre-start list.
Who may remove a lock, and how many locks go on the system
The CCOHS page defines lockout as the placement of a lockout device on an energy-isolating device in accordance with an established procedure, where the device is a mechanical means of locking that uses an individually keyed lock to secure the isolating device in a position that prevents energization of a machine, equipment, or a process CCOHS. This definition establishes the physical requirement for the lock itself before addressing who applies it.
For example, if a maintenance job requires 3 workers, then 3 locks should be present – each individual must place their OWN lock on the system CCOHS.
The removal of these locks is strictly limited. ONLY the authorized individual who placed the lock and tag onto the system is the one who is permitted to remove them CCOHS. No other person, including a supervisor, foreman, or coworker, may remove a lock that was placed by someone else.
To enforce this individual accountability, each lock should only have one key (no master keys are allowed) CCOHS. A master key system would allow any person with that key to open any lock, which violates the requirement that only the lock owner can remove their specific device.
The tag associated with the lock must also record specific information. The tag should include the time and date of application of the lock/tag CCOHS. This timestamp provides a record of when the isolation was established, which is useful for tracking the duration of the lockout and for verifying that the procedure was followed at the correct time.
A filled reference table of each publisher's lockout rule
The table below lists the specific lockout or tagging rule from each of the four supplied sources. Each row names the publisher and quotes the exact requirement from that source.
| Publisher | Rule or Definition | Source Quote |
|---|---|---|
| Legal Information Institute | Controls to be deactivated during work on energized or deenergized equipment or circuits shall be tagged. | "Controls that are to be deactivated during the course of work on energized or deenergized equipment or circuits shall be tagged." |
| CCOHS | Lockout is the placement of a lockout device on an energy-isolating device in accordance with an established procedure. | "Lockout is defined in the Canadian standard CSA Z460-20 \"Control of Hazardous Energy - Lockout and Other Methods\" as the \"placement of a lockout device on an energy-isolating device in accordance with an established procedure.\" A lockout device is \"a mechanical means of locking that uses an individually keyed lock to secure an energy-isolating device in a position that prevents energization of a machine, equipment, or a process.\"" |
| California Department of Industrial Relations | Tagout device attachment means shall be non-reusable, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of no less than 50 pounds. | "Tagout device attachment means shall be of a non-reusable type, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of no less than 50 pounds." |
| Washington State Legislature | Controls deactivated during work on energized or deenergized equipment or circuits must be tagged and padlocked in the open position. | "You must tag and padlock controls that are deactivated during the course of work on energized or deenergized equipment or circuits in the open position." |
The Legal Information Institute entry cites 29 CFR § 1926.417 regarding the tagging of controls according to Legal Information Institute. The CCOHS entry defines lockout in the Canadian standard CSA Z460-20 according to CCOHS. The California Department of Industrial Relations entry specifies the physical strength requirements for tagout attachments under Title 8, Section 3314 according to California Department of Industrial Relations. The Washington State Legislature entry requires both tagging and padlocking for deactivated controls according to Washington State Legislature.
How the page says to prove the circuit is deenergized
Check 4 requires a qualified person to use test equipment to verify the circuit is dead before anyone touches the equipment. The Washington State Legislature specifies that this qualified person must test the circuit elements and electrical parts of equipment to which employees will be exposed. The goal is to verify that these circuit elements and equipment parts are deenergized, according to Washington State Legislature. This is not a visual check or a guess based on the disconnect handle position. It is an active measurement using the proper tool.
The rule adds a specific requirement for high-voltage circuits. If the circuit to be tested is over 600 volts, nominal, the test equipment must be checked for proper operation immediately before and immediately after this test, according to Washington State Legislature. You must check the instrument’s operation right before the test and again right after it. For circuits at or below 600 volts, the text does not mandate this specific pre- and post-test instrument check in the same way, but the requirement to use test equipment to verify deenergization remains.
Do not assume a push button or interlock is enough to deenergize the circuit. The rule focuses on the result: the parts must be verified as deenergized. If the test shows voltage, the circuit is not ready. Stop. Do not proceed with the repair. The qualified person is the one responsible for this verification. If you are not the qualified person, you are waiting for the result. You are not touching the equipment until that person confirms the test passed.
For the supervisor, this step is the gate between "we locked it out" and "it is safe to work." The lock keeps the disconnect open. The test proves the disconnect actually stopped the power. One without the other is incomplete. The lock prevents accidental re-energization. The test confirms the deenergization is real. Both are required by the rule.
Illustrative example of three locks on one repair
This walk-through uses round numbers only and names no crew or machine.
Three people are on the repair. Three locks go on the system, and each person places one lock. Each lock has one key. The control is opened and tagged before work. A qualified person tests the circuit elements. The circuit in this example is over 600 volts, nominal, so the test equipment is checked immediately before the test and immediately after it. The tag records the time and date the lock was applied. The written procedure is already on paper. Only the person who placed a lock removes that lock. If the test shows the parts are not deenergized, the repair waits.
Blank lines for the circuit, lock owner, and test result
The fifth check requires that the hazardous energy control procedures be documented in writing. This written requirement applies specifically to the cleaning, repairing, servicing, setting-up, and adjusting of machines and equipment where unexpected energization, start-up, or release of stored energy could cause injury to employees. The rule is found in California Code of Regulations, Title 8, Section 3314. This section covers the control of hazardous energy for prime movers, machinery, and equipment, including lockout and tagout operations.
For a small-firm supervisor, the written procedure is not just a file in a binder; it is the record that proves the specific steps were followed for the specific circuit being repaired. The procedure must match the actual work being performed. If the work involves repairing a machine where unexpected energization could cause injury, the written steps must reflect that specific hazard. The documentation serves as the baseline for the lockout and tagout actions taken by the crew. It ensures that the control measures are consistent and that the team knows exactly what is required to isolate the energy source before work begins. For a permit-style record of entry checks, see Confined space entry records: 6 permit checks.
| Line | What to write |
|---|---|
| Example | the circuit being repaired, the person who placed the lock, and whether the test showed the parts deenergized |
Fill those lines before work starts
Today, fill the blank lines for this circuit, the lock owner, and the test result, and set that sheet with the written procedure before anyone touches the equipment.
FAQ about locking out a jobsite circuit
What does the federal page say to attach to a deenergized circuit?
The federal regulation requires that tags be placed to identify plainly the equipment or circuits being worked on. These tags must be attached at all points where such equipment or circuits can be energized, according to Legal Information Institute. This requirement ensures that the specific circuit is clearly marked for anyone approaching the work area.
How many locks does the Canadian page call for when three people work on the job?
If a maintenance job requires three workers, then three locks should be present on the system. Each individual must place their own lock on the system, according to CCOHS. This rule ensures that every worker has a personal barrier preventing the circuit from being re-energized.
Who may remove a lock on the Canadian page?
Only the authorized individual who placed the lock and tag onto the system is the one who is permitted to remove them, according to CCOHS. No other person may remove the lock or tag from the system. This restriction keeps the removal process tied strictly to the person who applied the safety device.
When does the Washington page require the test instrument to be checked before and after the test?
This check applies specifically to circuits exceeding the 600-volt nominal threshold. The verification happens right before the test and right after it is completed.
What strength does the California page give for a tagout attachment?
Tagout device attachment means shall be of a non-reusable type, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of no less than 50 pounds, according to California Department of Industrial Relations. The attachment must meet this specific strength requirement to be considered compliant. This standard defines the physical durability needed for the tagout device on the equipment.