The short answer: Electrical work should be done deenergized. 29 CFR 1910.333(a)(1) requires deenergizing exposed live parts before work unless the employer can show deenergizing adds hazard or is infeasible. When work must be energized, NFPA 70E requires an energized electrical work permit (EEWP) that documents the justification, the shock and arc-flash risk assessments, the safe work practices, and management approval. To create the deenergized state, 1910.333(b) requires locking and tagging the disconnecting means, releasing stored energy, and having a qualified person verify the absence of voltage with test equipment before touching the parts. NFPA 70E is a consensus standard; the lockout duty for electrical work sits in OSHA's Subpart S, not in the general lockout rule 1910.147.
When is energized electrical work actually allowed?
Only when deenergizing would create a greater hazard or is genuinely infeasible, and never merely because it is faster or cheaper. 29 CFR 1910.333(a)(1) makes deenergizing the rule and allows energized work only where "deenergizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations." Additional hazards means things like interrupting life-support ventilation, emergency alarms, or hazardous-location ventilation; infeasibility means the equipment genuinely cannot be shut down for the task, not that shutting it down is disruptive.
Most energized work fails that test. Diagnostic tasks such as testing and troubleshooting have to be done with the circuit live by their nature, and NFPA 70E treats those specific tasks differently, but replacing a component, landing a wire, or servicing a fixture almost always can be done deenergized with planning. The first control is therefore a habit of asking whether the task truly requires energized parts, because the answer reframes the entire job from a permit-and-PPE problem into a lockout problem.
What is an energized electrical work permit and what must it contain?
An energized electrical work permit is the document that authorizes justified energized work and records the controls, and NFPA 70E in Article 130 requires it whenever a worker crosses the restricted approach boundary or interacts with equipment in a way that raises the likelihood of an arc flash. It is the gate that forces the decision to be deliberate and approved rather than made alone at the panel.
NFPA 70E specifies the permit's minimum elements. In practice they include a description of the circuit and equipment and its location; a description of the work; the justification for why it must be done energized; the safe work practices to be used; the results of the shock risk assessment and the arc-flash risk assessment, including the boundaries and the incident energy or PPE category and the required PPE; the means to restrict unqualified persons from the area; evidence that a job briefing was completed; and the approval signatures of authorizing management. NFPA 70E also exempts a defined set of tasks from needing a signed permit, notably testing, troubleshooting, and voltage measurement, and certain inspections, when performed by qualified persons using appropriate safe work practices and PPE. The permit is not a formality: the justification and sign-off lines are where an organization decides, on the record, that this specific energized task is warranted.
The shock risk assessment on that permit turns on the approach boundaries, and they are worth understanding because they govern who may get how close. NFPA 70E defines a limited approach boundary, which an unqualified person may not cross without a qualified escort, and a closer restricted approach boundary, which only a qualified person using shock protection may cross because of the increased risk of contact. The energized electrical work permit is triggered when work crosses that restricted approach boundary, so the boundaries are not abstract lines: they decide, for a given voltage, the distance at which the permit, the qualification, and the shock PPE all become mandatory. A program that marks those boundaries in the field, rather than leaving them on paper, gives the crew a physical cue for when they have moved from observing to performing energized work.
How do you lock out and verify an electrical circuit?
Disconnect every source, lock and tag the disconnecting means, release stored energy, and then have a qualified person prove the circuit is dead with a tester before anyone touches it. 29 CFR 1910.333(b)(2) sets this sequence for electrical work: the circuit is disconnected from all electric energy sources, control-circuit devices alone are not accepted as the means of deenergizing, stored energy in capacitors is discharged and high-capacitance elements are grounded where the stored charge could endanger someone, and a lock and a tag are placed on each disconnecting means. Crucially, 1910.333(b)(2)(iv)(B) requires a qualified person to use test equipment to verify that the circuit elements and equipment parts are deenergized, and to confirm the test instrument works before and after the test.
The verification test is the step that most often decides whether the lockout was real, because it is the only point where the theory that "the power is off" gets tested against the actual conductor. A locked disconnect, a tag, and a mental model of the circuit are all assumptions until an instrument confirms zero voltage at the point of work. The requirement to check the tester before and after the reading exists precisely because a meter that has failed can display a reassuring zero on a live conductor, and that false-dead reading is one of the ways experienced workers are killed on circuits they believed were safe.
One point of law often causes confusion. The general lockout/tagout standard, 29 CFR 1910.147, explicitly does not cover exposure to electrical hazards from work on electric utilization installations, which its scope assigns to Subpart S. So the lockout requirements for working on an electrical circuit come from 1910.333(b), while 1910.147 governs lockout of the hazardous energy in machines and equipment being serviced. The two overlap in practice, and a facility's lockout program should address both, but for the electrical hazard itself the controlling text is Subpart S, and its non-negotiable step is the verification test.
What happens when the lockout is only partial?
A single missed source turns a supposedly dead circuit into a fatal one, which is exactly what a New Jersey investigation documented. In NJ FACE report 95-NJ-080-01, a 36-year-old electrician's helper, on the job twelve days, was replacing 460-volt fluorescent fixtures and ballasts in a department store fitting room. The foreman shut off and locked out the wall switch and checked the lights with a tester, but one center fixture was on a separate night-light circuit and stayed energized. Unable to find the breaker for it, the foreman asked the helper if he had worked live wires before and told him to go ahead. The helper cut the energized 460-volt wire with an insulated trimmer, his other hand contacted the metal cutter, and the current passed through him to the grounded metal door frame he was leaning against. He died of cardiac arrhythmia due to electrocution. NJDOH FACE found the company had a written lockout/tagout program and lockout devices on site, but the procedures were not fully followed, and noted that lockout/tagout is required under 29 CFR 1910.333. The transferable lesson is that partial deenergization is not deenergization: the lockout has to reach every source, and the verification test on each part is what would have caught the live circuit before the cut.
Who is allowed to do this work?
Only a qualified person, and being told to "go ahead" is not qualification. 29 CFR 1910.333(c)(2) permits only qualified persons to work on circuit parts that have not been deenergized, and 1910.332(b)(3) defines the qualified person as one trained to identify exposed energized parts, determine their nominal voltage, and observe the required clearance distances. In the New Jersey case, investigators concluded the helper did not have the training or experience to work on energized circuits, and recommended that only specifically trained employees do energized work, and only when it is unavoidable, with the necessary PPE. That maps directly onto the program controls: the permit forces the justification, the qualification requirement decides who may hold it, and the verified lockout is what makes deenergized work the safer path the standard intends it to be.
