4.1 The rule, and the only two exceptions

1 The rule

1910.333(a)(1): "Live parts to which an employee may be exposed shall be deenergized before the employee works on or near them, unless the employer can demonstrate that deenergizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations."

Four things in that sentence deserve attention. Shall be deenergized — not "should", and not "where practical". On or near them — the duty is not limited to touching. The employer can demonstrate — the burden sits with the employer, not with the worker, and demonstrating means being able to show it, which in practice means writing it down. Two grounds, and only two.

2 Ground one: deenergizing would introduce additional or increased hazards

Note 1 to 1910.333(a)(1) gives OSHA's own examples of hazards that shutting down would create: "interruption of life support equipment, deactivation of emergency alarm systems, shutdown of hazardous location ventilation equipment, or removal of illumination for an area."

Look at what those have in common. Each one is a safety system that other people depend on right now. Losing the ventilation in a classified area, losing the alarm in an occupied building, losing the lights in a space people are working in — the shutdown moves the hazard onto someone else rather than removing it.

What is not on that list: production, schedule, cost, inconvenience, a tenant who does not want the outage, and a customer who will be annoyed. Those are real business problems, and none of them is an additional or increased hazard.

3 Ground two: infeasible due to equipment design or operational limitations

Note 2 gives the examples: "Examples of work that may be performed on or near energized circuit parts because of infeasibility due to equipment design or operational limitations include testing of electric circuits that can only be performed with the circuit energized and work on circuits that form an integral part of a continuous industrial process in a chemical plant that would otherwise need to be completely shut down in order to permit work on one circuit or piece of equipment."

The first example is the honest one everybody uses: you cannot measure a live voltage on a dead circuit. Troubleshooting genuinely requires energization, and that is why the great majority of legitimate energized work permits are for testing and diagnostics rather than for repair. The second is narrower than it is usually claimed to be — an integral part of a continuous process where the alternative is a complete plant shutdown, not merely an inconvenient one.

4 The 50-volt exception, and what it is not

The same paragraph carries an exception: live parts that operate at less than 50 volts to ground need not be deenergized "if there will be no increased exposure to electrical burns or to explosion due to electric arcs."

Both halves apply. Under 50 volts to ground and no increased burn or arc exposure. A low-voltage control circuit inside a cabinet full of 480-volt terminals fails the second half, because the exposure is not to the control circuit — it is to what surrounds it. And Part 1 of this course gave the physiological caution: OSHA 3075 states that longer exposures at relatively low voltages can be as dangerous as short exposures at higher voltages, and that low voltage does not imply low hazard.

5 If it stays energized, what changes

1910.333(a)(2): where live parts are not deenergized for one of those reasons, "other safety-related work practices shall be used to protect employees who may be exposed to the electrical hazards involved." The practices must be suitable for the conditions and for the voltage level, and they must "protect employees against contact with energized circuit parts directly with any part of their body or indirectly through some other conductive object."

Directly and indirectly. That second word is why the tools, the ladder rails, the ropes and the jewelry all get their own paragraphs in (c)(6) through (c)(9), and why Chapter 3 of this part goes through them one by one.

And 1910.333(c)(2) then closes the population: only qualified persons may work on parts that have not been deenergized, and such persons "shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools."

6 The permit, and where it actually comes from

There is no paragraph in 29 CFR called "energized electrical work permit". The document exists because 1910.333(a)(1) places a burden of demonstration on the employer, and a written permit is the ordinary way to carry a burden of demonstration. The practice itself — the form, the fields, the signatures — comes from NFPA 70E, a private consensus standard that OSHA references in guidance but does not publish and that is copyrighted. This course does not reproduce it.

What a CFR-based permit records is straightforward: which ground applies, the specific hazard or limitation behind it, what was considered to allow a shutdown and why it was rejected, the work practices verified on site, who is qualified for this equipment, the emergency arrangements, and the signatures — before the work, and again when the equipment is back to normal.

7 Reading a justification, line by line

The employer carries the burden of demonstration, but the person doing the work is usually the first reader of the justification. Four tests separate a real one from a comfortable one, and they take about a minute.

That last row is where most legitimate energized work goes wrong. Diagnostics genuinely require an energized circuit; replacing the component afterward almost never does. The permit should say so, and the crew should expect the job to stop and be locked out at that point rather than continuing because the cover is already off and the shift is nearly over.