Case: the energized-conductor call and the walk-away
In one paragraph
A restaurant owner calls at 6 p.m. on a Friday: a 480-volt panel in the kitchen is buzzing, one of the walk-in coolers is dead, the dinner rush is starting, and 'you can't shut anything off.' Sam Okafor arrives, reads the arc-flash label, sees a failed breaker with a heat-damaged bus, and is told by the owner, the manager and the cook that the power stays on while he fixes it. He says no, explains the two lawful paths (a lockout of that panel section during a break, or a scheduled shutdown), and when the owner refuses both, he documents the hazard, hands over a written finding, and leaves without a fee. The owner calls back Monday. The names are invented; the safety orders are quoted.
The rule
Work on exposed energized parts is permitted only when responsible supervision has determined it must be done energized, the people involved are instructed, and insulated gloves or tools, barriers and eye protection are used, with insulated gloves required above 250 volts to ground and flame-resistant apparel for arc exposure (8 CCR 2320.2(a)); the decision belongs to the electrical contractor's responsible supervision, not the customer. Federal OSHA's parallel rule permits energized work only where de-energizing would create a greater hazard or is infeasible (29 CFR 1910.333(a)(1)), and a customer's business inconvenience is neither. Willful disregard of the safety laws is a licensing cause (B&P 7110(c)).
Why it matters
Every electrician has the call where the customer's schedule and the electrician's life are on opposite sides of a panel cover. The safety orders put the decision in your hands and nobody else's, and the walk-away is a skill: how to leave a paying customer with the truth in writing, no fee, and your name still the one they call Monday.