Lone Night-Shift Power Supply Replacement in a Skilled Nursing Facility
At 21:00 you are the only technician dispatched to a 96-bed skilled nursing facility to replace a failed notification appliance circuit power supply. The fire alarm panel sits in a 34-inch-wide janitor closet, and the supply enclosure is about 18 inches from a sprinkler riser. The 120 V feed comes from a breaker in a locked mechanical room, labeled FIRE ALARM - DO NOT TURN OFF, with no lockout device installed. The facility has no fire watch contract and the administrator is not on site. You estimate 90 minutes of work. Your company policy requires two technicians for panel work above 50 V, and the on-call helper is 45 minutes away. The step ladder in the van is 6 ft. The night nurse asks whether the alarm will be off while you work.
1. Identify the hazards and procedural gaps in this job before you open the enclosure.
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Electrical
- The circuit is 120 V, which is above the company's 50 V threshold, so the two-technician rule applies. The helper being 45 minutes out does not waive it; the correct move is to wait or reschedule.
- The breaker has no lockout means. Lockout/tagout requires a lock I control, a tag, and verification by testing that the circuit is dead. A label saying do not turn off is a warning, not a lock.
- The breaker label must be verified, not trusted; mislabeled breakers are common, so test before touching.
Physical
- The closet is 34 inches wide with a sprinkler riser 18 inches away: cramped working clearance, head-strike and pipe-damage risk, and poor escape path.
- A 6 ft ladder in a closet that narrow invites side-loading. Confirm it fits, is set on a stable surface, and is not placed where a door can hit it.
Life safety
- Replacing the supply takes the NACs out of service in a building full of people who cannot self-evacuate, at night, with no administrator present and no fire watch plan.
Any one of these would justify stopping; together they make the job a reschedule.
2. What is the correct impairment procedure if the work does go forward?
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Before power is removed
- Get the administrator or the designated responsible person on the phone and get an authorized decision, in writing if possible.
- Notify the supervising station and the AHJ that the notification circuits will be out of service, with start and expected end times.
- Establish the compensating measure: a documented fire watch with a defined route and interval, or staff patrols if the AHJ accepts them. In a nursing home this is normally a fire watch, not a verbal 'we will keep an eye on it.'
- Record the impairment at the panel and in the log.
During the work
- Lock and tag the breaker, verify the circuit is dead with a meter, and keep the key with me.
- Keep the impairment as short as possible; have the replacement supply staged and tested before pulling the old one.
After
- Restore power, confirm normal supervision, test each affected notification circuit, and notify the supervising station and AHJ that the impairment is cleared.
- If the work cannot be finished, do not leave the building with circuits down and no fire watch. Restore what can be restored and escalate.
3. The night nurse asks if the alarm will be off and whether she needs to do anything. What do you tell her, and why does that matter for the exam-level judgment here?
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I would tell her plainly: yes, the horns and strobes on this circuit will be silent while I work, the rest of the system stays monitored, and she and the charge nurse need to start the fire watch now, walking the wing on a set interval and logging it. I would also give her my cell number and a realistic finish time.
The judgment point is that the technician is the only person on site who understands what the impairment means. Facility staff often hear 'the alarm is off' as a minor inconvenience. Translating it into a concrete action, a route, an interval, and a log entry is part of the job, not a courtesy.
Equally, I would not let the nurse's question pressure me into starting. Her question is a signal that the building is depending on a system that is about to be partly disabled, which strengthens the case for waiting for the second technician and the administrator rather than working alone above 50 V in a cramped closet at night.