Free checklist
Duct smoke detector quarterly maintenance checklist
A quarterly duct smoke detector round is short on purpose: it catches the wear items that fail between annual services. This checklist is sized for a tech with a phone. Every item says what to look at and the photo that proves the round happened. Work is commonly verified against NFPA 72, NFPA 90A. Confirm the edition your authority having jurisdiction has adopted.
The checklist
Every item, and the photo evidence it needs
The photo count on each row is what RTI would require before the item can be submitted. Work the list here and watch the gate hold, or load it into RTI and let it enforce the real thing.
Sampling and detector
Sampling tube orientation and exhaust tube observed
Inlet sampling tube spanning the duct with its holes facing into the airflow, exhaust tube fitted, tubes not crushed, loose at the duct wall or plugged.
Detector head and housing cleanliness checked
Detector head and sampling chamber free of heavy duct dust or grease film, housing gasket seated, cover latched and the sensing chamber not visibly fouled.
Detector status LEDs read at the housing
Power or normal indicator showing its normal pattern at the housing, with no alarm or trouble LED lit.
Housing mounting, conduit and wiring entries secure
Housing tight to the duct or its bracket, flexible conduit and fittings secure at the entries, nothing shaken loose by air handler vibration since the last round.
Housing free of tape, bags or covers from nearby work
No dust bag, tape or plastic left over the housing or its cover by trades working near the unit, so the detector is still sampling duct air.
Remote station and access
Remote test/reset station and LED observed
Remote station LED in its normal state, station accessible and not painted over or blocked, its location matching the unit it serves.
No photoLabeling and access to the detector checked
Detector and the unit it serves labeled to match, mounting accessible for service, no ductwork or ceiling change that has buried the housing.
Status and history
Detector point checked at the panel for trouble or dirty alerts
Where the detector is addressable, its point at the panel shows normal with no maintenance, dirty or drift alert, and any alert noted for the annual cleaning.
No photoAlarm and trouble history for this detector reviewed
Work orders and panel events since the last round checked for nuisance trips or troubles on this detector, with repeats flagged to the fire alarm contractor.
No photoAir handler status matched to the detector's normal state
Unit running or off as its schedule calls for, not held off by a latched detector, and not found running with its shutdown wiring disconnected.
No photo
Close out the round
Ceiling tiles or access doors used to reach it put back
Any ceiling tile or access door opened to reach the detector closed again, with the housing and any remote station left reachable for the next visit.
No photoFindings reported to the owner and the fire alarm contractor
Fouled heads, misaligned tubes, dark LEDs and blocked access sent to the owner and the fire alarm contractor, with the detector ID and the unit it serves.
No photo
What usually sends this back
The failures are almost always the evidence, not the work
- Sampling tube installed backwards or its inlet holes rotated out of the airstream, so the detector is live and reporting but never actually sampling moving air.
- Detector head caked with duct dust and read as clean from the walkway, when the buildup is exactly what drives the nuisance trips that get the whole detector bypassed.
- Remote test/reset station LED dark and unnoticed because the station is in a ceiling or a back corridor nobody passes.
Common questions
6 answers
- What does this duct smoke detector quarterly checklist cover?
- 12 items across 4 sections, covering sampling and detector, remote station and access, status and history, close out the round. Each item spells out what the person walking the job is actually looking for, not just a box to tick.
- Who should run this inspection?
- The building engineer or HVAC tech reaching the detector at the air handler on the quarterly round, recording condition rather than performing the actuation test.
- When in the schedule should this walk happen?
- Every quarter, walked with the air-handler check since a fouled detector and a dirty duct show up on the same visit.
- Why do these items ask for a photo?
- 6 of the 12 items call for photo evidence, 7 photos in all. A checklist answer without the photo is a claim; the photo is what makes the record worth something in a dispute and lets a reviewer approve work without re-walking the job.
- What most often fails a duct smoke detector quarterly inspection?
- Sampling tube installed backwards or its inlet holes rotated out of the airstream, so the detector is live and reporting but never actually sampling moving air. Detector head caked with duct dust and read as clean from the walkway, when the buildup is exactly what drives the nuisance trips that get the whole detector bypassed. Remote test/reset station LED dark and unnoticed because the station is in a ceiling or a back corridor nobody passes.
- Can I use this checklist in RTI?
- Yes. Start a free RTI workspace, build this list as a checklist, and the Photo Gate holds the submit button until every mandatory item is answered and its photos are attached. Approved inspections roll into a branded turnover package with a tamper evident audit trail.
Run it with the Photo Gate
A checklist nobody can submit half-finished
Load this list into RTI, stick a QR tag on the area it covers, and the submit button stays locked until every mandatory item is answered and the 7 required photos exist. Approved walks roll into a branded turnover package with a tamper evident record behind every line.
See all 508 checklists · 6741 items and 5984 photo requirements in total.