Tie Tenant Duct-Detectors to Building Fire Alarm?

10/27/2025

Good morning, I am in Florida and use the Florida Fire Prevention Code 8th Edition, which references NFPA 1 and 101 (2021), NFPA 72 (2019), NFPA 96 (2021), and NFPA 17A (2021).

I have a mixed occupancy strip mall that is fully sprinklered and has a fire alarm that was initially installed to monitor the sprinklers only.

One tenant upgraded the panel to accommodate a full fire alarm for their unit.

A different tenant, mercantile class C, in the strip mall has installed a hood and hood suppression system along with duct detectors for their upgraded AC system. The ducts serve only their unit and do not cross demising walls or serve other units.

My interpretation is that the duct detectors and hood suppression systems must be tied into the building's fire alarm.

Is this correct?

Another question, would this tenant then need to upgrade their unit to include pulls and notification appliances?

Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

6 Comments

Chad

10/27/2025 07:25:52 am

The hood system has to be monitored by the fire alarm.

2024 NFPA 101 9.8.2.2
The actuation of an extinguishing system that is not installed in lieu of a required, supervised automatic sprinkler system shall be indicated at the building fire alarm system, where provided.

2022 72.17.14* Detection of Operation of Other Automatic Extinguishing Systems.

The operation of fire extinguishing systems or suppression systems shall initiate an alarm signal by alarm-initiating devices installed in accordance with their individual listings.

Duct smokes as well, 90A:
11.4.4.2

In addition to the requirements of 11.4.3, where an approved fire alarm system is installed in a building, the smoke detectors required by the provisions of Section 11.4 shall be connected to the fire alarm system in accordance with the requirements of NFPA 72.
'
They do not have to be fire alarm devices though. They can be supervisory. And for a sprinkled strip mall, IMO they should be supervisory. If it was an I, E, H or other critical B occupancy, then fire alarm.

Glenn Berger

10/27/2025 09:28:19 am

Total agreement with Chad. I was involved with the duct detector issue with USACE last week for a project in Alaska.

Ricardo Gonzales

10/27/2025 11:04:35 am

I disagree with the above gentlemen. 1st. The building has a sprinkler monitoring system is it not a Fire Alarm System.

The tenant installed a kitchen hood that is not required to be monitored if a Fire Alarm system is not installed. One isn't. The same goes for the Duct Detectors. IF a Fire Alarm system is installed.

This is the line where often others call a 'Sprinkler Monitoring System' a 'Fire Alarm System'. They are different. Now IF it's being classified as a Fire Alarm System by the AHJ, note that full notification will need to be installed throughout the building. i.e. tripling the cost to the client and the building owner. A fire alarm system provides full notification for the tenants, and a sprinkler monitoring system only provides the one outside for the FD.

Robert Morgan

10/27/2025 01:05:46 pm

I agree with Mr. Gonzales here,
This is a specific function fire alarm system only designed to monitor the sprinkler system. The hood suppression and duct detectors in a single tenant should not require monitoring by the sprinkler monitoring FA. If a tenant (like a daycare center) which required a fully compliant NFPA 72 FA system were to take a space or more, that tenant would have to have proper notification and activation appliances and would need to be monitored by the "building alarm" in that a flow anywhere in the strip would trip that units devices.

10/27/2025 01:54:03 pm

From the OP" One tenant upgraded the panel to accommodate a full fire alarm for their unit."

Although it might have been voluntary and only offer partial, once you add notification devices, their is implied protection and it needs to be connected. I doubt there is a true fire separation in there. This may vary from AHJ to AHJ but is readily enforceable.

Plus AHJ can always pull the because I said so card with:
4.4.4* Occupant Notification.

In every building or structure of such size, arrangement, or occupancy that a fire itself could not provide adequate occupant warning, fire alarm systems shall be provided where necessary to warn occupants of the existence of fire.

Jim (OP)

10/29/2025 10:18:38 am

Thank you all for the insight and a lot to chew on. I appreciate all of the expertise! This is a great forum.

Tie Tenant Duct-Detectors to Building Fire Alarm?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES