Your questions answered: Notification systems and NFPA 72-2022

Fire signaling and notification system questions are answered here

By Consulting-Specifying Engineer December 27, 2023
Fire alarm requirements are driven by many codes and standards. NFPA 72 requires the “how to” for fire alarm systems when the systems are required by other codes. Courtesy: Consulting-Specifying Engineer

During the live webcast on Nov. 14, 2023, many questions were left unanswered. First, watch “Fire, life safety: Notification systems and NFPA 72-2022,” then read the responses below.


  • Ray Grill, PE, Principal, Ray Grill Consulting
  • Chris Campbell, PE, Principal & Founder, Campbell Code Consulting

Does NFPA 72: National Fire Alarm and Signaling Code require addressable notification appliances?

Chris Campbell: There is no requirement for addressable notification appliances in NFPA 72.

Does the International Building Code require a mass notification system for all Group E occupancies.?

Chris Campbell: In the 2021 IBC and previous editions, there is no requirement for mass notification in Group E occupancies. Beginning in the 2024 IBC, Group E occupancies requiring a fire alarm system and having an occupant load over 500 require a mass notification risk analysis conducted in accordance with NFPA 72. A mass notification system is only required if the risk analysis determines there to be a need.

For corridors, can you clarify if having strobes within 15 feet of the end of corridors is still required if following the typical room spacing guidelines in the corridors?

Ray Grill: NFPA 72 allows the visible notification room spacing criteria and/or the corridor spacing criteria when designing strobe coverage for corridors. Both approaches can be used in the same corridor. If you are using the room coverage approach for an end of a corridor and the rating of the strobe covering the end of the corridor is such that it does not need to be placed within 15 feet of the end wall, you do not have to place a strobe within 15 feet of that end of the corridor.

In the context of this webcast, do you consider mass notification system to mean fire alarm voice communication system?

Ray Grill: The simple answer is no. However, a voice alarm system can be used to provide direction to occupants regarding actions needed for other than fire emergencies. When the criteria for mass notification was first added to the code as an annex, the intent was for fire alarm systems to also be allowed to perform other emergency notification functions. NFPA 72 does not limit the use of a voice alarm system to only produce fire alarm messages. There are product standards for mass notification (UL 2572) that were developed after the addition of mass notification in NFPA 72. Most if not all major fire alarm manufacturers now have their products duel listed to UL 864 and UL 2572.

Is fire alarm audibility required in all occupied spaces of a building?

Chris Campbell: Generally, yes, with some exceptions. For example, audibility is not required in all spaces in a Group I occupancy where private mode signaling is used. Another example is where the average ambient noise is greater than 105 dBA, in which case a visible notification appliance is provided and audible notification appliances are not required.

Is private mode signaling permitted by the IBC in Group I occupancies?

Chris Campbell: Yes, when installed in accordance with NFPA 72 and approved by the fire code official. Refer to IBC 907.2.6.

Is speaker/strobe required in nonregularly occupied spaces? i.e., electrical rooms etc.

Ray Grill: The IBC and NFPA 72 require audibility in occupiable spaces within the building. NFPA 72 defines an occupiable area as an area of a facility occupied by people on a regular basis. The IBC defines an occupiable space as a room or enclosed space designed for human occupancy in which individuals congregate for amusement, educational or similar purposes or in which occupants are engaged at labor, and which is equipped with means of egress and light and ventilation facilities meeting the requirements of this code. Unless you also have offices for maintenance staff within the electrical rooms or mechanical rooms, they are not occupiable areas and are not required to have notification.

Are 520 Hertz 120-volt smoke detectors specifically required by NFPA 72-2022 to be installed in sleeping areas/units even though those devices are not yet being manufactured?

Ray Grill: NFPA 72 doesn’t require the use of 120-volt smoke alarms. NFPA 72 provides the performance criteria for detection and notification. The 2021 IBC added language requiring low frequency sounders in sleeping areas of R-2 occupancies when a fire alarm system is required. If a fire alarm system is not required in the building, in my opinion, 120-volt single-station or multiple-station smoke alarms can be used within dwelling units. If the building requires a fire alarm system, then system devices with low-frequency sounders or other means such as integrating smoke alarms with system powered low-frequency sounders using control modules would need to be provided to achieve code compliance under the 2021 IBC.

When would you recommend the use of a conventional fire alarm system versus an addressable fire alarm system?

Ray Grill: The only time I would recommend a conventional system would be for a limited area that has a single initiating device zone.

For K-12 facility renovation of a 1960s facility, are fire alarm voice annunciation required for audible fire alarm devices in renovations?

Ray Grill: Renovations of existing systems can be a little tricky. Many jurisdictions have policies on the extent of work that necessitates bringing the entire system up to current code. There isn’t any specific guidance in the IBC or International Fire Code on when an entire system needs to be replaced. Based on the International existing building code, the upgrade of a fire control panel due to lack of parts, etc. could be considered a repair and not require other portions of the system to be upgraded. Often the upgrade of a panel can require initiating devices that are no longer compatible with the new control equipment to be changed, but notification appliances are often maintained. Given the current state of affairs regarding other potential emergency situations arising, it could be an opportunity for the school to upgrade the emergency communications by adding voice. NFPA 72 allows a voice evacuation system to be used for other purposes, therefore it could be used to communicate other emergencies to occupants.

Standard practice appears to be providing a smoke detector in storage closets. I believe this was due to when flammable liquids were stored there. Is it technically required?

Ray Grill: Unless you have a special hazard addressed by the building or fire code, smoke detectors are not required in closets. I often see smoke detectors in electrical rooms and mechanical rooms of office buildings that are fully sprinkled protected. These smoke detectors are not required by code.

Where is alarm verification in NFPA/IBC?

Chris Campbell: Alarm verification is defined in Chapter 2 of the IBC. In the 2022 Edition of NFPA 72, alarm verification requirements can be found in Section