Fire Code Confusion: Occupancy Types

Feb. 13, 2018
NFPA 72 Chapter 29 creates conundrums for fire alarm technicians

You may be surprised how much NFPA 72’s chapter on “Single- and Multiple-Station Alarms and Household Fire Alarm Systems” has changed the landscape of the code throughout the years.

Years ago, NFPA 72 was a short standard on the specific subject of fire alarm systems. Before 1993, several standards and two guides were all published separately, including NFPA 74, the “Standard for Installation, Maintenance, and Use of Household Fire Warning Equipment.”

Then, in 1993 these separate codes and guides were compiled together and published as the new, improved and larger NFPA 72, the National Fire Alarm Code. The old NFPA 74 became the “Household Chapter” of NFPA 72, Chapter 2.

From the beginning, Chapter 2 seemed out of place – both figuratively and literally. With each edition of NFPA 72, the Household Chapter added more and more requirements for commercial residential occupancies, and continued to mandate a minimum level of protection.

The rest of the chapters in NFPA 72 state installation and equipment rules for notification and initiating devices, etc., without regard to specific rooms or spaces of particular occupancy types. Although minute “levels of protection” have creeped into some chapters – such as the requirement for a smoke detector over control panels in rooms not continuously occupied, and the inclusion of at least one manual pull box for buildings with a sprinkler system but no fire alarm system, etc. – no other chapters have been so blatant and bold as the Household Chapter when it comes to stepping on the role of the Building Codes for a particular occupancy type.

The Household Chapter of NFPA 72 did not remain as Chapter 2; in fact, with each revision of the code, it was decided to move – and keep – the Household Chapter as the final chapter.

That leads to our reader question: When do I follow Chapter 29 of NFPA 72, and when do I follow the Building Code? Are there times when I should follow both?


Protection Dictated by Occupancy Type

The rules of NFPA 72 regarding fire alarm equipment, services, and/or features, was only applicable when these items were required by the adopted Building Code, which sets the minimum safety provisions for new buildings.

Specific occupancy types – as defined by these adopted Building Codes – are given a level of protection considering the number of occupants, their activities, their risk factors and other considerations. In other words, the level of protection should be set by the adopted Building Code –based on the occupancy type – for a jurisdiction.

In the case of “one- and two-family” occupancies, for example, a Building Code separate from commercial construction requirements was created and has since been adopted by every state. Known as the International Residential Code (IRC), it includes a section for the minimum requirement smoke alarms, as well as a section for the alternative use of a fire alarm system, to meet the stated level of protection. Section 314 of the IRC states what type of detectors can be used and what areas in the home are to be protected. It also specifies that the “equipment” meet the listing, function and installation requirements of NFPA 72 Chapter 29 – which has been the Household Chapter for many years.

As you probably know, when a requirement is stated in an adopted Building Code, it supersedes the rules of any standard that may cover the same subject; therefore, you follow the IRC as to where and when to install detectors, and you follow NFPA 72 regarding the equipment itself. Thus, while it is always permitted and desirable to install additional protection, the additional rules of Chapter 29 are not required to be followed in order for you to meet the provisions of the Residential Building Code.

When does this delineation come into play? Here’s an example: A new rule in NFPA 72 requires one smoke detector/alarm for every 500 square feet of floor space on a single level (added in 2013 to better protect large, sprawling, ranch-style homes). It does NOT have to be followed when your state has adopted the IRC, because the IRC does not include this provision in its “where required” section; however, the notification requirements in NFPA 72 will have to be met when installing a smoke detection system in a one- or two-family home, as the IRC has stated that the equipment must meet the provisions of NFPA 72.

29.3.7 in NFPA 72 states that the audible sounders must meet the Public Mode provisions of Chapter 18 (i.e. 15 dB over average ambient in occupiable areas and 75 dB at the pillow). Like the new rules for commercial buildings with sleeping areas, if your homeowner customer informs you he has mild to severe hearing loss, then says you will sell him audible appliances for his bedroom that include a low tone frequency of 520 Hz. Additionally, if he tells you he has moderate to severe hearing loss, you will also sell him a strobe light for his bedroom as well as a tactile appliance, such as a bed shaker.


The Household Chapter: Always in the Back

Here’s a related reader question: Why are half the Chapters of NFPA 72 now blank?

Since it was the intent to keep the Household Chapter as the last chapter in the book, and not move it every time a new chapter was added, other blank chapters were created to keep from re-numbering the Household Chapter (29). It was decided to keep it the last chapter in the book is because Chapter 29 is Occupancy Specific, and could possibly be used as a Code, rather than part of a Standard.

It may one day disappear from NFPA 72, and re-appear as a separate Standard – just as it originally started out. Yes, Chapter 29 is to blame for all the blank chapters now a part of NFPA 72.

Because Chapter 29 insists on being an “odd duck” by including a protection level and specific occupancy type requirements, it does not meet the same stated guidelines followed by the rest of the chapters in NFPA 72. Whether it will eventually be removed is yet to be determined.

Use the adopted Building Code in your state to learn what equipment and features are to be installed in a specific occupancy. Then, use NFPA 72 – Chapters 1 through 29 – for learning how to install the equipment and features your Building Code requires. Think of Chapter 29 as the ugly duckling hiding amongst the swans.


Greg Kessinger has been SD&I’s fire alarm and codes expert and a regular contributor for more than 15 years. Please email him your fire & life safety questions for potential inclusion in this column at