When I discuss a fire alarm system with a contractor in the field, they always state their system installation complies with NFPA 72 2019, National Fire Alarm and Signaling Code. So, when I ask which chapter in the code they used, they often say the one that applies to buildings.

First, all chapters except Chapter 29, Single- and Multiple-Station Alarms and Household Signaling Systems, apply to commercial fire alarm systems installations. That said, if you were not connecting the building system to a supervising station, Chapter 26, Supervising Station Alarm Systems, would not apply. The chapter the contractor referred to is Chapter 23, Protected Premises Alarm and Signaling Systems.

The chapter states in the first paragraph of Section 23.1, “The application, installation, and performance of alarm and signaling systems within protected premises shall comply with the requirements of this chapter.” The Annex A.23.1. further clarifies, “Chapter 23 is intended to cover alarm and signaling systems and their components, such as fire alarm, mass notification, carbon monoxide, and other signaling systems.”

At this point, it looks like the contractor is spot on. That is, until you read the next section, which states “The requirements of Chapters 7, 10, 12, 14, 17, 18, 21, 24, and 26 shall apply unless otherwise noted in this chapter.”

The systems that Chapter 23 covers are for life safety, property protection or both. This is also the location of the requirements for all software-driven fire alarm systems. There appears to be some misinformation regarding software use, but the code is clear from the beginning of an installation.

A record of installed software and firmware version numbers must be prepared and maintained in accordance with Chapter 7, Documentation. Software and firmware (nonchangeable in the field) within the system that interfaces to other required software or firmware must be functionally compatible.

Compatibility between software systems is necessary to ensure the systems can communicate correctly and the overall system can function as intended. Unfortunately, even software that is compatible can become incompatible when updated. Newer software revisions might not maintain compatibility with older revisions, so it is important to test system operation when the software is changed in any way.

The amount of testing Chapter 14 requires will depend on the extent the software was changed and what was affected. Additionally, compatibility between systems will be documented in one or the other (or both) of the manufacturer’s installation documents for the compatible products and controlled by the listings agencies. This documentation will be referenced in the product’s marking.

The compatible software or firmware versions must be documented at the initial acceptance test and at any reacceptance tests. The documentation is allowed to be paper copy or electronic media. When a software revision changes, the documentation can be consulted to ensure it is still compatible with the software or firmware on the other side of the interface or that the components installed all work properly with the new software.

There is a new section in the 2019 edition of Chapter 23 that allows separate fire alarm, carbon monoxide or other life safety systems if they do not send conflicting signals to the occupants or the actuation of any safety function.

Keeping in mind that the code is not a design guide, fire alarm systems serving a building must include one or more of the following: manual fire alarm signal initiation, automatic fire alarm and supervisory signal initiation, monitoring of abnormal conditions in fire suppression systems, actuation of fire suppression systems, actuation of emergency control functions, and actuation of fire alarm notification appliances.

Also, the system design, including all of its operating features, must be documented.

All of the above are the minimum requirements for a fire alarm system installation in a new building. The design features of a required fire alarm system installation must be based on other applicable codes or statutes the enforcing jurisdiction has adopted.

The code recognizes that owners may wish to install a fire alarm system in their building even when the codes in the jurisdiction do not require them to do so. In these cases, the system designer must establish the goals and objectives with the owner but must still meet NFPA 72 2019 requirements. The fact that the building or life safety code does not require a system doesn’t mean you can install whatever you want without following the code.

Although the contractor at the beginning of this column was on the right track, he and you need to know that all chapters of NFPA 72 2019 must be used to ensure a proper system design and installation.