NFPA 72, Chapter 29, Single- and Multiple-Station Alarms and Household Fire Alarm Systems, is a code within a code. Most of the chapter in NFPA 72 are concerned with commercial fire alarm systems. Chapter 29 specifically states that Chapters 7 (Documentation), 10 (Fundamentals), 12 (Circuits and Pathways), 17 (Initiating Devices), 18 (Notification Appliances). 21 (Emergency Control Functions), 23 (Protected Premises), 24 (Emergency Communications Systems), 26 (Supervising Station Fire Alarm), and 27 (Public Emergency Reporting) do not apply to Chapter 29, unless otherwise noted.
Chapter 29 also states that smoke and heat alarms shall be installed in all occupancies where required by other laws, codes, and standard. However, Chapter 1 of NFPA 72 (Administration) does state that superior equipment and methods are acceptable. Since smoke detectors are superior equipment to smoke alarms, smoke detectors may be used in household fire alarm applications.
Chapter 29 Basic Requirements sets forth the requirements for installing smoke alarms and/or smoke detectors and offers two options:
Option one: install smoke alarms to satisfy the requirements of Chapter 29, with the option to install additional smoke detectors (connected to a fire alarm control panel) to duplicate the smoke alarms completely or partially.
Option two: install smoke detectors (connected to a fire alarm control panel) to satisfy the requirements of Chapter 29, with the option to install smoke alarms to duplicate the smoke detectors completely or partially.
Because the additional devices (smoke alarms or smoke detectors) are optional, the installation may be entirely smoke alarms or be a household fire alarm systems (smoke detectors connected to a fire alarm control panel).
Which option is used, detection requirements are the same. Chapter 29 requires detection in all sleeping rooms and guest rooms, outside each separate sleeping area within 21’ of the door, on every level (including basements).
If a household fire alarm system is installed, it is important that a control unit meeting the listing requirement for household fire alarm (UL 985) is used. Commercial fire alarm (UL 864) may also be used, but equipment that is not listed for fire alarm use is not permitted.
Household fire alarm systems require a battery with 24 hours standby capacity with 4 minutes of alarm capability. Primary power shall come from a dedicated branch circuit or unswitched portion of a branch circuit. Low power radio (wireless) systems are also permitted.