Using NFPA 72 correctly

NFPA Journal, May/Jun 2002 by Richardson, Lee

NFPA staff answer some of the most frequently asked questions about this widely used code.

FPA 720(R), National Fire Alarm Code(R), is one of NFPA's most frequently used documents, and here are some of the most frequently asked questions about it.

Where does it specify that a fire alarm system is required and that automatic fire detection, occupant notification, and off-premises notification are required?

Although the requirements of NFPA 72 apply to the performance, installation, and maintenance of all fire alarm systems, the code doesn't specify when a fire alarm system is required. NFPA 101(R), Life Safety Code(R), and other codes enforced by the authority having jurisdiction determine whether a fire alarm system is required for an occupancy. These occupancy-based codes also specify the basic attributes of the fire alarm system. Such attributes typically include the type of signal initiation required, be it manual, automatic, or as a result of extinguishing system operation; requirements for occupant notification, both audible and visible; and requirements for off-premises emergency forces notification.

However, NFPA 72 amplifies on occupant notification in Section 3-8.4.1. This section requires that fire alarm systems used for evacuating or relocating occupants have notification appliances installed on each floor to meet the conditions specified in Chapter 4.

NFPA 72 also includes an automatic fire detection requirement in Section 1-5.6, which specifies that a smoke detector must be installed at the site of the fire alarm control unit if the unit is installed in an area that isn't continuously occupied. This requirement applies even if no other automatic detection devices are required.

What qualifications must designers, Installers, and service personnel have?

Section 1-5.1.3 of NFPA 72 requires that those who develop fire alarm system plans and specifications be experienced in the proper design, application, installation, and testing of fire alarm systems, and Section 1-5.1.4 requires that installation personnel be supervised by someone qualified and experienced in the installation, inspection, and testing of fire alarm systems.

Service personnel must also be qualified and experienced in the inspection, testing, and maintenance of fire alarm systems according to Section 7-1.2.2.

Examples of qualified personnel are included in the referenced code sections or in the related appendix sections.

What coverage Is required for automatic fire detection?

The type of coverage required for automatic fire detection is mandated by occupancy-based codes or local statutes. Section 2-1.4.2 of NFPA 72 addresses three types of required coverage: complete coverage, partial coverage, and selective coverage. Total coverage requires detection in virtually all accessible locations, although exceptions apply. Partial coverage includes common areas and workspaces, such as corridors, lobbies, storage rooms, equipment rooms, and other tenantless spaces. And selective coverage involves only spaces specifically required by occupancy-- based codes, statutes, or the authority having jurisdiction.

What do "public mode" and "private mode" mean?

The terms "public mode" and "private mode" refer to the way notification signals are used, not to whether the building is a public or private building. These terms are specifically defined in Section 1-4 under "operating mode."

Public mode operation can be viewed as the default mode for occupant notification. Audible and visible signals are directed to the occupants of the protected area, alerting them to take action to evacuate or relocate themselves as required. Private mode operation involves audible or visible signals only to persons directly concerned with implementing and directing emergency procedures. As an example, private mode operation may be used to alert attendants or others to evacuate occupants incapable of evacuating themselves.

NFPA 72 provides separate rules for notification appliances in each mode in Sections 4-3.2, 4-3.3, 4-4, and 4-5.

What's "central station" service?

The term "central station" is widely used in the fire alarm industry and is often used incorrectly to refer to any off-premises monitoring service. In NFPA 72 however, the term refers only to service provided to a subscriber under the structured contractual arrangements specified in Section 5-2.2.2. These arrangements involve providing six distinct elements: installation of fire alarm transmitters, monitoring of signals, retransmission of signals to the public fire service communications center, record-- keeping and reporting, testing and maintenance, and runner service. These elements can be provided by a "listed central station," by a listed central station that subcontracts certain local elements, or by a "listed fire alarm service-local company" that provides certain local elements and subcontracts certain remote and other elements to a listed central station.

The other two types of supervising stations the code recognizes are proprietary supervising stations and remote supervising stations. A proprietary supervising station is operated by the owner of the premises being monitored. A remote supervising station, while providing monitoring for variously owned premises, doesn't include the more structured contractual arrangements and other requirements specific to central stations. Sections 5-2, 5-3, and 5-4 include separate code requirements for each type of supervising station.