Issue 29: Changes to the 2010 National Fire Alarm and Signaling Systems Code
By Robert Schifiliti, P.E., FSFPE
The 2010 edition of NFPA 72 will be titled "National Fire Alarm and Signaling Systems Code." Much like the company that was once known as a "copier" company and changed to the "document company," this new Code name reflects some substantial changes in scope. This title change recognizes that NFPA 72 addresses signaling systems used for more than just fire hazards. Systems used for weather alerts and warnings, terrorist attacks, chemical releases and other threats are now directly incorporated in NFPA 72.
In addition to the name change, there are structural changes aimed at making the Code easier to navigate and easier to grow in the future. The document has been organized into four major subject groups as shown in Figure 1.
Although chapters are numbered up to 29, there are only 14 used in the 2010 edition. This allows for future changes and expansion without having to relocate existing text. These 14 chapters represent the 11 chapters of the 2007 edition plus three new chapters.
12 – Circuits and Pathways
21 – Emergency Control Functions and Interfaces
23 – Emergency Communications Systems
Table 1 is a list of all chapters and annexes in the new Code.
The most significant change in this edition is also the one that led to the reorganization: the addition of a new chapter to address Emergency Communications Systems (ECS). This new chapter was born out of the need for standards addressing in-building mass notification systems (MNS). The Fire Protection Research Foundation has conducted a number of research programs under the umbrella of "optimizing notification systems." One program found that tone-only signaling was only effective with highly trained and non-transient populations and that voice and text communications were much more effective in general.1 This study was, in part, another supporting factor in the reorganization of the Code to increase the prominence of Emergency Communications Systems.
Introduced as an Annex in 2007, MNS applications have increased significantly to include wide-area mass notification systems and distributed-recipient mass notification systems. Wide-area mass notification systems are used in emergencies to communicate to a large or disperse population in large contiguous geographical areas (Wide-Area) using sound and voice (giant voice systems), signs, TV and radio. Distributed-recipient mass notification systems communicate discretely and directly to a number of people using cell phones, pagers, text messages or other personal communications systems. Emergency communications systems also include in-building fire emergency voice alarm communications systems (EVACS), formerly located in the protected premises fire alarm systems chapter. With this edition of the Code, it is now acceptable, some would say preferred, that ECS be combined with general paging and voice communications.
Two-way in-building ECS has requirements for two-way wired emergency services ECS – often referred to as fire fighters' telephones. Recognizing the preference of many emergency services organizations to use their own radios in buildings rather than the fixed phone system, this section of the chapter has new requirements to ensure proper planning, design and installation of these systems. These new requirements, as well as the associated testing and inspection requirements for the radio systems, were developed in a coordinated effort with NFPA 12 and NFPA 1221.3 The category of two-way in-building ECS also includes area of refuge ECS and elevator ECS.
The last category of ECS is information, command and control. This section addresses communications methods and equipment used to receive and transmit information between a premises system and one or more central control stations. This permits an in-building ECS to communicate with, and even be controlled by, a secure external command station, whether fixed or mobile.
As more and more facilities incorporate voice communications for ECS and general paging and communication systems, there is a need to educate designers, installers, testers and authorities having jurisdiction (AHJs) about intelligible voice communications.4 A guide for designers and installers has been developed by an industry organization.5 In addition, The Fire Protection Research Foundation conducted a program to develop a guide test protocol that also addresses certain planning and design factors.6 Much of that report has been incorporated as new Code Annex D, "Speech Intelligibility."
A significant change in the body of the Code is the addition of the requirement in Chapter 18, "Notification Appliances," for designers to plan and designate acoustically distinguishable spaces (ADS). This requires designers to establish and document which spaces, if any, will require intelligible voice communications. There is considerable discussion in the Annex to point out that intelligible voice communication is not necessary in all spaces and that it might not be possible in certain circumstances. By forcing designers to list or otherwise document these spaces and conditions, the Code ensures that system goals be documented and agreed to by all interested parties.
A new chapter titled "Circuits and Pathways" consolidates all circuit installation and performance requirements formerly located in the "Fundamentals" and "Protected Premises" chapters. This was done so that all of the different systems chapters could point to one location for circuit and pathway requirements.
This change and the expansion to incorporate new types of systems also triggered the need for a new, easier and more flexible method for circuit and pathway designation and for new ways of looking at circuit survivability. Performance based circuit designations are now the same regardless of the circuit function. Survivability of circuits and pathways are now described as levels 0 through 3. Although called "levels," they are not intended to be hierarchical since different hazards require different protection mechanisms – because the Code addresses more than just fire hazards.
"Emergency Control Functions and Interfaces" is a new chapter formed from 2007 section 6.16, "Protected Premises Fire Safety Functions." This chapter addresses the interconnection of emergency control functions, such as elevator and HVAC control, to fire alarm systems and to emergency communications systems.
Two research programs supported by The Fire Protection Research Foundation under the umbrella of "optimizing notification systems" have led to new code requirements for tones used to awaken people. Previous editions of the Code have not specified any particular frequency content for audible tones. Most fire alarm and smoke alarm tones for new equipment use sounders that produce high frequency tones on the order of 3,150 Hz.
This frequency band is also the one where most adults experience hearing loss. Two research programs have shown that a low frequency, 520 Hz square wave signal can awaken and alert people with hearing loss and alcohol impaired adults.7,8 The notification appliances technical committee (Chapter 18) has written a code requirement for all sleeping area signals to use the new low frequency signal effective January 1, 2014. This applies to new system activated signals.
The use of speakers and amplifiers that also provide voice capability is an easy way to accommodate this need. Other hardware solutions may also be used. The effective date allows time for system product development and listing. The technical committee on single- and multiple-station alarms and household fire alarm systems (Chapter 29) has incorporated the same low frequency signal requirement for residential protection without an effective date. This would require that any smoke alarms or household systems use the 520 Hz square wave signal if the 2010 edition has been adopted in the particular jurisdiction.
There are many more changes in the new 2010 edition of NFPA 72. A cross reference index in the Code maps the new 2010 edition to the 2007 edition. Also, there are a number of presentations planned at local SFPE chapters that will help users identify and understand the new Code.
Robert Schifiliti is with R. P. Schifiliti Associates, Inc.
- Gwynne, S., Optimizing Fire Alarm Notification for High Risk Groups: Notification Effectiveness for Large Groups, The Fire Protection Research Foundation, Quincy, MA, June 2007.
- NFPA 1, Fire Code, National Fire Protection Association, Quincy, MA., 2009.
- NFPA 1221, Standard for the Installation, Maintenance, and Use of Emergency Services Communications Systems, National Fire Protection Association, Quincy, MA., 2010.
- "Speech Intelligibility", Fire Protection Engineering, Issue No. 16, Fall 2002.
- NEMA Standards Publication SB 50-2008, Emergency Communications Audio Intelligibility Applications Guide, National Electrical Manufacturers Association, Rosslyn, VA, 2008.
- Grant, C., Intelligibility of Fire Alarm & Emergency Communication Systems, The Fire Protection Research Foundation, Quincy, MA, November 2008.
- Bruck, D., and Thomas, I., Waking effectiveness of alarms (auditory, visual and tactile) for adults who are hard of hearing, The Fire Protection Research Foundation, Quincy, MA, June 2007.
- Bruck, D., Thomas, I., and Ball, M., Waking effectiveness of alarms (auditory, visual and tactile) for the alcohol impaired, The Fire Protection Research Foundation, Quincy, MA, June 2007.
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