So far, this column has discussed changes to Chapters 1–17 and the new Chapter 24, Emergency Communications Systems, in the 2010 National Fire Alarm and Signaling Code.
In Chapter 18, Notification Appliances, significant changes include the relocation of the requirements for the emergency evacuation signal (three pulse temporal pattern) from the protected premises chapter. New language was added to require that this signal shall sound for the appropriate time period but not less than three minutes. Effective Jan. 1, 2014, all audible notification appliances producing signals for sleeping areas will be required to produce a low frequency square wave signal with a fundamental frequency of 520 hertz. Studies have shown this type of signal to be more effective in alerting sleeping children and the elderly, who sometimes are not awakened by the sound of fire alarm signals.
Now that mass notification systems are being installed on a regular basis, intelligibility of emergency messages is more important than ever. Chapter 18 places more responsibility on the system designer and better describes where intelligibility is required. A new term, acoustically distinguishable spaces (ADS), was added. The ADS, as defined in the definitions chapter, is “an emergency communications system notification zone, or subdivision thereof, that might be an enclosed or otherwise physically defined space, or that might be distinguished from other spaces because of different acoustical, environmental, or use characteristics, such as reverberation time and ambient sound pressure level.” The code says each ADS must be identified as requiring or not requiring voice intelligibility.
Also, Chapter 18 now contains firefighter telephone mounting height requirements, which were relocated from the protected premises chapter to this chapter.
Chapter 21, Emergency Control Functions and Interfaces, is also new. Previously called “Fire Control Functions,” the requirements used to be in the protected premises chapter. New language identifies the installation wiring between the fire alarm control unit and the relay or control device and must be installed as Class A, B, D or X in accordance with Chapter 12. This is the first time this wiring identification has been described. The chapter also contains requirements for elevator recall and shutdown and new requirements for first-responder-use elevators and elevators for occupant-controlled evacuation.
Nothing significant was added to Chapter 23, Protected Premises. Much of the content for Chapters 12 (Classes and Styles of Circuits), 21 (Emergency Control Functions) and 24 (Emergency Voice Alarm Communications) was formerly in the protected premises chapter. The emergency evacuation signal information was relocated to the notification appliance chapter.
Chapter 26 is now called Supervising Station Alarm Systems, dropping the word “Fire” from the title because not only fire alarm systems are monitored. This edition strengthens new requirement for qualifications of supervising station operators was added in 2010. Although the requirements reside in Chapter 10, the supervising station committee is responsible for them. This edition strengthens a requirement that the authority having jurisdiction (AHJ) must be notified each year with documentation indicating who is responsible for the inspection, testing and maintenance of the remote station system. The major change is the elimination of four legacy transmission technologies no longer being installed. The “Other Transmission Technologies” subsection is used for methods other than digital alarm communicator transmitters (DACTs). There is still a great deal of confusion regarding the monitoring of fire alarm systems, but that will be covered in a future column.
The title of Chapter 27, Public Emergency Alarm Reporting Systems, was changed to delete the word “Fire,” and the scope was broadened to include monitoring of alarm systems other than fire alarm systems. It addresses requirements for the street boxes and municipal signal systems installed on the exterior of buildings that are connected to city circuits. Although these systems are still used in New England, they are not common in other parts of the country.
Chapter 29, Single- and Multiple-Station Alarms and Household Fire Alarm Systems, added language similar to Chapter 18, Notification Appliances, for the requirements of low-frequency square wave signals to alert occupants in sleeping areas. Language was added to address the interconnection of smoke alarms using wireless technology and new guidance for the placement of smoke alarms and detectors.
Last but not least, two annexes were added. Annex C addresses system performance and design and D addresses speech intelligibility. Annex D is primarily based on the NEMA Guide SB-50 and is available for download as a PDF file at no charge from the www.NEMA.org.
Many jurisdictions have adopted NFPA 72 2010. You must learn it.
HAMMERBERG is currently the president/executive director of the Automatic Fire Alarm Association Inc. headquartered in Jasper, Ga. He serves on a number of NFPA committees, including the NFPA 72 Technical Correlating Committee and the Protected Premises Technical Committee. He can be reached at TomHammerberg@afaa.org.