Interpreting NFPA 72
Engineers must understand how NFPA 72-2013 can be specified into commercial buildings. While the 2010 edition is just being put into practice in many jurisdictions, the changes to the 2013 code should be noted.
The edition of NFPA 72: National Fire Alarm and Signaling Code required for a project is typically determined by the edition of the standard referenced by the adopted building or fire code. Most jurisdictions are using the 2012 (or earlier) editions of nationally recognized building and fire codes, which reference the 2010 Edition of NFPA 72. Some jurisdictions, such as the state of Maryland, have recently adopted the 2015 edition of the International Building Code, in which the 2013 edition of NFPA 72 is the reference standard.
In addition, design professionals often consider the most recent edition of a reference standard because it typically includes the most recent technology and could be considered in determining the "standard of care." Newer editions of a reference standard may be used when approved by the code official or authority having jurisdiction (AHJ) using the concepts of alternative methods or equivalencies. The purpose of this article is to provide an overview of NFPA 72-2013 for both wired and wireless fire alarm systems, including identifying some of the significant changes to the 2013 edition.
Documentation (Chapter 7)
Building on the reorganization that occurred with NFPA 72-2010, the 2013 edition contains a new chapter titled "Documentation." The intent was to provide a central location for all the documentation requirements of the code. From the perspective of the design professional, Section 7.3 addresses the design documentation requirements. In many cases, the section refers the user to documentation requirements found elsewhere in the standard, such as identifying the acoustically distinguishable spaces (ADS) in accordance with 18.4.10 and specifying the rooms and spaces that will have visible notification in accordance with 22.214.171.124. Design documents are also required to include ambient sound pressure levels and audible design sound pressure levels in accordance with 126.96.36.199.3.
Fundamentals (Chapter 10)
Recognizing the confusion that has occurred regarding whether an initiating device should result in an alarm signal, supervisory signal, or trouble signal, the standard has been revised to define conditions that are detected. The conditions are a situation, environmental state, or equipment state of a fire alarm or signaling system. For example, a supervisory condition is defined as "an abnormal condition in connection with the supervision of other systems, processes, or equipment." The resulting signal from a particular initiating device is "a message indicating a condition, communicated by electrical, visible,audible, wireless, or other means."
There are times when the signal may be consistent with the condition detected or a signal that results in a higher level of response, such as an alarm signal. For example, while smoke detectors mounted in HVAC ducts are to initiate a supervisory signal, such detectors may also initiate an alarm signal under certain conditions (see 21.7.4). The actions to be performed upon receipt of a signal, referred to as the response, are based on the type of signal received.
Inspection, testing, and maintenance (Chapter 14)
Format-wise, the three tables from previous editions have been consolidated into two tables, one for inspection and one for testing. The methods that previously were in a separate table have now been included in the appropriate table associated with the component to be inspected or tested. However, the more significant change to Chapter 14 involves the deletion of requirements that are not related to the components of a fire alarm system. This change is in recognition of the new standard, NFPA 4: Standard for Integrated Fire Protection and Life Safety System Testing. NFPA 4 addresses the testing requirements for the integrated systems but not the individual fire protection systems.
For example, the fire alarm aspects associated with a smoke control system are tested in accordance with NFPA 72. The smoke control aspects (for example, air movement) of the smoke control system are tested in accordance with NFPA 92: Standard for Smoke Control Systems. However, the integration of the fire alarm system and smoke control system are tested in accordance with NFPA 4. These changes will obviously affect how a design professional develops the acceptance test protocols and commissioning plans for integrated fire protection and life safety systems.
Notification appliances (Chapter 18)
The use of the distinctive evacuation signal (the three-pulse temporal code) has been updated to extend to signals used for relocation and partial evacuation, not just complete evacuation as required by previous editions of NFPA 72. As such, this includes occupancies such as health care (Group I-2) and detention and correctional occupancies (Group I-3). Recognizing the expanded use of textual and graphical visible appliances, some provisions have been relocated from the chapter on emergency communications systems (Chapter 24). In addition, the provisions have been expanded to include fire alarm system applications and refined to include location, mounting, and performance requirements.
Emergency control functions (Chapter 21)
Consistent with the expanding use of occupant evacuation elevators, the requirements for such elevators have been revised to coordinate with changes in ASME A.17.1/B44: Safety Code for Elevators and Escalators. A waterflow switch may initiate elevator recall when sprinklers are installed in elevator pits.The waterflow switch is not permitted to have a time delay, and the piping shall be dedicated to the sprinkler in the elevator pit (see NFPA 72 21.3.3). Various updates also have been made for fire alarm systems interfacing with HVAC systems, for door and shutter release, and for electrically locked doors.
Protected premises (Chapter 23)
While numerous modifications have been made to the requirements for a protected premises fire alarm system, one of the more substantial changes involves addressing the monitoring of carbon monoxide detection systems. Carbon monoxide detector activations are to be displayed on the fire alarm system as"carbon monoxide alarm" signals. Carbon monoxide signals are to take priority over pre-alarm signals,which take priority over supervisory and trouble signals (see 10.7). Also, provisions have been added requiring that if a valve is installed in the connection between a sprinkler system and an initiating device, the valve is required to be supervised. With respect to wireless fire alarm systems, Paragraph 188.8.131.52 now requires that the fire alarm signal from a low-power radio transmitter latch at its receiver/fire alarm control unit until manually reset. The signal is required to identify the particular initiating device in the alarm. It should be noted that trouble and supervisory signals may be self-restoring and are not required to latch.
Emergency communications systems (Chapter 24)
Several changes have been made with respect to the use of microphones for live voice announcements. For example, a new requirement has been included to post instructions for the use of microphones in making voice announcements and for test messages to specifically state "this is a test." For emergency voice/alarm communication systems, the requirements for what should happen when the microphone is released after live voice instructions interrupt a recorded message have been clarified. For one-way emergency communication systems, messages shall be developed for each scenario in the emergency response plan and a message template shall be developed for each message. The message should include:
- What: guidance on what people should do
- When: an idea of when the occupants should act
- Where: a description of the location of the risk or hazard
- Why: information on the hazard, danger, and consequences
- Who: the name of the source of the warning.
With respect to mass notification systems, the control units are now to be listed in accordance with ANSI/UL 2572: Standard for Mass Notification Systems. It should be noted that a listed fire alarm system may perform emergency communication system functions, but a listed mass notification system may not be listed for fire alarm purposes. The requirements for the priority of voice messages have also been updated. Provisions have also been added on the use of textual and graphical visible notification appliances for primary or supplemental notification.
Requirements for the location and accessibility of emergency command centers also have been revised. The location shall be determined based on the risk analysis and approved by the emergency management coordinator.
Supervising station alarm systems (Chapter 26)
Changes have been made with respect to addressing alarm signal verification, alarm signal content, and restoration of signals. These changes have been made in part to help emergency responders better manage issues related to unwanted alarms. In addition, new definitions for unwanted alarms have been added to more precisely identify the sources of these alarms. While this article primarily focuses on the 2013 edition, the committees have completed processing the second draft of NFPA 72-2016. One area of contention with the second draft that is likely to result in a notice of intent to make a motion (NITMAM) is a change to the requirements for an alternate location for the receipt of alarm signals associated with a remote supervising station alarm system. The current text reads as follows:
The language in the second draft of NFPA 72-2016 is:
The concern is that the revision eliminates the role of the AHJ in the process of alarm signal management. If a NITMAM is submitted and certified by the NFPA standards council, the motion may be made during the association meeting in Chicago in June.
Incorporating the changes
This article does not address all of the changes in NFPA 72-2013, nor does space permit a complete discussion of all proposed changes to be included in the 2016 edition. Instead, it highlights changes that may be of importance to the design professional. As noted in the introduction, the design professional may use the 2013 edition when approved by the code official or AHJ as an alternative or equivalent to earlier editions. However, some of the requirements cited here do not conflict with earlier editions, and those changes could be incorporated into current fire alarm system designs as enhancing the minimum requirement of the 2010 edition.
William E. Koffel is president of Koffel Associates. He is chair of the NFPA Correlating Committee on Life Safety and a member of numerous NFPA technical committees. He is a member of the Consulting-Specifying Engineer editorial advisory board.