Author(s): Richard Roux. Published on May 1, 2018.

Smarter About Smoke

A look at five key changes to the 2019 NFPA 72, including a game-changing new smoke alarm requirement that could dramatically reduce household nuisance alarms


NFPA 72®, National Fire Alarm and Signaling Code®, is adopted in virtually every state and in countries around the world, and changes to the code can impact a wide range of stakeholders. There were more than 600 proposed changes for the 2019 edition—some minor, others obviously significant. Attendees at this year’s NFPA conference in Las Vegas will have opportunities to learn about specific changes to NFPA 72 firsthand, including a pair of interactive education sessions as well as the Technical Meeting on Thursday, June 14.

NFPA Conference Sessions
NFPA Conference & Expo, Las Vegas, June 11-14, 2018

NFPA 72–2019, National Fire Alarm and Signaling Code, Proposed Changes: Panel Discussion, Part 1
Tuesday, June 12, 11 a.m.–noon

Merton Bunker, Louis Berger US; Warren Olsen, FSCI; Daniel O'Connor, Manuelita David, and Jeff Moore, Jensen Hughes; David Lowrey, City of Boulder Fire Rescue

NFPA 72–2019, National Fire Alarm and Signaling Code: Changes for Fire Service Access Elevators and Occupant Evacuation Elevators
Tuesday, June 12, 11 a.m.–noon

Sagiv Weiss-Ishai, SFFD

NFPA 72–2019, National Fire Alarm and Signaling Code, Proposed Changes: Panel Discussion, Part 2
Wednesday, June 13, 11 a.m.–noon

Merton Bunker, Louis Berger US; William Koffel, Koffel Associates, Inc.; Jack Poole, Poole Fire Protection, Inc.; Laurence Dallaire, Architect of the Capitol

NFPA 72 Document Information Webpage

Learn more about upcoming NFPA 72 webinars, online learning programs, and training courses, and purchase the 2019 edition of the National Fire Alarm and Signaling Code Handbook, available in print and pdf in October and eBook in November.

One key change is the addition of a date: January 1, 2022. That’s the day NFPA 72 will require all new installed household smoke alarms to meet listing specifications to distinguish between smoke generated by routine cooking and smoke generated by potentially more serious sources, such as furniture.

This push to develop more discriminating smoke alarms is a direct response to the problem of nuisance alarms, which leads many residents to remove alarm batteries or entire alarms, significantly increasing occupants’ risk of death or injury in a home fire. The listing requirements were developed by UL at its new testing facility, and the inclusion of the date in the new NFPA 72 underscores what is arguably the most important lifesaving change in smoke alarms since their introduction in the 1960s, along with codes to require their installation.

The addition of January 1, 2022, marks a milestone in smoke alarms, but it isn’t the only big change for the 2019 NFPA 72. Here’s a look at a handful of the most important proposed changes to one of NFPA’s most widely used codes.

January 1, 2022

The 2019 edition of NFPA 72 establishes the date for enactment of the requirement such that any smoke alarm installed within 20 feet—10 feet for photoelectric alarms—of a stationary or fixed cooking appliance must be specifically listed for installation in close proximity to cooking appliances.

NFPA 72 provides requirements on where to locate (and not locate) smoke alarms to minimize unwanted alarms. Many of these requirements pertain to smoke alarms installed near kitchen areas. Many homes include functioning smoke alarm installations, but owners view them as annoyances because they believe the alarms often operate needlessly, often as a result of smoke generated by routine cooking. Nuisance alarms are the leading reason for disconnected smoke alarms; in more than half of the reported fires where smoke alarms do not operate, batteries are missing or disconnected.

In an effort to reduce unwanted alarms caused by cooking, NFPA has led the way in requiring a special listing for household smoke alarms. As a result of the need for this special listing requirement, listing agencies, with the help of industry experts and the Consumer Product Safety Commission, have collaborated to create a new test for smoke alarm designs to demonstrate a much higher immunity to cooking smoke and byproducts. Beginning in 2020, UL, which developed the testing for the listing, will no longer list smoke alarms that are unable to pass a series of tests designed to prove their resistance to cooking and other sources of false alarms. (For more on how the testing was developed and what it means for consumers and the safety industry, see “Smoke Signals” in the March/April NFPA Journal.)

Among NFPA 72 committee members, concerns arose that, following the logic as provided by the code, there could now be two smoke alarm types—one specifically listed for installation in close proximity to cooking appliances, and one that must still be listed but not specifically for this installation location. In theory, every smoke alarm on the market would now have two models, which could lead to confusion and misapplication. After much discussion, it was determined that all smoke alarms would need to be subjected to the new tests, and that such a requirement would reduce the number of models that manufactures, distributors, installers, and contractors would need to consider. No one would have to worry about specifying, installing, and verifying installation of cooking proximity vs. non-cooking areas.

NFPA 72 requires that all devices comply with applicable standards such as ANSI/UL 217, Standard for Single and Multiple Station Smoke Alarms. UL has completed and has now published the eighth edition of ANSI/UL 217, and manufacturers can submit their products for listing under the new edition. Any new smoke alarms and all current smoke alarm models still to be manufactured need to be tested/retested and evaluated and listed to the eighth edition or other applicable standard in order to be installed after January 1, 2022.

Integrating NFPA 720 into NFPA 72

NFPA 720, Installation of Carbon Monoxide (CO) Detection and Warning Equipment, will be retired in 2018, and the requirements from NFPA 720 have been integrated into NFPA 72.

This change collects the requirements for smoke alarms, carbon monoxide alarms, smoke detectors, and carbon monoxide detectors in the same document. Several task groups and technical committees worked for over three years to integrate the requirements into one comprehensive document.

Today, 38 states require some form of carbon monoxide detection in homes. Some states require installation only in new construction, while others require installation only when there is an attached garage or similar feature. Some of the requirements are by state statute, and others are by adoption of a building code or via an amendment to a state building code. Some states require carbon monoxide detection in schools while others require them in hotels and motels.

Carbon monoxide incidents are on the rise. Data shows that, in 2003, U.S. fire departments responded to an estimated 51,700 non-fire CO incidents where carbon monoxide was found. During 2006–2010, by comparison, municipal fire departments responded to an annual average of 72,000 carbon monoxide incidents, excluding incidents where nothing was found or fire was present.

The changes that address carbon monoxide in NFPA 72 are significant. Most will reside in Chapter 29, Single- and Multiple-Station Alarms and Household Signaling Systems; Chapter 23, Protected Premises Alarm and Signaling Systems; and Chapter 14, Inspection, Testing, and Maintenance. Chapter 29 addresses the use of single station CO alarms in household settings, and the requirements are relatively similar to the use of single-station smoke alarms. Many home installations choose protection with the installation of a household fire alarm system with smoke detectors, and, with the incorporation of NFPA 720 into NFPA 72, with carbon monoxide detectors. In many cases, these household systems incorporate security alarm functions and are monitored off-site, and in some applications the signals can be forwarded to smart phones or other mobile devices.

Chapter 29 is most significant as it addresses carbon monoxide detection in homes. According to recent data, 89 percent of reported non-fire CO incidents took place in homes (defined as one- or two-family dwellings, manufactured homes, and multifamily dwellings, including apartments, condos, town houses, row houses, and tenements). By contrast, homes accounted for 75 percent of the structure fires reported.

Chapter 23 addresses the addition of independent carbon monoxide detection systems in environments other than households. Detection can be monitored by a standalone carbon monoxide detection panel or integrated with the building fire alarm system.

Fire service access elevators and occupant evacuation elevators

Significant changes have been made to NFPA 72 regarding elevators, with the section on Fire Service Access Elevators essentially rewritten and the section on Occupant Evacuation Elevators (OEE) extensively changed. Many of these changes pertain to the programming and interface between the fire alarm control unit and the elevator controller. Other changes address in-building fire emergency voice/alarm communications system messaging during elevator operation scenarios.

A document developed by the American Society of Mechanical Engineers, ASME A17.1-2016/CSA B44–16, Safety Code for Elevators and Escalators, addresses the design, construction, installation, operation, testing, inspection, maintenance, alteration, and repair of elevators, dumbwaiters, escalators, moving walks, and material lifts. The code covers equipment and associated parts, rooms, spaces, and hoistways, where located in or adjacent to a building or structure. Although A17.1 is the code that governs the elevators, it references NFPA 72 for the installation of smoke detectors, other initiating devices, elevator recall, elevator shutdown, and other equipment necessary for these features to communicate and function. NFPA 72 contains several sections in Chapter 21, Emergency Control Function Interfaces, that provide requirements for Elevator Phase I Emergency Recall Operation, Elevator Power Shutdown, Fire Service Access Elevators, and Occupant Evacuation Elevators.

Communications methods for forwarding signals from protected premises to supervising stations

Another change for the 2019 edition of NFPA 72 addresses the communications methods used to forward alarm and other signals from a protected premises to a supervising station. The change appears in fewer than a dozen locations in Chapter 3 and Chapter 26 of the code, but it provides an important clarification while acknowledging the bigger picture of technological changes in our communications environment.

A decade ago, the 2007 edition of NFPA 72 noted a variety of communications methods for forwarding signals from the protected premises to the supervising station. To use a digital alarm communicator transmitter (DACT), a primary line as well as a secondary line were required. The primary line was required to employ one telephone line, while the secondary line could be a cellular telephone connection, one-way radio system, one-way private radio alarm system, private microwave radio system, two-way radio frequency (RF) multiplex system, or a transmission means complying with Paragraph 8.6.4. The DACT was required to be connected to the public switched telephone network (PSTN).

When it came to newer telephone technologies, the 2010 edition of NFPA 72 was a game-changer as a result of its redefinition of public switched telephone network (PSTN), the communications equipment and telephone service providers that allowed users to establish communications channels via discrete dialing codes. The 2010 edition marked the first time the code addressed newer digital communications technologies such as Internet protocol, fiber optics, and cable. This meant these newer technologies, or the service providers that utilized these methods, could be used to establish communications channels if they complied with the requirements of NFPA 72.

The 2010 edition also introduced the concept of the managed facilities-based voice network (MFVN), which was a newer technology subset of a PSTN—the term MFVN was added to distinguish it from a traditional PSTN. The code defined an MFVN as a physical facilities-based network capable of transmitting real-time signals with their formats unchanged. This network is managed, operated, and maintained by the service provider to ensure service quality and reliability from the subscriber location to the PSTN interconnection points or other MFVN peer networks.

Changes continued in the 2013 edition. The primary line remained, but the secondary line design choices were reduced to a one-way private radio alarm system, two-way RF multiplex system, or a transmission means complying with Paragraph If the protected premises did not have access to two technologies for the DACT, the code provided an exception: with the approval of the authority having jurisdiction (AHJ), a second telephone line could be utilized as the secondary means. DACT requirements changed little in the 2016 edition, and the 2019 version continues to require two lines.

The significant change for 2019, though, is the elimination of the term “public switched telephone network” and its acronym, PSTN, in favor of MFVN. With the continuing communications shift away from traditional public switched telephone networks—and their eventual replacement by newer technologies and greater access to broadband—the code recognizes and permits the use of alternative communications technologies. The elimination of the term and its acronym is the next step in the code’s evolution. System owners, supervising stations, and municipalities must understand these changes to communications technology to ensure compatibility of equipment and compliance with the code.

Class N pathways enhancements

The 2016 edition of NFPA 72 added the concept of Class N pathways, which addresses Internet infrastructures for alarm and signaling systems in buildings. There were a number of proposals and comments related to Class N pathways for the 2019 edition, and the code has been revised to include and simplify many of these criteria.

Traditionally, the distributed components of a fire alarm system have connected using two-conductor cable. This cable interconnects all of the fire alarm initiating devices and fire alarm notification appliances to a fire alarm control unit using signaling line circuits, initiating device circuits, and notification appliance circuits. However, with the proliferation and availability of computer networks, we can now “connect” to almost every communication device we use through Ethernet or other computer networks, and rigorous computer networks exist in many buildings.

The Class N circuit includes two or more pathways that have their operational capability verified through end-to-end communication. The redundant path intends to compensate for Ethernet wiring that cannot meet all of the fault monitoring requirements that normally apply to traditional wiring methods used for fire alarm circuits.

Important changes related to Class N pathways include design considerations where a device failure resulting from a multiple ground-fault pathway failure could render an area or zone incapable of initiating input signals or receiving output signals; greater control of the design and installation by the AHJ; and additional marking and access considerations for the Class N life safety networking cable, equipment, and associated infrastructure. Other criteria include significant detail on the required risk analysis and specific testing criteria.

Looking ahead

Be sure to attend the Technical Meeting on Thursday, June 14, where eight NFPA documents, including NFPA 72, will be on the agenda.

Six notices of intent to make a motion (NITMAMs) have been certified for NFPA 72 and will be discussed and voted upon by the membership. NITMAMs address occupant relocation or evacuation during an alarm; use of Temporal 3 pattern; duration of alarm signaling for evacuation; intelligibility; and the Standard Emergency Service Interface, all from Chapters 18 and 24. The final NITMAM addresses the receipt of signals at a central station, from Chapter 26.

With the conclusion of the Technical Meeting, the Standards Council is scheduled to issue the 2019 edition of NFPA 72 in mid August. The document will be available in pdf form at the end of August and in book format at the end of September.

RICHARD ROUX is staff liaison to NFPA 72. Top Photograph: Getty Images