Understanding Residential Fire Alarm Systems

Feb. 19, 2009
Go to the codes and get up to date

Here’s a question that begs an answer: Would you walk into a customer’s home and knowingly eliminate their “code mandated” fire detection device? Hopefully, the answer is a resounding “no.”

Yet every day, alarm dealers and system integrators are regularly doing just that, and worse.

Far too often installers without the pre-requisite training on the fire and building codes are installing alarm systems in residences and effectively placing the building occupants in potential jeopardy should a fire or emergency situation occur. Here’s some information you need to know to fully understand residential fire alarm systems and the role of the systems integrator and installer.

Let’s start with these basic definitions:
Smoke Alarm – a single or multiple station alarm responsive to smoke. (NFPA 72(07)-3.3.180) These devices are designed to meet the requirements of ANSI/UL 217, Standard for Safety Single and Multiple Station Smoke Alarms.

Smoke Detector – a device suitable for connection to a circuit with a sensor that responds to a physical stimulus such as heat or smoke. (NFPA 72(07)-3.3.43) These devices are designed to meet the requirements of ANSI/UL 268, Standard for Safety Smoke Detectors for Fire Alarm Signaling Systems.

Fire Alarm System – a system or portion of a combination system that consists of components and circuits arranged to monitor and annunciate the status of fire alarm or supervisory signal-initiating devices and to initiate the appropriate response to these signals.( NFPA 72(07)-3.3.67)

Initial considerations
Far too often in this industry installers use terms which sound synonymous with other terms, yet in fact mean very different things as they pertain to the legal and code defined meanings.

Terms such as smoke alarm and smoke detector are used interchangeably – yet mean dramatically different things (as noted above).  The same is true to the terms Alarm Monitoring Station and Central Station.  Each of these terms describe a specific level of contracted service – yet they are used interchangeably – potentially to the detriment of the installing company.

Common mistakes
Installers regularly deploy residential alarm systems without considering several of the basic code requirements listed below.

Required Detection – Where required by applicable laws, codes or standards for a specific occupancy, approved single- and multiple-station smoke alarms shall be installed as follows:
• In all sleeping and guest rooms
• Outside of each separate dwelling sleeping area
• On every level of a dwelling unit, including the basement
• In the living area of a guest suite.
• In additional areas as may be required by applicable laws, codes or standards for a specific occupancy type.

NFPA 72(07)-11.5.1, &
Far too frequently systems are installed/designed to meet the financial limitations / restrictions of the home builder or homeowner, without adequate understanding on their part of the code requirements listed above.

Installers need to educate the various system stakeholders as to not only the applicable code requirements but the life safety implications of NOT installing a code compliant system.

Inadequate Notification – In jurisdictions where the local AHJ allows the use of a Household Fire Alarm System in place of the code required smoke alarms dealers frequently neglect the requirements for notification appliances. NFPA 72(07)- specifically requires that Household Fire Alarm Systems meet the notification appliance requirements of NFPA 72(07)-7.4.2 (Public Mode Audible Requirements) and 7.4.4 (Sleeping Area Requirements).

In a typical single family environment this would mean that in the living areas of the residence the notification appliance shall have a sound level at least 15dB above the average ambient sound level, or 5dB above the maximum sound level (having a duration of at least 60 seconds), whichever is greater.

In the sleeping areas the notification appliance must meet the above or have a sound level of 75dBA, whichever is greater, as measured at the pillow.

Installers are reminded that had single or multiple station smoke alarms been installed in this residence that each smoke alarm’s integrated sounder would have ensured compliance with the codes notification requirement, but due to the installation of a fire alarm system, notification appliances were necessary to accomplish the same requirement.

Additional consideration should be made in selecting sounding devices which are listed and designed for the intended purpose. This means using alarm sounders and sirens which are listed for Household Fire Alarm Systems.

Combination System – In this era of programmable systems, most residential alarm systems are capable of performing multiple functions, from intrusion detection, to medical emergency notification, to controlled access and fire detection.
Installers are reminded that although the code allows for the use of combination systems in household applications, the code is very specific on the conditions under which these Household Fire Alarm Systems must operate.
Specifically, these systems must:

• Use equipment which is listed for the intended purpose.  (NFPA 72(07)-11.3.1)   This means that the system must be listed for use as a Household Fire Warning System (UL 985). 
• Ensure that fire signals take precedence over any other signal or function, even if the non-fire signal activates first. (NFPA 72(07)-
• Have two independent power sources, one which is the commercial light and power and the second that consists of a rechargeable battery. (NFPA 72(07)-11.6.2 (1))
• The secondary power source must be capable of powering the system for at least 24 hours in normal conditions followed by four minutes of alarm. (NFPA 72(07)-11.6.2 (2)) Additionally, it must be supervised for removal, disconnection or a low battery condition. (NFPA 72(07)-11.6.2 (3)) And it must be capable of recharge within 48 hours. (NFPA 72(07)-11.6.2 (4b))
• Possibly the most important item to consider is that a combination system providing only intrusion detection would best be described as a “burglar alarm,” but introduce just one fire detection device to the system and it now becomes a “household fire alarm system” which also provides intrusion detection.
In plain terms this means that the installer absolutely must consider what type of system this will be before running any wires or purchasing any peripheral equipment.

System Wiring – Where common wiring is employed for a combination system, the equipment for other than the fire alarm system shall be connected to the common wiring of the system so that any fault in this equipment or interconnection between this equipment and the fire alarm system wiring does not interfere with the supervision of the fire alarm system or prevent alarm or trouble signal operation.  (NFPA 72(07)-
What this means to the installers is that all wiring associated with the “fire alarm” portion of the system must be installed in accordance with NFPA 70, National Electrical Code, Article 760.  (NFPA 72(07)-11.8.5)

This includes such peripheral devices as:
• System keypad
• System transformer
• System notification appli-ances (sounders)
• All devices “powered” by the fire alarm system (this could mean your security system devices if they share power from the system integral power supply).  If this is unacceptable, then the installer may segregate the security devices to an auxiliary power supply used solely for the security devices, and independent from the fire devices powered by the control panel.

It should also be noted that had this system originally been installed as a security only system and the fire detection added subsequently, the installer would need to potentially replace some of the system wiring with fire-rated wiring.

Alarm Monitoring – Where it is desired to connect the household fire alarm system to a remote monitoring station, this service also is regulated through various sections of the code.

Specifically, NFPA 72(07)11-7.8 outlines the parameters under which a system shall be monitored. The monitoring services shall be preformed as outlined in NFPA 72(07) Chapter 8, with the following modifications:

• The system shall only require one telephone line.
• The system shall transmit at minimum a monthly test.
• The remote monitoring station may verify the alarm signal, as long as it is does not delay fire service notification for longer than 90 seconds.

While none of these modifications are earth shattering, the installer can wade into dangerous waters if they convey to the customer that their system is reporting directly to the fire department, to the “central station,” or some other simplification of the alarm monitoring process.

As mentioned above, this industry uses many terms “generically” to describe many of the services provided.

A clear and concise understanding of NFPA 72(07) Chapter 8, will explain to the installer the dramatic differences between the various alarm monitoring functions available.  And hopefully, keep them from misleading the customer or promising services that they cannot, or do not, truly provide.

Writer’s Note: This article has attempted to provide an overview of a very unique segment of the industry. The insights and observations have been provided as a beginning guide to aid you in understanding some of the opportunities and obstacles you may face.

Given the life safety nature of the system installed, installers should take extra care to ensure that the installed system meets the applicable code requirements for their area.
All code references have been paraphrased – and the reader is encouraged to read the entire referenced code in its full context.

Additional information and understanding can be gained by furthering your formal training on this topic at one of the upcoming NBFAA National Training School (NTS) classes held across the country.

Significant portions of this article were excerpted from various NBFAA National Training School courses. With over 35,000 individuals attending NTS courses since its creation in 1985, it is clearly the “Gold Standard” for training individuals on the fundamentals of the Electronic Life Safety and Security Industry.

About the Author:
Dale R. Eller serves the NBFAA as their Director of Education and Standards. A 25-year industry veteran, Eller’s firm ITZ Solutions! provides consulting, training and management services to the NBFAA, PBFAA, NYBFAA, Installation Quality Certification Program and WISE.