Most electrical contractors (ECs) ensure that they know the requirements of the National Electrical Code (NEC), and when they make a Code-related installation mistake, they expect the electrical inspector to advise them to correct it. That may not be the best way to install electrical systems, but it tends to be what some would call a “real-world” situation. Ideally, one would expect all areas of a professional contractor’s electrical installation to be Code-compliant. However, the NEC is more than just a list of rules for ECs to follow. It ensures all electrical systems are installed and operate safely. Therefore, a contractor should know the required codes in all installations and should not use the inspector to create a punch list of needed corrections.
ECs also must be thoroughly familiar NFPA 72-2007, the National Fire Alarm Code. Unlike the NEC, NFPA 72 provides application and installation requirements that the professional contractor must follow to ensure the life safety system performs reliably when it is needed. Many contractors feel NFPA 72 simply provides “guidelines” that they may or may not follow, depending on the project.
The scope of NFPA 72-2007 is clear: “NFPA 72 covers the application, installation, location, performance, inspection, testing, and maintenance of fire alarm systems, fire warning equipment and emergency warning equipment, and their components.” The code also clearly states its purpose is “to define the means of signal initiation, transmission, notification and annunciation; the levels of performance; and the reliability of the various types of fire alarm systems and the features associated with these systems and also provides information necessary to modify or upgrade an existing system to meet the requirements of a particular system classification.” And, the “code establishes minimum required levels of performance, extent of redundancy, and quality of installation but does not establish the only methods by which these requirements are to be achieved.”
Nowhere in the preceding excerpts from NFPA 72 did we see the word “guidelines.” The professional electrician who installs fire alarm systems should make sure that he or she understands all the requirements—including those from the NEC, Article 760 and all of NFPA 72-2007—associated with these installations.
NFPA 72’s various chapters contain requirements for applying and installing each type of fire system and for how to connect the system to off-premises alarm, supervisory and trouble signal monitoring, how to properly document the system information and how to properly test and maintain the system.
One of the first things a contractor should know is how to communicate clearly with suppliers, technicians and authorities having jurisdiction. Know the names and definitions of the typical components of a fire alarm system.
Chapter 3 of NFPA 72 provides this information. Some definitions follow.
- Fire alarm system: A system or portion of a combination of 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 those signals
- Fire alarm control unit: A component of the fire alarm system, provided with primary and secondary power sources, which receives signals from initiating devices or other fire alarm control units, and processes these signals to determine part or all of the required fire alarm system output function(s)
- Initiating device circuit: A circuit to which automatic or manual initiating devices are connected where the signal received does not identify the individual device operated
- Notification appliance circuit: A circuit or path directly connected to a notification appliance(s)
- Signaling line circuit: A circuit path between any combination of addressable appliances or devices, circuit interfaces, control units, or transmitters over which multiple system input signals or output signals or both are carried
- Addressable device: A fire alarm system component with discrete identification that can have its status individually identified or that is used to individually control other functions
- Heat detector: A fire detector that notes abnormally high temperature, rate of temperature rise or both
- Rate-of-rise detector: A device that responds when temperature rises at a rate exceeding a predetermined value
- Smoke detector: A device that detects visible or invisible particles of combustion
- Notification appliance: A fire alarm system component such as a bell, horn, speaker, light or text display that provides audible, tactile or visible outputs or any combination thereof
There are many more definitions of the components and operation of fire alarm systems that must be learned in order to communicate clearly when discussing anything related to fire alarm systems. The first step in becoming proficient in any field is to understand the vocabulary associated with it. The NFPA 72-2007 definitions is a good start for the professional wishing to expand efficiently and profitably into the fire alarm system installation field. EC
MOORE, a licensed fire protection engineer, frequent speaker and an expert in the life safety field, is a co-editor of the current National Fire Alarm Code Handbook. Moore is a principal with Hughes Associates Inc. at the Warwick, R.I., office.