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Wiring Outside the Box
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Mace to launch dealer program, acquire central station Basics of establishing an employee ID badging system The security week that was: 1/02/09 The top 40 security stories of 2008 Homemade bombs force evacuations in Aspen, Colo. Toronto wraps up municipal surveillance pilot project
Normally, the fire alarm initiating device, notification appliance and signaling line circuits are not run outside the building. When we have no choice but to run them overhead or underground, locating the applicable rules in NFPA 72 can be tough. It’s especially tough when 72 refers you to an entire code section in another standard to find the information you’re looking for. In the “Fundamentals” chapter of the National Fire Alarm Code, we find the following:
“4.4.4.3 Transient Protection. To reduce the possibility of damage by induced transients, circuits and equipment shall be properly protected in accordance with the requirements of NFPA 70, National Electrical Code, Article 800.”
In the next section, 4.4.4.4, NFPA 72 requires compliance with the NEC, and adds “specifically” with Article 760. Only two parts of Article 760 apply to our power limited wiring methods. And it says “See Parts I and III” for the power-limited wiring rules. Part I of 760 contains a single sentence declaration of the “Scope” of Article 760, a few definitions, followed by a list of 11 other NEC Articles that also apply to 760.
As it turns out, Article 760 gives more precise directions for locating the transient protection rules we’re looking for:
“760.32 Fire Alarm Circuits Extending Beyond One Building. Power-limited fire alarm circuits that extend beyond one building and run outdoors… shall meet the installation requirements of Parts II, III, and IV of Article 800…”
Article 800 looks to only be about telephone wiring, and in fact, is named “Communication Systems.” Upon closer scrutiny, the “Scope” of Article 800 states that it covers “communications circuits and equipment.” Article 800 then defines a communication circuits as:
“The circuit that extends voice, audio, video, data, interactive services, telegraph (except radio), outside wiring for fire alarm and burglar alarm from the communications utility to the customer’s communications equipment up to and including terminal equipment such as a telephone, fax machine, or answering machine.”
