Fire alarms serve to alert the risk of fire and prompt timely evacuation. To serve their purpose, alarms must be in good working condition and they must rapidly detect a fire source anywhere within a building. To these ends, the National Electrical Code regulates the installation and maintenance of all fire alarms. In addition, the Occupational Health and Safety Administration, or OSHA, regulates fire alarms within the workplace.
In defining fire alarm systems, the National Electric Code includes all devices, including fire detection units, alarm-sounding devices and water sprinklers, all of which fall under NEC guidelines. The NEC prescribes that you install all fire alarm devices and cables in a neat and workmanlike manner. For example, support any cables so that normal use of the building will not damage them and use appropriate hardware to secure cables and label all circuits at their terminal and junction locations.
Alarms may be classified as non-power-limited fire alarm circuits or power-limited fire alarm circuits, with their electrical regulations varying in technical details. In either case, any fire alarm system must have its own branch circuit. These fire alarm circuits cannot have ground-fault circuit interrupters. These interrupters function by cutting off electrical current whenever they detect the circuit is touching ground. A fire alarm with such an interruption could cut itself off, without detection, and then fail to serve in case of emergency.
You must also house the fire alarm system separately from any electric light, power, broadband communication or other alarm circuits, never allowing them to share cable trays, compartments, enclosures, outlet boxes or other fittings.
The building and installation requirements for fire alarms extends to occupational settings, where OSHA imposes additional regulations beyond those of the National Electrical Code. The employer assumes responsibility for buildings to feature appropriately installed fire alarms. OSHA dictates that all devices must be installed in a way to comply with their intended function. For example, water sprinkler systems must effectively irrigate an area in accordance with their respective capacities. After each test or alarm, the employer must ensure that all alarms remain functional and in standard operating condition. The employer should also periodically check the condition of any fire alarms located in areas susceptible to corrosion and replace any damaged alarms. In such areas, the employer should cover the alarm unit with a canopy or hood. The location of the fire alarms must avoid undue risk of physical impact or damage, given the normal use of the building. Any fire alarms suspended from above must be secured with something other than their electrical wiring.