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Author(s): Wayne Moore. Published on January 4, 2016.

Impairment Prep

Why it's important to plan carefully around fire alarm system testing impairments. BY WAYNE D. MOORE

THE FIRE PROTECTION INDUSTRY commonly accepts that the testing of a fire alarm system places the protected premises at risk during the test because the testing impairs a key component of the fire protection system. When this kind of fire alarm system testing occurs, the owner must have impairment plans in place to react to any real fire condition and provide proper notification to the occupants.

The individuals performing the fire alarm system tests must use common sense to ensure they complete the tests without misinterpreting the requirements of NFPA 72®, National Fire Alarm and Signaling Code. For example, large fire alarm systems may take more than eight hours to properly test. In such cases, each floor of the building should be tested and serviced before testing begins on the next floor. This would limit the length of an impairment on any particular floor and keep the majority of the system in service.

NFPA 72 defines an impairment as an “abnormal condition, during either a planned or emergency event, where a system, component, or function is inoperable.” A fire alarm system may experience either a planned impairment or an emergency impairment.

An example of an emergency impairment, as stated in the annex of the code, is physical damage to a control unit or wiring. By contrast, planned impairments may include the addition of new devices or appliances, the reprogramming of system software, or the testing of the fire alarm system. When testing a system, the code requires those who conduct the test to notify the owner or the owner’s designated representative whenever they impair a system or part of a system. Impairments to systems must include any out-of-service event.

The term “out of service” refers to any time the entire fire alarm system or a substantial portion of the system cannot operate as intended. This includes the disruption of an entire initiating device circuit, signaling line circuit, or notification appliance circuit.

The code requires the building owner to notify the authority having jurisdiction, typically the local fire official, whenever a system impairment exceeds a duration of more than eight hours. No matter how long an impairment may last, the building owner must always take appropriate measures to minimize the impact of the impairment.

The owner will need to determine the nature of the mitigating measures on a case-by-case basis. The owner must consider a number of factors: the building construction and occupancy type; the nature and duration of the impairment; the building occupancy level during the impairment period; the active work conducted on the fire alarm system during the impairment; the condition of other fire protection systems and features, such as automatic sprinklers and structural compartmentation; and the hazards and the assets at risk. Appropriate mitigating measures range from simple occupant notification that an impairment exists to a full-time fire watch making patrols throughout the impaired area.

Chapter 7 of NFPA 72 requires the preparation of a documented test plan describing the expected impairments, their anticipated duration and mitigation, and a plan to notify the occupants in the event a real fire occurs during the time the impairment to the fire alarm system exists. All parties—the owner or the owner’s designated representative, as well as the authorities having jurisdiction, including the fire department—must receive notification when the impairment resolves.

​WAYNE D. MOORE, P.E., FSFPE, is vice president at JENSEN HUGHES.