Fire & LIfe Safety: Melding Cameras with Fire Detection

Also: More on duct detectors

NFPA 72 ( allows for devices that are an “integral part of the fire alarm system” to drop standby power during primary power outages. The only reason duct detectors must be supervised by a fire alarm system — and only when it is a code-required fire alarm warning system — is to provide better annunciation then the HVAC contractors who provide placards that read, for example, “RTU #7” or “AHU #14”, when they are supposed to indicate the location of the detector and area served by the air handling unit. It is for this reason only, that the fire alarm company gets involved with these mechanical systems. Monitoring the duct detector’s contacts for a supervisory signal is the (only) stated requirement.


Greg Kessinger is SD&I’s resident fire alarm and codes expert and a regular contributor. Reach him at