In many situations, the first indications of a fire could be faint traces of smoke or an increase in heat. In other scenarios, the first indication of fire is the immediate occurrence of flames.
FM Approved flame detectors are evaluated to detect the radiant energy from a fire. Some models monitor energy in the IR spectral band, some in the UV band and many monitor in multiple bands at the same time. Many flame detectors employ sophisticated algorithms such as flicker detection to discern real flames from other, non-fire sources of radiant energy. The manufacturer’s specifications regarding fuel types, distance and time to respond are all tested during the evaluation by FM Approvals.