Ambient light level sensing

Automatic fire detectors are designed to sense the presence of a fire. They accompUsh this by detecting one of the elements of a fire heat, infrared or ultraviolet light radiation, and particulate aerosols, which are found in smoke. However, not all fires produce all of these elements, and some conditions that are unrelated to fires may produce certain of these effects. Therefore an effective fire detector must be able to differentiate between a fire condition and an ambient background level of these elements. Several types of detectors have been developed to sense fire elements. Some devices are single-function detectors while others may be designed to sense more than one element. 

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