BASIC TYPES AND CHARACTERISTICS OF FIRE DETECTION AND ALARM SYSTEMS.

There are four basic types of fire detectors - ionization, light (smoke), radiation (flame), and temperature. Each is activated by a different stage of a fire. The type of detector to be used depends in part on the nature of the area to be protected. For example, immediate, exorbitant losses would be experienced from fire in a computer room or tape-storage area. Therefore, an early-warning device would be desirable for such an area. Both ionization and smoke detectors are considered to be early warning devices. Flame detectors, although they respond almost instantaneously, are not considered to be early warning devices. Temperature detectors operate when the high-heat stage of a fire has been reached. At this point, significant damage will probably occur before the fire is extinguished.