A Continuous Linear Fire Detector: Some Details of the Graviner Firewire Temperature‐sensitive System Available to Purchase

EXISTING fire detectors are mainly or the unit type, which is placed at a number of points in the fire zone. Fire will thus be detected when the temperature of one of the detectors is raised to its operating value by the flame, and if the fire happens to arise where there is no detector it will not be indicated until it has spread some distance. The unit detector can be very sensitive, but the operating temperature must not be set so low that it may be set off by ambient conditions short of fire, which may not be readily predictable. The unit detector also requires electric wiring, which must be in the fire zone, and an adequate number of detectors, with the necessary wiring, may well be heavy, apart from the difficulty of providing cables which will stand up to the fire zone conditions.