AN EXPERIMENTAL-STUDY OF A DETECTOR-OPERATED WATER DISCHARGE SYSTEM TO ENHANCE LIFE SAFETY

This paper presents the results of nine from a series of 51 instrument ed full-scale fire tests designed to demonstrate the feasibility of us ing a detector-operated water discharge system to enhance the life saf ety of occupants of limited mobility in the room of fire origin. Tests were conducted in a room 4.0 m long x 3.6 m wide x 2.4 m high using b oth smouldering and flaming fires. The length of rime available for es cape from the room was obtained by comparing the time of detection wit h the earliest onset of a hazardous condition as determined by a life threat model. The system incorporated a multi-sensor, two-stage fire d etection algorithm using signals from an optical smoke sensor and a he at sensor. Three sensitivity settings of the detection algorithm were assessed. It was found that at the highest sensitivity, the frequency of false alarms was likely to be unacceptable, whilst at the lowest se nsitivity, the detection algorithm might fail to detect a fire before conditions within the room became a threat to life. The results show t hat by using the intermediate sensitivity for the detection algorithm, the system was able to respond to smouldering fires before the onset of hazardous conditions and before domestic sprinklers would operate. With fast flaming fire scenarios, the performance of the system was fo und to be comparable to that which would be expected from domestic spr inklers. (C) Crown Copyright 1996 Published by Elsevier Science Ltd.