Fire / non fire discrimination device and fire alarm

摘要

PROBLEM TO BE SOLVED: To provide a fire decision device which effectively determines a fire with low power consumption, and a fire alarm using the fire decision device.;SOLUTION: The fire decision device includes a smoke sensor 4, a CO sensor 3, a calculation means 2 of calculating a smoke density gradient Gs, a smoke density difference maximum value |d|max, and a CO density gradient Gco, and an elapsed time measuring means 2 of measuring an elapsed time Ts until smoke density reaches first set smoke density and second set smoke density higher than it, and determines a fire on the basis of the smoke density gradient Gs, the smoke density difference maximum value |d|max, the elapsed time Ts, and the CO density gradient Gco. The smoke density gradient Gs is calculated by estimating, as measurement data of initial-point density, measurement data closest to the first set smoke density among measurement data of initial-point density detected first exceeding the first set smoke density and a plurality of measurement data which are measured previously and at least include last measurement data.;COPYRIGHT: (C)2010,JPO&INPIT