To maintain stable detection accuracy for a long time by correcting a discrimination level corresponding to the change characteristics or fluctuation characteristics of a gas sensor with the passage of time or corresponding to seasons concerning a gas leak alarm.
This concerns a gas alarm provided with a gas sensor 2 to change its electric characteristics by detecting gas, a heater 3 for heating this gas sensor 2 to a prescribed temperature, a temperature sensor 4 for measuring the temperature of the gas sensor 2 and a control means for controlling the heater 3 based on the temperature of the gas sensor 2 measured by this temperature sensor 4, for processing the output signal of the gas sensor 2 and performing warning operation when that output signal exceeds a discrimination level, wherein the detection accuracy of the gas sensor 2 is corrected corresponding to cumulative operating time from the time point of operation start as an alarm or the fluctuation corresponding to seasons.
OCHIWA SHINICHI
TSUDA KOICHI
ONODERA KATSUMI
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