Patent ID: 6958689

Claim:
A fire detector unit for detecting fire in a region, said unit comprising: a chemical sensor for monitoring said region for a combustion chemical and including a first measurable parameter which changes in value proportional to concentration levels of said monitored combustion chemical, said first measurable parameter being ambient temperature dependent; a temperature sensor disposed in proximity to said chemical sensor and including a second measurable parameter which changes in value proportional to the ambient temperature of said chemical sensor; and a processor circuit coupled to said chemical sensor and temperature sensor for reading said first and second measurable parameters thereof, said processor circuit operative to process said first and second parameter readings to generate a temperature compensated concentration level of said monitored combustion chemical based on a function of said first and second parameter readings and a selected one of first and second temperature factor values, each said first and second temperature factor value being based on first parameter measurements corresponding to a plurality of predetermined combustion chemical concentration levels, and to generate an alarm based on said generated temperature compensated concentration level.