Method and system for gas detection

Abstract

A system and method for using a gas detecting device that conducts electricity increasingly for increasing concentration of a gas being detected. The temperature of a gas sensor element is regulated to first burn-off impurities on the surface thereof, and then to cool down the gas sensor element to a temperature at or above which the gas catalyzes. During catalyzation, the sensor element conducts and electrically signals a microprocessor concentration data, which microprocessor controls a three color LED so as to emit a color pattern indicative of the concentration level of the gas. A sum of previously measured concentration levels is taken to gauge exposure to the gas over a period of time. The gas detection system includes a self-calibration routine that can be run prior to normal use by successive exposure to varying concentrations of gas to determine the sensor element-specific reaction. The sensor element output at each known concentration level is stored in nonvolatile memory during the self-calibration routine, which stored calibration data is compared to values measured during normal operation to accurately detect gas concentration levels. Audible alarms sound when the sum of previously measured concentration levels exceeds a predetermined hazardous level.