Gas concentration detector comprises oxide semiconductor gas sensor, heater, device for calculating comparison, and device for determining when ratio of required level to compared level exceeds predetermined value

摘要

Gas concentration detector comprises oxide semiconductor gas sensor (10a) having stable region and unstable region and producing required level by calculating gas concentration; heater (10b) to introduce heat to sensor; device for calculating comparison; and device for determining when ratio of required level to compared level and/or difference between levels exceeds predetermined value.