Patent ID: 7178381

Claim:
A portable gas detector comprising a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of the housing is provided as a functional part region, in which functional members related to a gas detecting operation are arranged, and a rear half portion in the interior of the housing is provided as a battery part region, in which a power source for driving the functional members is arranged, wherein the functional members, contained in the functional part region, comprise a sensor holder in which a plurality of gas sensors are held in a fixed state, said sensor holder having sensor holding parts for holding the gas sensors arranged in a plane, a sensor cap, in the interior of which a gas flowing path successively linked with the respective sensor holding parts has been formed, and at a position corresponding to at least one gas sensor, a filter assembly, operable for removing an interfering gas component related to the gas sensor, is detachably provided in the sensor cap exposed to a back surface of the housing.