Gas sensor calibration system

摘要

The present invention provides a method of calibrating sensors within a gas detector ( 36 ) having a housing containing a gas inlet whereby gas can diffuse from the inlet to the sensors. The gas inlet in the housing is held against part ( 34 ) of the calibration apparatus to form a sealed gas interface between the apparatus and the detector; a source ( 10 ) of pressurized calibration gas is connected to the apparatus, and a predetermined dose of calibration gas is delivered to the interface between the detector ( 36 ) and the calibration apparatus ( 34 ) at a predetermined pressure. The source ( 10 ) of pressurized calibration gas may contain single or multiple calibration doses and, if the former, the calibration apparatus includes a dosing system such as cylinder ( 14 ) for metering individual doses of calibration gas.