A METHOD OF OPERATING A GAS SENSING DEVICE, AND CORRESPONDING GAS SENSING DEVICE

A method of operating a gas sensing device is described. The device comprises a gas sensor circuit comprising a resistive gas sensing element, and a control circuit. The method comprises receiving (202) a signal indicative of a value of resistance of the gas sensing element, processing (204) the signal received to compute a value of a gas concentration, performing a comparison (206) of said value of gas concentration to a threshold, and, conditioned on the outcome of a diagnosis procedure (30), setting the device to an alert signal issue state (208) as a function of the outcome of said comparison. The diagnosis procedure comprises computing a set of parameters indicative of the state of the gas sensor circuit, and classifying the gas sensor circuit in one of a first, a second and a third class based on the parameters. As a result of the gas sensor circuit being in the first class, setting the device to said alert signal issue state (208) is disabled. As a result of the gas sensor circuit being in the second class, a sensitivity correction procedure of the gas sensor circuit is triggered and the diagnosis procedure (30) is repeated. As a result of the gas sensor circuit being in said third class, setting the device to said alert signal issue state (208) is enabled.