GAS SENSING APPARATUS Russian patent published in 2016 - IPC G01N27/403 

FIELD: measuring equipment.

SUBSTANCE: invention can be used for selectively sensing of concentration of a target gas in polluted ambient air. The invention consists in the fact thatmethod of selective measurement of concentration of a target gas in polluted ambient air comprising the steps of: providing the sensor of the target gas which is sensitive to target gas; providing the first gas flow derived from ambient air, the target gas being substantially removed from the first gas flow; providing a second gas flow derived from the ambient air, substantially, containing the same concentration of target gas that and ambient air; exposing the target gas sensor to the first gas flow, during the first time interval and obtaining from the target gas sensor a first sensor signal (Smf); exposing the target gas sensor to the second gas flow, during the second time interval, not overlapped with the first time interval, and obtain a second output signal (Smu); calculation of difference (SΔ) between first and second output signals; calculation of concentration of target gas from the calculated difference (SΔ) signal.

EFFECT: technical result is design of a target sensor with small size, low power requirements, minimal maintenance requirements over an operational period of at least several years, as well a combination of high sensitivity and high selectivity with respect to a particular target gas or target class of gases.

15 cl, 14 dwg