(FR2718240-A1)      The identification of a gas amongst several known gases in a gaseous mixt. based on air comprises placing a single catalytic transducer (11) in the mixt.. The transducer is first of all brought to a lower threshold temp. at which the oxidisable gas undergoes little or no oxidn. and a first reading of a degree characteristic of the thermal mode of the transducer is stored. The temp. is then raised to a higher threshold value at which a sec. reading, characterising the higher temp., is stored representing a stage at which significant oxidn. is occurring at the contact of the transduced. Following a pre-determn. rule a response signal characteristic of the thermal systems is derived. The transducer is then allowed to cool below the lower threshold temp. and the preceding operations are repeated cyclically.    USE -   Used in a methanometer with corrected readings conforming to the European meterological standard (EN 50055), an explosimeter conforming to EN 50057, a multi-gas unit conforming to EN 50055 and 50-057 identifying the gas measured, and a selective methanometer.    ADVANTAGE -   The process enables the characteristics of a gaseous medium, mainly air and a lesser part of at least one oxidisable gas to be determined, using a single catalytic transducer (without a compensating element). The vol. concn. (titre) of the oxidisable gas(es) may be determined. Using the single transducer, the 'uncertainty of measurement' of certain gases (partic. methane) can be removed. A simultaneous measurement of the concn. of several given oxidisable gases can be determined. The process measures the response of the single transducer to a heating phase of short duration, then from there responses of the vol. titre can be measured, 'uncertainty of measurement' removed and/or the gas (or gases) identified.    (JP8043341-A)      The identification of a gas amongst several known gases in a gaseous mixt. based on air comprises placing a single catalytic transducer (11) in the mixt.. The transducer is first of all brought to a lower threshold temp. at which the oxidisable gas undergoes little or no oxidn. and a first reading of a degree characteristic of the thermal mode of the transducer is stored. The temp. is then raised to a higher threshold value at which a sec. reading, characterising the higher temp., is stored representing a stage at which significant oxidn. is occurring at the contact of the transduced. Following a pre-determn. rule a response signal characteristic of the thermal systems is derived. The transducer is then allowed to cool below the lower threshold temp. and the preceding operations are repeated cyclically.    USE -   Used in a methanometer with corrected readings conforming to the European meterological standard (EN 50055), an explosimeter conforming to EN 50057, a multi-gas unit conforming to EN 50055 and 50-057 identifying the gas measured, and a selective methanometer.    ADVANTAGE -   The process enables the characteristics of a gaseous medium, mainly air and a lesser part of at least one oxidisable gas to be determined, using a single catalytic transducer (without a compensating element). The vol. concn. (titre) of the oxidisable gas(es) may be determined. Using the single transducer, the 'uncertainty of measurement' of certain gases (partic. methane) can be removed. A simultaneous measurement of the concn. of several given oxidisable gases can be determined. The process measures the response of the single transducer to a heating phase of short duration, then from there responses of the vol. titre can be measured, 'uncertainty of measurement' removed and/or the gas (or gases) identified.    (US5709792-A)      The identification of a gas amongst several known gases in a gaseous mixt. based on air comprises placing a single catalytic transducer (11) in the mixt.. The transducer is first of all brought to a lower threshold temp. at which the oxidisable gas undergoes little or no oxidn. and a first reading of a degree characteristic of the thermal mode of the transducer is stored. The temp. is then raised to a higher threshold value at which a sec. reading, characterising the higher temp., is stored representing a stage at which significant oxidn. is occurring at the contact of the transduced. Following a pre-determn. rule a response signal characteristic of the thermal systems is derived. The transducer is then allowed to cool below the lower threshold temp. and the preceding operations are repeated cyclically.    USE -   Used in a methanometer with corrected readings conforming to the European meterological standard (EN 50055), an explosimeter conforming to EN 50057, a multi-gas unit conforming to EN 50055 and 50-057 identifying the gas measured, and a selective methanometer.    ADVANTAGE -   The process enables the characteristics of a gaseous medium, mainly air and a lesser part of at least one oxidisable gas to be determined, using a single catalytic transducer (without a compensating element). The vol. concn. (titre) of the oxidisable gas(es) may be determined. Using the single transducer, the 'uncertainty of measurement' of certain gases (partic. methane) can be removed. A simultaneous measurement of the concn. of several given oxidisable gases can be determined. The process measures the response of the single transducer to a heating phase of short duration, then from there responses of the vol. titre can be measured, 'uncertainty of measurement' removed and/or the gas (or gases) identified.    (EP675357-B1)      The identification of a gas amongst several known gases in a gaseous mixt. based on air comprises placing a single catalytic transducer (11) in the mixt.. The transducer is first of all brought to a lower threshold temp. at which the oxidisable gas undergoes little or no oxidn. and a first reading of a degree characteristic of the thermal mode of the transducer is stored. The temp. is then raised to a higher threshold value at which a sec. reading, characterising the higher temp., is stored representing a stage at which significant oxidn. is occurring at the contact of the transduced. Following a pre-determn. rule a response signal characteristic of the thermal systems is derived. The transducer is then allowed to cool below the lower threshold temp. and the preceding operations are repeated cyclically.    USE -   Used in a methanometer with corrected readings conforming to the European meterological standard (EN 50055), an explosimeter conforming to EN 50057, a multi-gas unit conforming to EN 50055 and 50-057 identifying the gas measured, and a selective methanometer.    ADVANTAGE -   The process enables the characteristics of a gaseous medium, mainly air and a lesser part of at least one oxidisable gas to be determined, using a single catalytic transducer (without a compensating element). The vol. concn. (titre) of the oxidisable gas(es) may be determined. Using the single transducer, the 'uncertainty of measurement' of certain gases (partic. methane) can be removed. A simultaneous measurement of the concn. of several given oxidisable gases can be determined. The process measures the response of the single transducer to a heating phase of short duration, then from there responses of the vol. titre can be measured, 'uncertainty of measurement' removed and/or the gas (or gases) identified.