| abstract |
A gas detecting apparatus and method for qualitatively and quantitatively analyzing a gas for a particular constituent depends on sampling of the gas until the level of one constituent can be detected at some predetermined level; then when this level is attained measuring the gas for the presence of another constituent. Measurement of human alcohol content is achieved by first measuring several samples of the CO2 level in the breath and when the CO2 reaches a predetermined minimum level, corresponding to a true lung sample, the apparatus responds and the alcoholic content is measured. A detecting filament bridge configuration measures alcoholic content by catalytic combustion of the alcohol and oxygen over a platinum filament. |