Patent ID: 9696294
Date: 2017-07-04
CPC Classifications: A61B,G01N

Claim:
1. A breath alcohol testing device comprising: a housing; a pressure transducer within the housing; an alcohol sensor within the housing; and a sample chamber assembly removably attached to the housing having: (a) an inlet for receiving a breath sample from a test subject; (b) an inlet chamber receiving the breath sample from the inlet and having: (i) a port to the pressure transducer; and (ii) an outlet for the breath sample to flow from the inlet chamber; (c) a sample chamber receiving the breath sample from the outlet of the inlet chamber and having a port to the alcohol sensor; (d) a filter in the port of the sample chamber preventing liquids from entering the alcohol sensor; and (e) a one-way valve in the outlet of the inlet chamber preventing the backflow of gas from the sample chamber into the inlet chamber; wherein the outlet and one-way valve of the inlet chamber create back-pressure during the breath sample that is measured by the pressure transducer.