| 摘要 |
A device and method for determining the alcohol content of a test person's breath comprising, a breathing sample line adapted to receive the test person's breath, a valve in the sample line for closing a flow of breath therein, a test chamber connected to the sample line downstream of the valve for receiving and testing the breath and a pressure sensing transducer connected to the sample line upstream of the valve for sensing the attainment of a predetermined pressure in the sample line. A clock is connected to the pressure sensing transducer and begins to operate when the preselected pressure has been obtained. The clock is connected to the valve and opens the valve only after the expiration of a preselected time period where the preselected pressure has been maintained throughout the period. |
