APPARATUS FOR GAS ANALYSIS

摘要

A breath alcohol testing instrument comprises a breathing tube (10) connected to an instrument (15) for detecting alcohol, including a sampling system comprising a spring-loaded piston (30) arranged to draw a gas sample into a sampling chamber (21) in contact with an electrochemical fuel cell (20). A pressure sensor (52) detects a predetermined breath flow rate and starts a timer (53) which after a predetermined interval actuates a solenoid (40) to release the sampler. If the suspect interrupts normal breath flow the system does not "abort". The solenoid (40) is still actuated automatically either immediately when the pressure sensor (52) indicates a predetermined drop in pressure or after the preselected time interval. Simultaneously a "test fail" signal is generated (55) and applied to a warning signal generator (56) which actuates a visible or audible warning sign to indicate a non-standard test result.