[Temperature measurement in breath alcohol analysis].

Breath-alcohol concentration determined in expired alveolar air depends even at equal blood concentration on the temperature of the breath while leaving the subject's mouth. By using a two-stage simulator it is possible to simulate the physiological reality and to examine the measuring conditions of the temperature. The results show the essential influence of the mouthpieces and the environmental temperature on the measured values. Deviations especially appear at low environmental temperature. To reduce systematic deviations an electrically heated support of the temperature probe was developed which diminishes the influence of the mouthpieces to -0.3 degree centigrade. This device almost eliminates the influence of temperature of the environment.