[Criteria for the validation of forensic breath alcohol tests (results of a specialty meeting of the Society against Alcohol in Road Traffic e.V.)].

According to the conception developed in the Federal Health Office a forensic breath-alcohol determination requires two independent measurements of ethanol concentration received by two measuring systems of different analytical specify in order to detect interfering substances. In addition to the two values of the breath-alcohol concentration two values of the exhaled volume, the duration of exhalation and the final breath temperature were obtained. According to the recommendations of the Organisation Internationale de Métrologie Légale (OIML) valid measurements require two breath alcohol values. The difference between the two values must not exceed prescribed limits. Furthermore the other pairs of measured values can be used for a judgement of the measuring procedure. Criteria were derived from the results of tests in practice. By application of these criteria the reliability of breath-alcohol determination is increased and an influence intentioned by the subject on measured values can be avoided.