A study of some factors affecting the accuracy of the breathalyzer.

Abstract

The student of Breathalyzer literature finds most writers agree that the accuracy of the instrument is unaffected by changes in a number of instrumental and environmental factors, provided the variations are within certain specified limits. However, there is little published data supporting these statements. For this reason, and because one of the authors frequently appears in court as an expert witness in cases where the results of breath tests are presented in evidence, it was decided to study these factors at first hand. The results of these investigations are given as follows: variation in composition of ampoule solution; disappearance of mouth alcohol; effect of ampoule temperature; ampoule solution volume; reaction with various volatiles; accuracy of breathalyzer scale; and, reproducibility.