Breath-alcohol analysis: uses, methods, and some forensic problems--review and opinion

Breath analysis for ethanol, especially in respect to the forensic aspects, has been reviewed. Included are matters dealing with instrumentation, physiological factors involved in the elimination of ethanol via the breath, and, especially, the uncertainties in the calculation of a whole blood concentration of ethanol from the quantity found in breath. We believe that the conversion of a breath quantity to a blood concentration of ethanol, for forensic purposes, should be abandoned and that the offense of driving while under the influence of alcohol should be statutorily defined in terms of the concentration of ethanol found in the breath in jurisdictions employing breath analysis. The breath sample should be obtained and analyzed only with instruments having capabilities which would require some extension of present federal standards for evidential breath-testing devices. Events in early 1975 indicate that implementation of some of these proposals may soon be undertaken.