The blood alcohol content of an individual suspected of driving while intoxicated is often measured through the analysis of a breath sample using an evidential breath tester (EBT). Two factors determine the ability of an EBT to provide an accurate analysis of alcohol concentration: (a) the capability of obtaining an appropriate breath sample, and (b) the inherent accuracy of the analytical instrument. This report characterizes the relevant breath parameters and describes a breath alcohol sample simulator (BASS) that was developed as a means of reproducing accurate equivalents of human breath. The report discusses measurements made on human subjects to establish values for parameters the BASS must accommodate, and to demonstrate the validity of the BASS as a replacement for human drinking subjects with different levels of alcohol content and a range of physiological characteristics.
Abstract