Confirmation of Ethanol Compressed Gas Standard Concentrations by an NIST-Traceable, Absolute Chemical Method and Comparison with Wet Breath Alcohol Simulators

This study compares compressed-gas Ethanol Breath Standards (EBS®) with wet simulators as calibration standards for breath alcohol analyzers. After reviewing the technical basis and traceability for the two calibration sources, new analytical data verifying the ethanol content of EBS gas are presented. Based on collection of ethanol in an impinger and titration using a modified California Department of Health method, the data confirm the alcohol content of EBS compressed gas standards by an absolute, wet chemical method. These results establish the concentration accuracy and the NIST traceability of the EBS gas by two independent methods, gas chromatographic analysis traceable to NIST standards and the new wet chemical method. Effluent gas from a wet simulator standard is then analyzed by the wet method to show its equivalence with EBS gas.