Determination of ethyl alcohol in human biological material is the most common forsenic chemical examination, the majority of such determinations being performed in connection with investigations to establish the presence or absence of alcoholic influence in operators of motor vehicles. Utilization of alcohol determinations by law enforcement agencies in the United States continues to increase rapidly as demonstrated by an increase of 220% in the number of cities employing chemical tests for alcoholic influence during the last 4 years1. Twenty-three states now have chemical test legislation. Because of the rapidly expanding employment of forensic alcohol determinations, it seemed pertinent to examine some practical laboratory aspects of such tests in the light of our experience with approximately 25,000 such examinations during the past ten years
