With the change in drunk driving legislation, the ability to predict an individual's Blood Alcohol Concentration (BAC) becomes increasingly important. In an attempt to reduce the number of drunk drivers on the road, state agencies, as well as public and private groups, have been distributing cards and calculators designed to allow the average person to predict his or her BAC. Unfortunately, these cards and calculators are based on old data, and often provide incorrect information. This places individuals attempting to be responsible drinkers at risk of arrest, despite their good intentions.

This paper reviews the current information on how various factors affect predicted BAC. Factors discussed include height, weight, age, food intake, other drug interactions, and menstrual cycle. The data were derived from reviews of the literature, interviews with individuals currently conducting research in the field, and data collected by the author in several experiments. This paper concludes with a discussion of the major factors affecting BAC prediction, and how these factors may be implemented in future self-prediction devices.