The PAS III is a high speed breath alcohol screening instrument that doubles as a high-intensity flashlight. The passive alcohol sensor is designed to offer a noninvasive method for alcohol detection. The PAS III uses a small, silent pump that draws an air sample through a fuel cell, generating a small electrical current in the presence of alcohol vapor. This current is amplified electronically and is displayed on a multicolored bar graph. The number of bars lit in the display indicates the approximate alcohol concentration in the air sample. The PAS III is only an initial test to help determine whether alcohol is present. Officers should then decide whether to use other field sobriety tests to assist in their assessment of intoxication. The PAS III allows officers to check motorists for possible alcohol violations expeditiously during road checks; therefore, the officer spends less time with the motorist, and the motorist experiences minimal delay and inconvenience. The PAS III can be used to detect alcohol on a person's breath, check for the presence of open containers, and could prove useful for School Resource Officers or other officers who may be required to detect alcohol on minors. Techniques for using the PAS III are described.