Patent ID: 7377352

Claim:
A vehicle ignition interlock system, comprising: a breath analyzer located within a vehicle, wherein the breath analyzer comprises an alcohol sensor that is configured to detect breath alcohol levels of an operator of the vehicle, and a mouth contamination sensor that is configured to distinguish between contaminants in the mouth of a vehicle operator and alcohol contained within a deep lung breath sample; and a controller operably connected to the alcohol sensor, to the mouth contamination sensor, and to an ignition system of the vehicle, wherein the controller is configured to compare detected breath alcohol levels of the vehicle operator with a threshold value, wherein the controller is configured to prevent vehicle ignition if a breath alcohol level detected by the breath analyzer is greater than or equal to the threshold value, and wherein the controller is configured to trigger a breath alcohol retest of the vehicle operator via the breath analyzer in response to detecting the presence of a contaminant within the mouth of the vehicle operator.