Your Car Breathalyzer and the Air You Breathe

Have you ever wondered how a car breathalyzer works? Or what happens if you try to fool the system? Ignition interlocks (car breathalyzers) are fairly simple in theory but use sophisticated software and hardware to prevent tampering. All interlocks that are ordered by a court must be installed by a trained and certified installer. The system powers on with the vehicle, but without blowing into the car breathalyzer, the engine will not start. Most car breathalyzers will monitor what the blood alcohol concentration (BAC) is, as well as the start and stops the vehicle makes. For DUI offenders, this data is sent to the courts after the information is transmitted during your appointment. If your breath registers above the allowed BAC, your engine will not start.

Car breathalyzers often bring up questions about breath and air. For instance:

When you have an ailment that takes your breath away, like asthma or chronic obstructive pulmonary disease (COPD), life can be pretty difficult. When you also have a drunk driving conviction and a car breathalyzer (ignition interlock), you probably think you will not be able to fill your lungs enough to remain compliant. Normally an ignition interlock requires a certain amount of pressure in order for your test results to be considered accurate. If you have asthma, COPD or any other health issue that could prevent you from breathing into the device at the required pressure, your device can be adjusted accordingly. Just contact your ignition interlock service provider.

Attempting to fool the device by blowing into balloons and keep them saved in the car simply will not work. The ignition interlock device wants to reassure itself that you’re human, so it will ask you to hum to prove it. Anti-circumvention techniques allow the machine to refuse phony breath samples – the device can detect instantly when an actual human breath is not being blown into it. Even if a person is taking medicine that has alcohol in its ingredients, or has used mouthwash beforehand, the machine will indicate a presence of alcohol over the preset limit and log in a fail.

There’s a reason ignition interlocks are extremely difficult, if not impossible, to fool: the stakes are so high. Often these devices are all that lie between a drunk driver and the innocent people on the road. Their job is to save lives, and statistics show they’ve been doing just that wherever they are required by law.