When you have an ignition interlock device, you already have a lot on your mind. More than likely, you were ordered to install the device by the court or through your DMV because of a drunk driving incident and/or conviction. After everything you’ve been through, you may still have questions about using the device. Like, how long your ignition interlock can detect alcohol, or when you can safely use your device after you’ve been drinking.
If you have been drinking alcohol, your ignition interlock will detect it and you will not be able to drive until your blood alcohol concentration (BAC) is under the limit your state requires.
An ignition interlock device is built specifically to keep drunk drivers off the roads, and its ability to stop detecting alcohol isn’t affected by its age or how many times it has been used. How long after drinking an ignition interlock can detect alcohol depends more on the person who was drinking and how much alcohol was consumed. Typically, we rely on the “one drink per hour” rule to calculate how long it takes to have a clean BAC reading, but that isn’t always accurate. You have to take into consideration your gender, your weight and other BAC factors. Plus, even if your BAC is low, you may still be impaired due to medications you are taking or the effects of mixers like diet sodas or energy drinks.
When it comes down to it, using your ignition interlock after you’ve been drinking will probably just lead to more trouble. You do have other options: instead of the worry and frustration, just plan for a safe ride home if you’ve been drinking, even if you have an ignition interlock device. That way, you know you’ll have time to sober up and won’t chance any violations or further consequences.