What is an ignition interlock device?

An ignition interlock device is specifically designed to prevent a vehicle from starting unless the driver passes a breath alcohol test. It functions as a breathalyzer that is installed in the vehicle, requiring the driver to blow into the device to measure their blood alcohol content (BAC). If the device detects a BAC over a preset limit, the vehicle will not start, effectively preventing impaired driving.

This technology is commonly mandated for individuals who have been convicted of driving under the influence (DUI) or driving while intoxicated (DWI) as part of their rehabilitation and is often used to enhance public safety by keeping impaired drivers off the road. The focus of an ignition interlock is strictly related to alcohol consumption and vehicle operation, which distinguishes it from other types of devices such as car alarms, GPS trackers, or speed limiters that do not address the issue of driving under the influence.