Rules Governing Ignition Interlock
An Ignition Interlock Device, referred to as an "IID," is an after-market device which is installed in a vehicle. The IID is connected to the starter or ignition, or other onboard computer system of a vehicle. The device prevents a driver from operating the vehicle if the driver has been drinking. Before starting the vehicle, a driver must blow into the device; if the driver's BAC is at or over a pre-set limit (0.02 in Vermont) the IID will not allow the vehicle to start. Once the vehicle is started, at random times during the operation of the vehicle, the device will prompt the driver to provide another breath sample, referred to as "random retests." If the breath sample is not provided, or if the breath sample is at or exceeds a BAC of 0.02, the IID will log the event as a failure, and will then signal the vehicle to begin flashing the lights and sounding the horn. This will continue until the vehicle is turned off, or a clean breath sample has been provided.