A breath alcohol ignition interlock device (BAIID) is a device that prevents a vehicle from starting if the driver has a breath alcohol concentration (BrAC) above a preset limit. The device requires the driver to provide a breath sample before starting the engine, and periodically during the drive. The device measures the amount of alcohol in the breath sample and compares it to the limit set by the authority that installed the device. If the BrAC is above the limit, the device will lock the ignition and prevent the vehicle from starting or continuing to operate.
