What is an Ignition Interlock Device

According to the Arizona Department of Transportation's Motor Vehicle Division, an ignition interlock device is:

...slightly larger than a cell phone and is wired to your vehicle's ignition.  The device...requires your breath sample before the engine will start.  If the ignition interlock device detects alcohol on your breath, the engine will not start.  As you drive, you are periodically required to provide breath samples to ensure the continued absence of alcohol in your system.

When the Arizona Certified Ignition Interlock Program requires the uses of a Certified Ignition Interlock Device (CIID) following a period of driver suspension / revocation, you must have one installed by a company that is authorized by the Department of Motor Vehicles (MVD).  Moreover, the MVD will monitor drivers required to have the device installed.  A person will also receive a replacement driver's license with "Ignition Interlock" written on it.

After the device is installed, the CIID must be calibrated and inspected by a certified installer every thirty (30) days for the first three months and then every other month for the duration of the installation requirement.  Drivers who do not comply with the CIID requirements are reported to MVD and may have the period for use extended.