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IID Device Certification


What happens if I have repair work or a Vermont State Inspection done on my IID equipped vehicle?

We strongly suggest that you notify your installer before performing vehicle maintenance, service or repairs that would involve starting or driving your vehicle or disconnecting the battery.  Your auto repair technician can contact your installer for specific instructions on how to avoid recording erroneous violations.

What happens if I fail the breath test when I try to start my car?

The vehicle will not start and the IID will enter a short lockout period of a few minutes.  This lockout period allows an opportunity for the alcohol to dissipate from the mouth and for you to consider the reason for the failed breath alcohol test, for example; is the failure a result of the use of mouthwash, cough syrup, etc., or as a result of consuming too much alcohol.  The IID will record the failure, which will be noted in the data report.  If you make 3 attempts to start a vehicle with a BAC of .04 or above, your IID requirements will be extended for a period of 3 months.  

What kind of information does the IID record?

The IID collects and stores the information below, which is reported to the Department of Motor Vehicles and the Department of Corrections.  This information is also provided to the Impaired Driver Rehabilitation Program (IDRP).

  • The date and time of any use, or attempted use of a vehicle including a photo of the driving compartment.
  • The date and time of any attempt to tamper, circumvent or bypass the device.
  • The date, time, and alcohol concentration, in grams per 210 liters, of each breath sample provided to the device.
  • The date and time of any malfunctions of the device.
  • The date and time of any failures to provide retest samples.
  • The date and time a “service required” message is issued to the customer by the device.
  • The date any service is performed.
  • The mileage and hours of operation of the vehicle since the previous service was performed.
Does the IID need to be serviced or maintained in any way?

Yes.  Once installed in your vehicle, the IID must be calibrated and inspected by a certified installer, or “swapped out” (if applicable), every 30 days for the duration of the terms and requirements of an RDL.  The inspection is done to make sure the IID is working properly and to detect any issues of non-compliance.  At the time of inspection, the installer will:

  • Review the data recorded in the device’s memory.
  • Inspect the device for indications of tampering.
  • Calibrate the device.
  • Forward data reports to both DMV.
What is an Ignition Interlock Device

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 on-board 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.

I live out-of-state I have to come back to Vermont to take an alcohol treatment program?

If you live in another state you can take an alcohol treatment program in that state. You must contact the Vermont Impaired Driver Rehabilitation Program (IDRP) before enrolling in a program outside of Vermont. Not all alcohol treatment programs are accepted, and you must ensure that you participate in an acceptable program.

Impaired Driver Rehabilitation Program (IDRP)
Vermont Department of Health
108 Cherry Street
Burlington, VT 05401

Phone: 802-651-1574
Fax: 1-866-272-7989

When I went to court no one told me I had to complete an alcohol treatment program ...why is DMV telling me that I'm required to do this?

Vermont law requires that anyone suspended for an alcohol-related offense must complete an alcohol treatment program. The courts generally try to make you aware of this requirement at the time of your hearing, but if even if they fail to tell you about it you must meet this requirement.