What is a DUI Interlock Device?

Updated on 09/20/2023 / Under

A DUI interlock device is a breathalyzer in a car. It stops a person convicted of DUI from driving if they have been drinking. The driver must blow into the alcohol ignition interlock device to check their breath alcohol content before starting the car. If alcohol is detected, the car won't start.

Many states require a breath alcohol ignition interlock device for DUI convictions. The length of the interlock program time varies by state. The device prevents drunk driving offenses and requires sobriety before driving.

If you have questions, about ignition interlock device laws, our Naperville DUI lawyers can help! Call today at (630) 425-0250 for a free consultation!

What a DUI Interlock Device is For?

A DUI interlock device is a breathalyzer installed in your type of vehicle. It requires a breath sample before starting or while driving. If alcohol is detected, the engine won't start or will shut off. The device prevents intoxicated driving by restricting vehicle operation.

a woman blowing into her ignition interlock device to start her car

Courts often mandate the installation and use of an ignition interlock device after a DUI conviction. The duration of installation varies by state, ranging from 6 months to several years before unlimited driving privileges are reinstated.

Types of Ignition Interlock Devices

A DUI interlock device is similar to a breathalyzer and is placed in the vehicles of individuals convicted of DUI. Before starting their car, the driver must blow into the device. If their blood alcohol content level is too high, the vehicle will not start. The device also requires random tests while driving. Failing these tests will result in the engine shutting off.

There are two main types of DUI interlock devices: passive and active.

  • A passive device has additional features and requires breath tests each time the vehicle starts and at random points during the drive. It will also alert the police if a failed test is detected.
  • An active device only requires a breath test when the vehicle is started and does not alert the police, but it will shut off the engine if a failed test is detected.

Functions of an Ignition Interlock Device

A Breath Alcohol Ignition Interlock Device (BAIID) is a limited driving privilege breath-testing device. It stops a vehicle from starting unless the driver provides a breath sample below the legal alcohol limit. Drivers blow into the device before starting their vehicles. If the breath sample exceeds the limit, the vehicle won't start. An alert is sent.

Useful Info: List of Certified BAIID Providers in Illinois

The BAIID also requires random tests while driving. If a failed test is detected, the vehicle shuts off. An alert is sent. Another person's breath sample won't start the vehicle. The device is only calibrated for the assigned user's breath sample.

Installation Process

A DUI interlock device is a breathalyzer installed in a vehicle by an interlock provider that meets ignition interlock compliance standards. An installation appointment is provided by ignition interlock companies. Installation of a DUI interlock device by an ignition interlock provider takes less than an hour and is done by a certified installer.

The first step is connecting the device to the vehicle's ignition system and horn. The installer then calibrates the device for the specific vehicle and secures it in place. Finally, the installer connects the device to a monitoring service for reporting on breath tests and tampering attempts.

Service Centers

A DUI Interlock Device measures alcohol in a person's breath. It is installed in a convicted DUI driver's vehicle. Most states require drivers to visit approved interlock provider service centers for device calibration and maintenance.

a man checking his BAIID to try and drive his vehicle

These centers are usually near major roads and intersections. They offer ignition interlock device installation, calibration, maintenance, and removal services. When visiting a service center, drivers must bring their license and vehicle registration documents.

Breath Sample Requirements

A DUI interlock device is a mechanism that requires individuals to blow into a tube before their vehicle starts. It is used to prevent those convicted of DUI from driving under the influence of alcohol.

The breath sample must meet the preset alcohol concentration level for the device. This threshold is usually 0.02%, but it can be adjusted. If the breath sample exceeds the limit, the vehicle won't start and an alert is sent to the monitoring service.

Random and Rolling Retests

A DUI interlock device is a breathalyzer in a car. It stops the driver from starting or driving until they pass a breath test. The device measures the driver's blood alcohol level before starting the engine. Random retests happen while driving, needing a clean breath sample for the car's movement. Rolling retests also occur, needing breath samples at regular intervals during the drive. Failing any of these tests sends an alert for monitoring and shuts off the vehicle.

Safety Reasons for Installation

A DUI Interlock Device is installed on a vehicle's ignition system to prevent it from starting if the driver's breath alcohol concentration exceeds the limit. It is required by law for those convicted of DUI.

a glass of alcohol next to some car keys and a gavel

The ignition interlock systems help reduce impaired driving and alcohol-related fatalities. It can also be used as a punishment for DUI offenders. Drivers must pass a breathalyzer test before starting their vehicle to deter intoxicated driving.

Motor Vehicle Restriction Periods

A motor vehicle restriction period, or MVRP, is a period when someone is not allowed to drive after being convicted of a DUI. During this period, the person must use a specific device in their vehicle to test their breath before they can start and drive.

If the test shows alcohol above the limit, the vehicle won't start. The length of the restriction period depends on the details of the DUI conviction, usually ranging from six months to two years.

For More Information, Call Naperville DUI Lawyer Today!

A DUI interlock device is a breathalyzer machine in a vehicle. The driver must blow into it before starting the engine. If the BAC is too high, the ignition won't start. Some states require DUI interlock devices for all convicted DUI drivers. Installation duration varies by state.

Contact an experienced Naperville DUI lawyer for guidance if charged with a DUI.