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      Intoxalock Ignition Interlock Device

      What is a Car Breathalyzer?

      Car Breathalyzers for Responsible Driving

      A breathalyzer for car ignition (also known as an ignition interlock device, IID, BAIID, car breathalyzer, or interlock system) is a device that attaches to the starter of your vehicle and requires you to submit breath samples in order to start your vehicle. The breath samples taken by the IID will measure your breath alcohol concentration (BrAC) and allow you to start your vehicle if you pass the car breathalyzer test.

      Depending on the state you are required to install your ignition interlock system in, the amount of BrAC that prevents your car breathalyzer from starting your vehicle will vary. For more information on what are the ignition interlock device requirements in your state, visit our state requirements page.

      How Does a Car Breathalyzer Work?

      So, how does a car breathalyzer work? In order to start their vehicle, people with an Intoxalock interlock or car breathalyzer installed must:

      • Press the button to activate the device.
      • Once the device indicates it is ready, use the blow-inhale-blow breath pattern to submit their breath test
      • Await results. Once they have passed, they will be able to start their vehicle.
      • If they fail the test, they will be unable to start the vehicle until they pass, and the device may lock them out for a time before allowing a retest.
      Watch How To Videos
      A man holding an Intoxalock ignition interlock device, which is installed in their vehicle to measure breath alcohol concentration before the vehicle can start.

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      How Do Car Breathalyzer Retests Work?

      Some may be tempted to try and cheat the car breathalyzer by having a sober friend take the test. However, this can backfire quickly. To ensure continuous sobriety, many states require random car breathalyzer retests during a trip. The process for a retest is the same as the starter test, the only difference being that the car has already been started. The device will warn you before a test is due, to allow time to pull over if needed. Most breathalyzers give you a few minutes to accomplish this. You will use the same blow-inhale-blow breath pattern on each test and retest.

      Facts About Random Retests
      An Intoxalock ignition interlock device laying in the center console of a vehicle.

      How Much Does a Car Breathalyzer Cost?

      The cost of your car breathalyzer will vary based on multiple factors, including the type of vehicle you install the IID device into and the length of time you are required to have it. For more information on the cost and pricing of car breathalyzers, visit our ignition interlock cost page.

      Taking a BrAC Test

      Each ignition interlock provider has different requirements for use. A blow-inhale-blow device, such as an Intoxalock device, requires the tester to blow into the device for three seconds, then inhale for another three seconds and blow into the device again for a final three seconds. Alternatively, some IID devices demand longer testing durations or incorporate different blow patterns, such as requiring the user to hum while blowing.

      Installing Your Breathalyzer for Car Ignition

      Intoxalock Ignition Interlock makes the interlock installation process simple and convenient by offering the most car breathalyzer installation locations nationwide.

      If you are required to install an IID, call 833-905-3484 today to schedule an installation appointment near your home or work.

      Calibrating Your Car Breathalyzer

      Depending on the state you received your offense in, you will be required to get your car breathalyzer calibrated every 30-90 days. A calibration requires going to one of your provider's service centers and having the technicians check to make sure that your interlock device is working correctly.

      Intoxalock Ignition Interlock – A Simple-to-Use One-Button Activated Car Breathalyzer

      Intoxalock simplifies the entire interlock process for you. Here are some of the many reasons why choosing Intoxalock as your IID provider will make your ignition interlock journey feel like a breeze:

      • More installation locations than any other provider
      • Easy-to-use device (one button, no humming)
      • Excellent customer service available 24/7
      A man sitting in the driver's seat of a car, holding an ignition interlock device, ready to perform a breathalyzer test before starting the vehicle.


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      Call Us Anytime at 877-272-5195
      Our state specialists are ready to answer your questions and get you through the process, one step at a time.