What Should I Do if I Get a False Positive Recording When I Blow Into My Ignition Interlock Device?

If you recently got an ignition interlock device (IID) installed in your vehicle, you’re still learning how to use it. Some states may even give you a grace period for the first month or so, until you get the hang of using the device properly. As someone new to the device, you may be asking yourself “What should I do if I get a false positive when I blow into my ignition interlock device?”

First things first. While you may fail the breath test even when you haven’t been drinking, there is no such thing as a false positive on an ignition interlock device. ALCOLOCK and other device manufacturers abide by the National Highway Transportation Safety Administration (NHTSA) model specifications with every IID we manufacture. That means the devices use alcohol fuel cell technology, and are very precise. Our ignition interlock devices are capable of detecting from 0 to 1.00 mg/L of alcohol content, and provide results with an accuracy of plus or minus 0.02 at 0.20 mg/L.

OK, so if it’s not a false positive, why would your IID register a test failure if you haven’t been drinking, and what should you do if that happens? Let’s take a look.

What to Do if You Fail the Test but Haven’t Been Drinking

If the device registers alcohol on your breath, it will consider that a test failure. If you swish your mouth out with water and wait a few minutes, you should be able to submit a clean breath test. If you believe you should not have failed the test, you will want to notify your monitoring agency and your DUI lawyer or probation officer of what happened, as soon as possible. This can protect you from penalties for a program violation. Many states require a permanent lockout if you fail too many tests in a certain time period.

This applies with both the startup test and any rolling retests.

Many Common Items Have Enough Alcohol in Them to Register on Your IID

So we’ve already discussed that your ignition interlock device is highly precise, and highly accurate when it comes to detecting alcohol on your breath. With this in mind, there are some items you may want to avoid eating, drinking, or using for the duration of your ignition interlock program. At the very least, wait 15-20 minutes after consuming one of these items, and rinse your mouth out with water before attempting to submit a breath sample.

  • Mouthwash
  • Breath spray
  • Some cough medicine
  • Menthol cough drops
  • Food with alcohol, such as pasta with Vodka sauce or rum cake
  • Foods with vanilla extract
  • Energy drinks such as Red Bull or Monster

By making it a habit to rinse out your mouth before submitting a breath sample, you can wash away any food particles or alcohol residue. If you truly haven’t been drinking, the alcohol from these products is only in your mouth, and not your system. Rinsing out and waiting 15 minutes will allow you to pass the breath test and be on your way.

And believe it or not, if you use certain hand sanitizers right before submitting a breath test, the device may detect alcohol and register a test failure. To be safe, wait at least five minutes after applying hand sanitizer before picking up the handheld device and submitting a breath sample.

Schedule Your Ignition Interlock Device Installation

ALCOLOCK has hundreds of ignition interlock device installation locations across the country, so if we operate in your state, you’re sure to find one that is convenient to you. Our IIDs are state-approved, and we offer fast and affordable installation and monthly service appointments.

You should plan on having someone drive you and your vehicle to your installation appointment. Once the technician installs the device, you are free to get back behind the wheel. Your installation appointment should take about an hour. That time includes actual installation of the device, where the technician connects it to your vehicle’s starter, calibrating the device to you and teaching you how to use it, as well as scheduling your first monthly maintenance appointment.

At each maintenance appointment, the technician will send the information the device has recorded to your monitoring agency. The technician will also recalibrate the device as needed, and address any questions or concerns you may have.

To schedule your installation, call one of our service providers directly, or call us at 866-700-9300. You can also use our contact form.

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