What Is a Calibration On My Ignition Interlock Device?

One of the questions we get most frequently is “What is a calibration on my ignition interlock device?”

Simply put, calibration is when we adjust, or calibrate, the device to ensure that it is operating at peak performance, with utmost accuracy. When you first get your ignition interlock device (IID) installed, the technician performs a calibration with you, specifically, where you blow into the device, and the technician tweaks the device as necessary to ensure the device registers your breath sample properly.

Calibration of Your Ignition Interlock Device at Service Visits

The National Highway Transportation Safety Administration (NHTSA) ignition interlock device model specifications require all ignition interlock devices (IIDs) to hold a stable calibration for a minimum of 37 days, which includes the 30 day service interval plus a seven day countdown period before a permanent lockout for failure to bring the vehicle in for service. Most devices today have a longer stable calibration period, to accommodate varying service intervals as determined by each state. For instance, some states may have a 60 day service interval because they receive information from the device remotely.

If you’re participating in your state’s ignition interlock program, you know that you are required to bring your vehicle in about once a month (again, this can vary depending on what state you live it) for a service visit. Failure to show up for the required visit is a serious violation of your program, and could result in an extension of the time you are required to have the ignition interlock device (IID)installed, or your removal from the program altogether.

We make it easy for you to remember your monthly calibration and service appointments. Your device will give you a reminder of an upcoming visit. If you fail to come in for calibration and servicing, the device will enter permanent lockout (after a specified time), which means you will have to have your vehicle towed to the service center. Much easier to come in as scheduled!

At each of these appointments, the IID technician performs a calibration on your ignition interlock device. Your IID uses alcohol fuel cell technology to detect alcohol on your breath, even the tiniest amount. But the devices can lose their precision as time goes on, and thus need re-calibration. If the device is not re-calibrated properly, it can result in false readings.

By false readings, rather than a false positive (no such thing), we mean the device might not properly detect alcohol on your breath if the calibration is out of whack. This could mean that you could drink and drive, which would be a serious problem, as the IID is specifically designed to prevent that. Most manufacturers like ALCOLOCK, and state agencies take such false readings very seriously. There have been recent instances where states have suspended IID vendors or even kicked them out of participating in the state ignition interlock program because their devices did not provide accurate readings.

What the Ignition Interlock Device Records

Of course, the main purpose of the ignition interlock device is to prevent you from starting the car if you’ve been drinking. Blow into the device with alcohol on your breath and the IID won’t let you start the car, Blow a clean sample and you start the car. Simple.

But do you know everything your ignition interlock device records? This includes:

  • Your photo each time you give a breath sample if your device is camera-equipped
  • The time and date you take each start up test and rolling retest. The device will also record your location if it is GPS equipped
  • The exact level of alcohol on your breath
  • Whether you passed or failed the test
  • Whether you tried to start the car without taking the startup breath test
  • If you skipped a rolling retest
  • If you continued to drive after failing a rolling retest
  • If you tried to tamper with or circumvent the device
  • And more

In addition to the calibration on your ignition interlock device, at each service appointment, the IID technician downloads all of the information the device has recorded, and makes it available to your monitoring agency. Read the paperwork for your state regarding failed or missed tests, as those results may need to be reported to your state sooner than every 30 days.

Schedule Your Ignition Interlock Device Installation

ALCOLOCK has numerous ignition interlock device installation locations in states 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 will want to have someone drive you and your vehicle to your installation appointment. Once the technician installs the ignition interlock 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.

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

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