Do Ignition Interlock Devices Only Detect Alcohol?

Ignition interlock devices (IIDs) are designed to keep people from driving drunk. Specifically, an IID is designed to prevent you from starting your car if your blood alcohol concentration is above the state-permissible level (generally .02-.025). The full name that the National Highway Transportation Safety Administration (NHTSA) uses is Breath Alcohol Ignition Interlock Devices (BAIIDs).

The NHTSA Model Specifications for BAIIDs lay out a lot of information about how reliably accurate the devices must be in detecting alcohol, and how they must not result in a false positive, So yes. When you blow into an ignition interlock device, the only substance the device will detect in that breath sample is alcohol. It ignores anything else on your breath. If there is alcohol on your breath, it will compute the blood alcohol content (BAC) based on your breath sample. It will then either indicate that you passed the test or failed the test. It may also issue a warning that while you did not fail the test (blow above the set level), it detected a smaller amount of alcohol.

If you pass the test, you can start the car. If you fail the test, the device locks you out from starting the car. Depending on your state, you will have another chance to blow a clean sample in a few minutes.

But the Camera May Detect Evidence of Impairment

So while the ignition interlock device breath sample cannot detect cigarette smoke, marijuana, or other drugs in your system, if your device is camera-equipped, you should be aware of that fact.

More and more state ignition interlock laws are now requiring that the interlock devices used in their restricted driving programs be camera-equipped. This is in order to ensure that you are not having someone else take the breath test for you. A camera equipped device takes a quick snapshot of you each time you submit a breath sample — both in a start-up test and in a rolling retest.

So if you’ve been smoking weed, there may be a cloud of smoke in the car. If you’ve been using certain drugs, your pupils may be dilated, or be reduced to pinpoints. All of these snapshots and breath test results are recorded on your device. That data is then transmitted to your monitoring agency either in real-time, or at regular service visits. Rest assured, someone at the DMV or in the court system is reviewing those snapshots. If they suspect you have been driving while impaired, even if they didn’t catch you in the act, they may use the pictures as a reason to order a drug test. Depending on the results of that drug test, you could face additional charges.

If You Get Pulled Over

If you get pulled over for any reason, and an officer suspects you are impaired, they may ask you to blow into the IID and check the results. They may also use their own breathalyzer. If both of those tests are negative, the officer may administer a number of other roadside tests designed to detect drug use. If you are charged with driving under the influence of drugs, that will be a major violation of your restricted driving program. So not only could you face criminal charges, but you could lose all of your driving privileges again.

So please, don’t drive impaired, for your safety, and the safety of everyone else on the road.

Schedule Your Ignition Interlock Device Installation

If you just got an interlock restricted license and you’re ready to get back behind the wheel, ALCOLOCK can help. We offer fast and affordable ignition interlock device installation. We have service centers all across the country. Simply call the service location nearest you to schedule your IID installation. You can also call ALCOLOCK directly at (866) 700-9300. You can save time by having your paperwork handy when you call, as we will need some of that information.

Generally, we can get you an installation appointment for some time during the two days after your call. Remember, you will need to have someone drive you and your vehicle to your appointment, which should take about an hour. That time includes the physical installation of the device, as well as the time it takes for the technician to show you how to use it, and explain what all of the sounds, lights, and messages mean. If someone else will be driving your car while you have the IID installed, we will need to train them to use it as well. And finally, before you go, you will schedule your first service visit. Those usually take about 20 minutes.

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