What Is an Ignition Interlock Device? Cost, Requirements, and FAQs

One of the consequences of a DUI is having your license suspended. Not being able to drive to work or social events (even if you’re not drinking) can negatively affect your life. It also leads many people to commit another crime: driving with a suspended license.

This is why Oklahoma allows those who have been charged with or convicted of a DUI to get an ignition interlock device (IID) in their vehicle. But it’s important to understand what an ignition interlock device is, how it works, and what you need to do to get your license – and life – back.

What Is an Ignition Interlock Device?

An ignition interlock device is a small device that’s installed in your car and controls whether it will start based on your blood alcohol content (BAC). When you want to start the vehicle, you blow into the device and it measures your BAC. If it detects alcohol, it will disable your car so that it won’t start. Then it will log the failure in its system.

An IID can also require you to blow into the device at random times while you’re actually driving. Usually it will require what’s called a “rolling retest” about 5 to 15 minutes after you start the car. If it detects alcohol, it will trigger an alarm and you’ll have to pull over. Again, this will go into the system.

How Does an IID Work?

Ignition interlock devices prevent your car from starting by blocking the signal from the ignition to the starter, which is a small motor powered by the battery. Once it registers a clean breath test, it will allow the signal through. If you fail the test, the signal stays blocked.

When it comes to measuring your BAC, an ignition interlock device is essentially the same thing as a breathalyzer test you might take when you’re pulled over for a DUI. They use fuel cell technology, which causes a chemical reaction to occur if you have alcohol on your breath. This reaction produces an electrical current that the machine reads and shows on the screen as a number: your BAC.

Can I Drink at All with an IID?

The safe answer to this question is “no”: Ignition interlock devices can detect very small amounts of alcohol. In Oklahoma, IIDs are set to detect a BAC of 0.025 or above. This is less than the legal limit for a DUI, which is 0.08, and even a DWI, which is 0.06. According to BAC level charts, most women reach a BAC of more than 0.025 after just one drink, or even less. Depending on weight, some men will, too. Your BAC also depends on your body fat content, how much you ate that day, and more. It’s best not to risk it.

Does an IID Detect Drugs?

No, ignition interlock devices won’t detect drugs, including marijuana. They’re only designed to measure your BAC – the chemical reaction that’s required won’t happen with other substances. But again, you shouldn’t take this risk. If you get a DUI-Drugs, it will count as your second DUI, which means it will be a felony charge. You’ll end up with more consequences that just aren’t worth it.

When Do I Have to Install an Ignition Interlock Device?

In Oklahoma, if your license is suspended because of a DUI, you’ll have to enroll in the Impaired Driving Accountability Program (IDAP), which requires that you install an ignition interlock device in your vehicle. If you don’t want to enroll in IDAP, you can try appealing your license suspension. However, if your appeal is denied or you’re convicted in your criminal case, which is a separate charge, you’ll still have to install an IID and complete IDAP.

There’s also nothing stopping you from voluntarily installing an IID in your car or the car of a loved one. People sometimes do this if they’re a recovering alcoholic or they want to make sure their spouse or teenager doesn’t drive drunk. The installation process is the same in these cases. The only difference is that you’re not enrolled in a program, so your IID isn’t overseen by the state.

How Much Does an Ignition Interlock Device Cost?

An ignition interlock device costs about $75 to install, plus $75 per month to maintain. You might also pay a removal fee. The state of Oklahoma doesn’t regulate the exact cost of an IID: the manufacturers and installers set the pricing. However, they do have to send their fees to the Oklahoma Board of Tests, and they’re not allowed to charge different fees than what’s on record with the Board. That makes it easy to check and compare pricing from different providers.

Keep in mind there’s also a $150 fee to enroll in IDAP and a fee to reinstate your license with the DMV when you complete the program. All of this adds to the high cost of a DUI.

Can I Remove an Ignition Interlock Device?

No. If you’re enrolled in IDAP, the only way to remove an ignition interlock device is to complete the program and reinstate your license. Then you can have it professionally removed. While you may be able to physically remove the device yourself, it will notify your IID provider – and therefore the state of Oklahoma – that you’ve tampered with it.

This is one of the worst interlock violations you can get, and you’ll almost certainly have to keep the IID in your car for even longer as a punishment. The additional time is usually one-third of the original time period. So if your IID agreement was for 6 months, you’ll add another 2 months. If it was for 1 year, you’ll add 4 months. And if you were supposed to have the IID for 3 years, you could add another whole year onto your agreement. Again, it’s just not worth it.

The Bottom Line

Most people end up with an ignition interlock device as a result of a DUI. Oklahoma’s IID requirement may seem inconvenient, but it’s better than the alternative: not driving at all. As you navigate the DUI process, your attorney can help you understand the state’s IDAP and IID requirements. Still wondering whether you should get an IID or how it might affect your case? Contact us today for a free case evaluation.