How Long After You Stop Drinking Can You Pass an Ignition Interlock Device Test?

The short answer, as they say in relationship status, is it’s complicated. How long after you stop drinking before you can pass an ignition interlock device test depends on your gender, your weight, how much you have had to drink, how long you’ve been drinking, if you were drinking on an empty stomach, and more.

It all has to do with how the human body, in this case, yours, processes alcohol.

Your Body and Alcohol

When you have a glass of wine with dinner, a few beers while watching the game, or you party late into the wee hours and lost count of how many drinks you had, the alcohol affects your body. You know when you feel tipsy, or even when you pass out. But there’s a scientific reason for that.

When you consume alcohol, it almost immediately enters your bloodstream. As a result, the alcohol goes straight to your brain, which is why you may have slower reflexes, louder speech, or be off-balance. Your liver does the work of processing the alcohol or metabolizing it. In general, a man’s liver can metabolize 1 standard drink per hour. And drinking water or coffee will not speed up that process.

A Standard Drink

The National Institute on Alcohol Abuse and Alcoholism defines a standard drink as:

  • 12 fl oz of regular beer (Bottle or can)
  • 8-9 fl oz of malt liquor
  • 5 fl oz of wine
  • 5 fl oz shot of distilled spirits (whiskey, gin, rum, tequila, vodka, etc.)

Each of these drinks has approximately 14 grams of pure alcohol. The percentage of alcohol is higher in wine than it is in beer, and higher in distilled spirits (hard liquor) than it is in wine. That’s why one standard glass of wine has as much alcohol as more than two beers. And if you drink wine from an especially large glass, you may be having two drinks in one glass.

How Long One Standard Drink Stays in Your System

Alcohol sticks around longer than you might think. Just because your liver has metabolized one drink in one hour, it doesn’t mean the alcohol is gone from your system. After your last drink, alcohol stays in your system:

  • In Your Blood: Up to 6 hours
  • On Your Breath: 12-24 Hours
  • In Your Urine: 12-24 Hours
  • In Your Saliva: 12-24 Hours
  • In Your Hair: 90 Days

So the answer to the question, How long after you stop drinking can you pass an ignition interlock device test? is anywhere from 12 to 24 hours after your last drink. So really, you shouldn’t plan to drive unless it’s been at least 12 hours since your last drink. That means if you were up until the wee hours of the morning partying, you probably shouldn’t try to drive to work, even if you feel fine. Call Lyft or Uber, or carpool with a coworker.

If you had wine with dinner, don’t plan to drive anywhere until the next morning. You get the idea.

Ignition Interlock Devices Are Sensitive

Ignition interlock devices are designed to detect a very small amount of alcohol. And in most states, the blood alcohol content (BAC) level at which the device would say you failed the test is only 0.02%. That’s one drink. And if the device detects alcohol at a lower level, you will be allowed to start the car, but the device will give you a warning, which will be recorded.

So there you have it. While your restricted driving program doesn’t require you to stop drinking, abstaining before driving will ensure you pass the ignition interlock device test every time. And that will allow you to finish the program in the least amount of time.

Ignition Interlock Device Installation Is Easy with ALCOLOCK

ALCOLOCK provides fast and affordable ignition interlock device installation at service centers all across the country. If you need to get an IID installed, call the service center most convenient to you, or call ALCOLOCK at (866) 700-9300 to set up your installation appointment. Be prepared, and have your DMV/DOT paperwork with you. We’ll need some of that information.

Things to Know About Your IID Installation Appointment

You’ll need to have someone drive you and your vehicle to your ignition interlock installation appointment. If someone else will be driving the car while you have to have the IID in your car, it would make sense for them to be the person to drive you. We’ll show you and any other driver how to use the device, and what all of the sounds and messages mean. We will also give you an owner’s manual to keep in your vehicle for the duration of your restricted driving program.

Scheduling Your First Service Visit

Before you leave your installation appointment, your technician will schedule your first mandated service visit. Service visits are usually every 30 days, but your state paperwork will give you specifics. At each service visit, the technician will transmit all of the information the device has recorded to your monitoring agency. Your IID technician will also recalibrate the device as needed, and then schedule your next appointment. For your convenience, the device will give you reminders of an upcoming appointment.

At ALCOLOCK, our goal is to make it easy to complete your restricted driving program. We look forward to serving you!

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