At What BAC Will I Fail the Interlock Test?

This is a really important question. Knowing at what BAC you will fail the interlock test is critical to passing the test, and complying with the program rules. And of course, full compliance with your state’s restricted driving program will mean you regain full, unrestricted driving privileges sooner.

But the answer to this question is not the same for everyone. The answer depends on what state you live in. But generally, the BAC (blood alcohol content) at which you will fail the test is between .02 and .025. An average person will have that BAC after having one drink in the last ten hours. Wow!

So if you’re thinking you can go out partying into the wee hours and still drive to work in the morning, think again. Depending on your weight, if you were eating, and how much you had to drink, it may take up to 24 hours for alcohol to completely leave your bloodstream.

Ignition Interlock BAC by State

All 50 states have ignition interlock programs, but as we said, the BAC at which you fail the interlock test may be different depending on where you live. Most states refer to this as the “alcohol set point.” Many states have determined their own alcohol set points, while others follow the National Highway Transportation Safety Administration (NHTSA) recommendation of .02-.025, which is set out in the model specifications for breath alcohol ignition interlock devices. New Jersey has the highest alcohol set point, at .05. For any state where it says “unclear” that means the state law does not spell it out.

  1. Alabama .02
  2. Alaska .025
  3. Arizona .02
  4. Arkansas .025
  5. California .03
  6. Colorado .025
  7. Connecticut .025
  8. Delaware .05
  9. Florida .025
  10. Georgia .02 or a limit set by the court
  11. Hawaii .02
  12. Idaho .025
  13. Illinois .025
  14. Indiana .02
  15. Iowa .025
  16. Kansas .03
  17. Kentucky .02
  18. Louisiana .03
  19. Maine .025
  20. Maryland .025
  21. Massachusetts .02
  22. Michigan .02
  23. Minnesota .02
  24. Mississippi .02
  25. Missouri .02
  26. Montana .025
  27. Nebraska .03
  28. Nevada .02
  29. New Hampshire .02
  30. New Jersey .05
  31. New Mexico .025
  32. New York .025
  33. North Carolina .00 to .04 depending on your violation
  34. North Dakota .00 to .025 depending on circumstances
  35. Ohio .025
  36. Oklahoma .02
  37. Oregon .02
  38. Pennsylvania .025
  39. Rhode Island
  40. South Carolina .02
  41. South Dakota unclear
  42. Tennessee .02
  43. Texas .03
  44. Utah unclear
  45. Vermont .02
  46. Virginia .02
  47. Washington .025
  48. West Virginia .025
  49. Wisconsin .02
  50. Wyoming .025

Ignition Interlock Devices Are Highly Accurate

You should know going in that ignition interlock devices are highly accurate. ALCOLOCK ignition interlock devices use what’s known as alcohol fuel cell sensor technology, meaning the device is set up to detect alcohol, and ignore other things like cigarette smoke or acetone. To get the best results, don’t eat, drink, or smoke within 10 minutes of submitting a breath sample. And consider rinsing your mouth out with water before taking the test.

When you give an appropriate breath sample, the device can detect the slightest amount of alcohol. If you have alcohol on your breath, but not enough to go over the alcohol set point for your state, the device will display WARNING but will not fail you.

Anti-Tampering and Anti-Cheating Features

Your ignition interlock device is also equipped with anti-tampering features and warning labels. Attempting to tamper with, or remove the device is a major program violation, and will result in a Permanent Lockout. Your device may also be equipped with a camera, which takes a picture each time you submit a breath sample. This ensures you don’t try and have someone else take the breath test for you.

How to Avoid Failing the Interlock Test

So to review, you can avoid failing the interlock test by not attempting to drink and drive. It really is that simple. A beer or a glass of wine with dinner is probably OK if you’re not going anywhere until morning. But other than that, you should consider abstaining for the duration of your ignition interlock program. Doing so ensures you will complete the restricted driving program in the shortest amount of time.

Failing several startup tests in a limited time, or failing a rolling retest can have serious consequences, including:

  • Extension of the length of time you are required to have the IID installed
  • Having to fulfill your full license suspension
  • Revocation of probation
  • Fines
  • Possible jail time

ALCOLOCK wants to help you successfully complete your restricted driving program, and get your life back to normal.

Schedule Your Ignition Interlock Device Installation

To schedule your interlock device installation with ALCOLOCK, simply call the service location most convenient to you. Or you can call ALCOLOCK directly at (866) 700-9300. We have ignition interlock device installation locations all across the country.  When you call, please have the restricted driving program paperwork you got from the state. Once we confirm your eligibility for your state’s ignition interlock program, we can usually get your installation scheduled within two days of your call.

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