Are All Ignition Interlock Blow Patterns Alike?

The short answer is “no” not all blow patterns are alike. There are three basic patterns, for the most part, in the interlock industry:

  • Blow and hum
  • Blow, inhale, and blow
  • Straight blow

The blow and hum pattern is the easiest to learn and produces a quality breath sample. So what does that mean to you?

  • Easier to learn means you quickly get more comfortable at taking tests. It will become second nature in no time to get successful results.
  • A successful test means the breath sample that goes into the device will provide an accurate reading. 
  • Accurate readings means no problems with reports sent to your monitoring agency.

Not every interlock provider chooses to use this particular blow pattern. Most providers use either the blow-inhale-blow or the straight blow pattern. The blow-inhale-blow is more difficult to master, thus increasing the risk of annoying aborted tests.

While not specifically related to blow patterns, State requirements have some influence on how an ignition interlock is designed to get sufficient breath samples. 

Here’s what most states need:

  • 1.2 liters to 1.5 liters of breath with each and every test so an accurate breath alcohol concentration (BrAC) reading can be collected.
  • Most states also require some anti-circumvention so that device users can’t cheat and use some other source of air other than human breath.

It might be a bit geeky, but let’s talk about industry certifications? This really has more to do with overall reliability and accuracy than just blow patterns. Success in your interlock program requires an ignition interlock device that performs accurately and reliably. If a device has passed the rigors of testing required by the National Highway and Traffic Safety Administration (NHTSA), then you can rest assured it received top marks in those two categories.

LifeSafer’s Ignition Interlock devices have a blow and hum pattern and meet all of the above requirements. Each device:

  • Makes testing quick and easy
  • Captures 1.2 – 1.5 liters of breath with each test
  • Avoids circumvention by detecting ONLY human breath
  • Is NHTSA certified for reliability and accuracy
  • Delivers accurate and timely reporting

Ready to get started? Give our Customer Support Center a call at 800-634-3077. One of our experts will help get your installation booked and answer all your questions about your state-specific interlock program. You will regain your freedom to drive in no time.

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