Are Portable Breath Tests Reliable?

October 31, 2018

Category: ,

I get a lot of questions about the portable breath tests. Police officers use these devices at roadside to see if a driver is “over the limit”. But are these devices even accurate?

These inexpensive devices are notoriously inaccurate and can over report your BAC greatly. There are a few reasons for this.

Issue #1: Residual Mouth Alcohol

One of the issues with the portable breath tests (PBTs) is that it is susceptible to over reporting due to “residual mouth alcohol”. This is the alcohol that is still in the mouth after a drink. The device will see that as a high concentration of alcohol and over report the BAC, even though that level of alcohol is not present in the blood. This is a big issue that is common with these devices.

Issue #2: They Detect other Forms of Alcohol

PBTs can’t tell the difference between ethanol and other chemicals that have similar properties. This is why if you were using a paint thinner, hand sanitizer, nail polish remover, mouthwash and many other substances, the PBTs can over report your BAC.

Issue #3: They are not Specific to Alcohol

Many common substances, which have no similarity to ethanol, can also cause an inflated BAC reading. There have been tests done that show even simple foods like white bread can cause a reading on these devices.

If you have recently been pulled over for OUI or DWI and believe the PBT showed an inflated reading, please call us now at (888) 526-9737. At Bowser law, we will examine your case and formulate a strategy to protect your rights. People who can’t afford a DUI trust Mike Bowser.

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Mike Bowser has unique experience and knowledge which he uses to protect his clients.

  • Mike Bowser is the only Board Certified DUI Defense Specialist who practices in MA, NH & ME. This means he had to pass rigorous examinations and interviews about his knowledge of DUI law to become certified.
  • Because he practices in all three states, Mike Bowser knows how to handle the complications that arise when you are charged as an out of state driver.
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