Are breath test readings accurate?

Are breath test readings accurate?

On Behalf of | Sep 13, 2021 | blog

Getting pulled over by law enforcement on suspicion of drunk driving is often nerve-wracking. During this intimidating situation, an officer may ask you to complete a roadside breath test. Officers in Florida and throughout the United States use these devices to determine whether drivers have a blood alcohol content level over the legal limit of 0.08.

Yet, studies show that the results from roadside breath tests are not always accurate. In fact, unreliable breath test results can lead to a wrongful DUI arrest and potential charges. According to the State University of New York at Potsdam, one in four people who are given a test will show inflated breath test readings.

How do breath test devices work?

When you exhale into the device, it detects the amount of ethanol alcohol in your breath sample. The machine, however, can also pick up substances that have a similar methyl structure, and this can influence the final reading.

Researchers from the State University of New York at Potsdam found that when breath test readings were compared to the results from an actual blood test, they differed by at least 15%. This variation may lead to a wrongful DUI charge.

What factors affect breath test readings?

Studies show that certain factors lead to a fluctuation in breath test results. These factors include the following:

  • Residual drink, vomit, blood or food in the mouth
  • Electrical interference from officer radios and cellphones
  • Temperature and relative humidity of the air
  • Inhaling fumes from gasoline, cleaners, paint or paint thinners
  • Using the machine incorrectly

Breath test devices must be calibrated regularly as well.

It is important to know that there is the potential for your breath test to show inflated results and the readings given on the machine may not accurately represent your current blood alcohol content level.