If you have ever been pulled over by an Arizona law enforcement officer on suspicion of drinking and driving, you may have been asked to take a breath test. Law officers use these devices to measure the amount of alcohol a person has in their blood, and ensures it is not over the legal limit of 0.08. Yet it gets the BAC level indirectly. Rather than measuring your BAC level from an actual blood sample, a breath test device measures the amount of ethanol molecules in an exhaled breath sample. The problem lies in the fact that breath test devices do not always provide accurate results and are often unreliable.

According to research performed by the State University of New York at Potsdam, BAC level readings from a breath test device can vary by up to 23% from actual blood test results. Furthermore, one in every four people tested run the risk of showing inflated results, which could lead to an erroneous DUI arrest.

There are a myriad of factors that can lead to inaccurate breath test device results. The devices may pick up other elements that are similar in structure to ethanol alcohol. Other factors include the following:

  • Food, blood, vomit or drink left behind in a person’s mouth
  • Cigarette smoke, pollution and dirt in the air
  • The temperature and relative humidity of the air
  • Static interference from cell phones and officer radios
  • Gasoline and cleaning fumes

When an officer uses a device that has not been calibrated correctly or uses the machine wrong it can have an impact on the results as well. If you should get pulled over by a law enforcement officer, you should be aware of your rights and legal options.

This information is intended to educate and should not be taken as legal advice.