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Breath Testing

If you are ever pulled over by an officer who suspects you are under the influence of alcohol, you may be asked to perform a breathalyzer in order to determine your blood alcohol content (BAC). Depending on the results of this test, you could also be arrested and charged with driving under the influence, a crime known as DUI. But how exactly does breath testing determine whether a person is under the influence of alcohol? Here's what you need to know about how breathalyzers work.

In the United States, it is illegal for anyone to operate a vehicle with a BAC of 0.08% or higher, as studies indicate this amount of alcohol can substantially reduce a person's ability to drive safely. As a result, breathalyzers are designed to calculate a suspected DUI offender’s BAC and help officers identify drunk drivers.

Breath testing devices work by estimating a person's BAC based on the amount of alcohol found in his or her breath. In order to do this, the person must blow into a small tube located on the breathalyzer. If the device detects the presence of alcohol, it uses a set ratio to calculate the test subject’s BAC. Unfortunately, this means that the calculation is not always correct, as there are a number of variables that can affect a person's BAC reading.

For example, breathalyzers assume the amount of alcohol found in a person's mouth is representative of the amount of alcohol in his or her bloodstream. This means that the test can easily pick up traces of alcohol from other substances, such as breath mints, cough syrup, chewing gum, or other products that contains a small amount of alcohol. In such cases, the BAC will be falsely inflated due to the presence of mouth alcohol.

In addition to the substances listed above, there are numerous medical conditions that can also affect a person’s breath test results—such as acid reflux disease, diabetes, and respiratory disorders, just to name a few. In fact, breath tests have been known to pick up fumes from paint, adhesives, and other chemicals. It’s also not uncommon for the device to mistake acetone for alcohol, which means individuals on low-carb diets can also receive an inflated BAC reading (since the body often produces acetone in response to their eating habits).

With such inaccuracies, you can certainly see why breath testing is far from an exact science. Each year, thousands of drivers are falsely arrested due to the results of this flawed device. For this reason, any driver who fails a breathalyzer should discuss his or her results with an experienced DUI attorney immediately.

If you were recently arrested for DUI after a breath test indicated you were driving with an illegal amount of alcohol in your system, don’t simply assume the results are valid. In many cases, you may be able to prove your BAC was elevated due to mouth alcohol and in turn, avoid the devastating consequences of a drunk driving conviction.

To learn more about how you may be able to challenge your breath test results, contact an experienced DUI defense attorney in your area today.

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