Are Breathalyzer tests always accurate?
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Are Breathalyzer tests always accurate?

On Behalf of | Feb 10, 2021 | DWI

An estimated 50% of motorists who cause car crashes have a blood alcohol concentration (BAC) of 0.16% or more, a percentage that’s double Texas’ legal limit of 0.08%. Many police officers perform field sobriety testing after pulling over a suspected drunk driver. They tend to have suspects undergo Breathalyzer testing after making an arrest — and prosecutors often base the charges they file against a defendant, in part, on their BAC.

The disturbing part of all this is that Breathalyzer tests aren’t always accurate

How do Breathalyzers work?

These machines function by picking up on methyl molecules and ethanol that compose 80% of human breath and alcohol. Breathalyzer units often mistake these two compounds for ethyl alcohol. When this happens, it can cause someone to fail their test even though they may not be intoxicated. 

The food that a person consumes before submitting to a Breathalyzer test can even change their results. Bread, for example, is one food item that can unexpectedly cause your BAC level to soar temporarily. Some personal hygiene products, such as mouthwash, and over-the-counter medications like cough syrup may have the same effect. 

Individuals with certain medical conditions, such as diabetes, may have a high acetone level in their bloodstream and thus fail a Breathalyzer test as a result. Those exposed to particular environments, such as 20 minutes in a spray-painted room, may see an increase in their methyl molecule percentage in their bloodstream and have an abnormally high BAC as a result. Even the ambient temperature can impact the accuracy of Breathalyzer results.

Don’t let an erroneous Breathalyzer test convict you

No one should be wrongly convicted of drunk driving. If you’ve been charged with a DWI, an experienced Dallas defense attorney can advocate for you.