Mechanics Behind the Breathalyzer

You may have seen a breathalyzer before, whether on screen or in person, but do you know how it works? While it may seem simple, the mechanics behind breathalyzers are fairly complex.

How does a breathalyzer work?

Houston Criminal and DWI Defense Attorney

Alcohol contains ethanol, which absorbs into a person’s bloodstream while drinking beer, wine, and liquor. When you inhale, some of the ethanol in your blood vaporizes into your lungs and is then exhaled. Higher concentrations of ethanol upon exhaling indicate higher levels of alcohol in the bloodstream, thus providing a measure of intoxication.

When you blow into a Breathalyzer, the ethanol is captured and measured. You must blow into the Breathalyzer for three seconds to get an accurate reading.

Types of Breathalyzers

You may not have realized it, but there are actually three different kinds of breathalyzers. A semiconducter oxide-based breathalyzer is a low-cost option that is easy to get, but is also more prone to false readings.

A fuel cell breathalyzer is a more professional-level tester that uses chemicals to oxidize the alcohol in the breath sample to create an electric current. The more current produced, the more alcohol in the sample.

Spectrophotometer breathalyzers are the kind you’ll find at police stations. They use a more complex process of infrared detection, which analyzes how the different molecules in the breath sample absorb infrared light. As a result, they are more accurate and less likely to produce false positives.

If you are looking for DWI-related representation, contact Houston criminal defense attorney Jim Medley today!

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Jim Medley

For more than 20 years, attorney Jim Medley has perfected his craft in the field of criminal justice. He garnered extensive knowledge during his 12 years as a police officer in Texas, and applied that knowledge during his time as a professor of criminal law and criminal justice. Mr. Medley brings a unique skill set to the table, and as a result, he would be an invaluable asset in the courtroom should you need DWI or criminal defense in Houston.

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