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Are Breathalyzers Accurate

Breathalyzer Accuracy


Call Houston DWI Lawyer Clyde W. Burleson at ☎ 713-628-1503 For a Free Consultation

Are Breathalyzers Accurate?

In short, the answer is no. Moreover, that fact can be a big advantage if you’re arrested for DWI in Houston. Breathalyzer is actually a brand name that has become synonymous with the technology similar to Xerox, but other brands include BAC Datamaster, Alcoscan, Alcosensor and Intoxilyzer.

Most breathalyzers report test results by a measurement of 210 ltr while the average breathalyzer tests an average of 80cc of breath. It only takes approximately one millionth of an ounce of alcohol in that small a size breath sample to get a .10, which is a significantly illegal reading based on a extremely small sample size. This type of science would not be taken seriously in any other field.

Breathalyzers Don’t Test BAC

The biggest issue with these machines is that they don’t test blood alcohol concentration (BAC), they estimate BAC indirectly by measuring the the amount of alcohol in one’s breath. Additionally, breathalyzer’s don’t only identify ethanol (beverage alcohol) but also identify any compound containing the methyl group structure. Here’s a list of compounds that can be incorrectly identified as ethyl alcohol:

  • Acetone – Common in levels 100X in diabetics and dieters (such as the keto diet)
  • Medications such as asthma medications, over-the-counter cold medication and oral gels
  • Mouthwash & breath sprays (Binaca)
  • GERD & Acid Reflux
  • Lacquers
  • Paint Removers
  • Celluloid
  • Gasoline
  • Cleaning fluids
  • Blood or vomit

Breathalyzers & Outside Factors

Other outside factors that may lead to a false positive DWI include:

  • Electrical interference from cell phones & police radio
  • Tobacco smoke
  • Dirt
  • Moisture
  • High body temperature
  • High air temperature

Breathalyzers & Human Error

In addition to asking “are breathalyzers accurate”, you must also ask “is there room for user error.” Human error may alter breathalyzer samples more so than the limited technology. Although officers are trained in the proper use, maintenance, and reading of breathalyzer tests, there is a lot of room for error. Human error can often show up in the form of:

  • Failure to use the breathalyzer properly
  • Improper maintained breathalyzer
  • Failure to re-calibrated breathalyzer as needed

With so many variables that cause false positives, there’s a lot of room for argument when it comes to your DWI defense.

Call Houston DWI Lawyer Clyde Burleson

In conclusion, you need a proven DWI lawyer to make sure your breath test was accurate. Above all, call Houston DWI Attorney Clyde W. Burleson today at 713-628-1503 for a free consultation.

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