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Challenging breath test measurements

On Behalf of | Dec 27, 2019 | drunk driving defense |

You might think that having a breath test measurement indicating that you were intoxicated is irrefutable proof of you having driven under the influence of alcohol. Such is the assumption held by many of those in Shalimar who come to see us here at the Campbell & Madden, PLLC Yet there may be inherent flaws with breath measurement devices that make their results less than reliable as proof of intoxication. Indeed, the American Motorists Association has shared research which suggests that they may have a margin of error as high as 50 percent! 

How is that breath testing devices are able to make an estimation of the alcohol content of your blood? The answer to that question requires understanding how alcohol gets on your breath. The alcohol you ingest dissolves into your blood and eventually makes its way to your lungs, where a portion of it vaporizes upon coming in to contact with the oxygen that you breathe in. This gaseous alcohol is then expelled as you breathe. The process of vaporization continues, maintaining an equilibrium between the amount of alcohol that you breathe out with the concentration still in your blood. 

Per the Alcohol Pharmacology Education Partnership, that equilibrium is assumed to be 2100:1 (one part of alcohol on your breath for every 2100 still in your blood). However, your equilibrium level can actually range from 1500:1 to 3000:1, depending on factors such as: 

  • Your age, gender, and genetic makeup 
  • Your actual state of intoxication 
  • The time the test is taken 
  • The actual measurement device used 

This information may provide the basis for challenging a BAC measurement being used against you. 

You can learn more about answering to DUI charges by continuing to explore our site.