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What you need to know about tests for blood alcohol content

On Behalf of | Aug 28, 2019 | Uncategorized |

A charge of driving under the influence of alcohol is a serious one. Though many people who choose to drive after drinking might think that they are capable of operating a vehicle, the law states that those whose blood alcohol content, or BAC, is above a certain level may not drive legally. It’s the kind of arrest that officers make all too frequently.

If authorities charged you with a DUI here in Georgia, you may have several questions regarding your BAC. Understanding exactly how law enforcement acquires and uses this information may help you in defending yourself against these charges. Here is what you need to know about the measurement of your BAC.

Ways to determine BAC

Law enforcement determines BAC from samples taken from various places on a person’s body. Testing of your urine, saliva, hair, blood or breath determines if you are over the legal limit. The most common testing involves a blood or breath sample.

You may have heard of Breathalyzer tests, which analyze the amount of alcohol in a person’s breath. Older machines used a wet chemical process to reference a suspect’s breath in comparison to a sample. Newer Breathalyzers use infrared spectroscopic analysis to measure how much alcohol is in a person’s exhalation. According to scientific research, depending on how much alcohol vapor is present in a suspect’s breath, the alcohol vapor absorbs a certain frequency of light wave.

The accuracy of a Breathalyzer

Though you may have heard otherwise, Breathalyzers provide an accurate method of determining whether a person’s BAC is over the legal limit. Blood tests are more accurate, but they are also more invasive, meaning people aren’t as likely to willingly submit to having one conducted. Some studies report that there can be up to a 15% difference in the measurement of BAC between a breath or blood sample. There are some cases where courts threw out the results of a Breathalyzer because of questions over the accuracy.

Common misconception about Breathalyzers

This uncertainty may cause some to believe in certain myths surrounding Breathalyzers. Some people think that they can beat a Breathalyzer by using breath mints or mouthwash. Others say eating onions or pennies can falsify results, but none of this is true. However, people may challenge the results of a Breathalyzer in court, though many people don’t realize that. A Breathalyzer is a machine, and just like any machine, it can malfunction. It needs regular testing and calibration, though that doesn’t always happen.

Some people advocate purchasing personal BAC-testing devices. While some of them work, many do not, and it is difficult to determine which ones will be helpful. Some say that the best home test is alcohol test strips used with one’s saliva. The amount of alcohol in a person’s saliva is usually similar to that of the bloodstream. However, these personal testing kits cannot be used as evidence in court.

If you got a DUI

If you face charges for DUI, you should keep in mind that it can significantly affect your future employment prospects or raise your insurance rates, not to mention the potential jail sentence or extensive fines you could face upon conviction. Because of what all is at stake, it is imperative that you understand your options to defend yourself against these charges, and consulting with an experienced criminal defense attorney is a good place to start.


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