How is BAC Calculated?

Experienced Fort Lauderdale DUI Lawyers – (954) 840-8713

Your blood alcohol content (BAC) level is used to determine if you are legally intoxicated and can be arrested for driving under the influence of alcohol. In all states, your BAC cannot exceed 0.08. If your BAC is higher than this level, you can be arrested for a DUI. If you are arrested on suspicion of a DUI, contact our Fort Lauderdale DUI attorneys at Hager & Schwartz, P.A.

Tests used to determine your BAC are:

  • Blood tests
  • Urine tests
  • Breath tests

Breath tests are commonly used at the time of your arrest, since this test has instant results. Blood and urine tests must be analyzed in a lab, and it may take several weeks to get the results of the tests. A breath test may be administered first, and a blood or urine test may be administered later if there is doubt about the accuracy of the breath test.

What Does BAC Mean?

Your blood alcohol content, or BAC, is the amount of alcohol in your blood stream. This is easily tested because alcohol is absorbed directly into the blood stream, rather than being digested the way food would be. It takes about 50 minutes for your body to absorb alcohol into your blood stream. Once the alcohol has been absorbed, it will travel through your body to all of your cells, including your brain. Once your brain has been reached, you will experience reflex impairment and reduced neurological functioning. This impairment causes the feeling of drunkenness.

Your liver is responsible for processing alcohol out of your blood stream and eliminating it through your breath, urine, and sweat. Your metabolism sets the pace for how quickly you can expel alcohol from your body. When you continue to drink faster than your body metabolizes alcohol, your BAC will rise. On average, your BAC will rise by 0.02 for each drink you consume beyond one drink per hour.

Breath Tests

Commonly known as a Breathalyzer, a breath test samples your breath for alcohol. For an accurate reading, you will need to provide a continuous breath sample for 30 seconds. The alcohol concentrations in your breath are 2,100 milliliters to 1 milliliter of the levels of alcohol in your blood. What this relationship means is that 1 milliliter of blood has the same alcohol content as 2,100 milliliters of air. This test will usually be conducted at the time of the stop.

Blood Tests

These tests are less relied upon because they require a lab to analyze the results. Because the driver must be taken to a hospital or other facility for the test, it can be difficult to ensure that the test is performed shortly after the stop. If the test isn’t performed quickly, the reading may be inaccurate to the BAC level that the driver had while driving. This is due to the body continuing to process alcohol into the blood stream.

There are three types of blood tests that can be performed: serum, whole blood, and plasma. Whole blood is made of cellular material, plasma, and fibrinogen, which is a clotting agent in blood. This blood test tests a sample of blood that hasn’t been separated. Serum tests test your plasma, once the fibrinogen has been removed. Plasma tests test plasma that has been separated from the cellular material in your blood.

The type of blood test you receive is important to know, since serum and plasma tests can result in a BAC that is 16% higher than a whole blood test would produce. This is because there is the same amount of alcohol, but there is a smaller volume of liquid. The alcohol will constitute a much larger portion of the total sample. If you are being tested, ask the lab tech what kind of test is being performed. This information can be crucial for your defense attorney to build your case.

Start Your Defense with Fort Lauderdale DUI Lawyers – (954) 840-8713

After a DUI arrest, you have a limited amount of time to protect your driving privileges and build your defense. Our Fort Lauderdale DUI attorneys can get started on your case immediately, and can help you with every aspect of your DUI case. Don’t face your DUI charges alone. At Hager & Schwartz, P.A., we are available 24/7 to take your call.

Call today! Contact Hager & Schwartz, P.A. at (954) 840-8713

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