Calculating Blood Alcohol Concentration (BAC)

Blood Alcohol Concentration (BAC) measures the amount of alcohol present in your bloodstream. Knowing how to calculate your BAC can be vital in many situations, whether you’re heading home after a night out or if you’ve been stopped for Driving Under the Influence (DUI). If police stop you for a suspected DUI, they may ask you to perform field sobriety tests. These often include tasks like standing on one leg, tracking a light with your eyes, or walking in a straight line, heel-to-toe. If you fail these assessments, the officer may suspect impairment from drugs or alcohol and request further testing, such as a breathalyzer or a chemical test of your blood or urine.

What Exactly Is Blood Alcohol Concentration?

When you drink alcoholic beverages, the alcohol enters your bloodstream, causing your blood alcohol concentration to rise. In most states, including Pennsylvania, the legal limit for adults is 0.08 percent. If your BAC exceeds this limit, you could face DUI charges. A BAC test specifically measures the alcohol in your system, with a result of 0.08 meaning there are 0.08 grams of alcohol for every 100 milliliters of blood.

For those under the legal drinking age, Pennsylvania enforces a zero-tolerance policy. This means that a BAC of just 0.02 percent or higher results in an automatic DUI charge for underage drivers. If you are facing such charges, it is crucial to consult a Harrisburg DUI attorney to understand your rights.

What Factors Influence Your BAC?

Several variables can impact how alcohol affects your body:

• Gender: Women typically have a higher BAC than men after consuming the same amount of alcohol. This is generally because women often have a smaller physical build than men.
• Body Fat Percentage: A higher percentage of body fat can lead to a higher BAC. Body fat does not absorb alcohol as efficiently as other types of tissue.
• Empty Stomach: Drinking without eating first can cause your BAC to rise more quickly than if you had a meal with your drinks. Food in the stomach slows down the absorption of alcohol, leading to a lower BAC.
• Body Size: Smaller, lighter individuals generally have a higher BAC than larger, heavier people because there is less space for the alcohol to distribute throughout the body.

If you believe these factors may have affected your test results, a Harrisburg federal criminal lawyer can help examine the details of your case.

How to Determine Your BAC

To estimate your BAC, you first need to know the standard alcohol content in various drinks. One standard drink is defined as a 5-ounce glass of wine, a 1.5-ounce shot of liquor, or a 12-ounce beer. Wine usually contains about 15 to 20 percent alcohol, liquor ranges from 30 to 50 percent, and beer is typically around 4 to 4.5 percent. Mixed drinks can be deceptive; for instance, a Long Island Iced Tea contains five different spirits and has an alcohol content of approximately 22 percent.

To calculate your BAC, you need four key pieces of information: how long you have been drinking, the ounces of alcohol consumed, the alcohol percentage of those drinks, and your weight. Widmark’s Formula is a common tool used for this calculation:

BAC = (ounces of alcohol consumed x 5.14 / weight in pounds x gender constant) – 0.015 x hours since drinking started.

The gender constant used for alcohol distribution is 0.66 for women and 0.73 for men.

Let’s look at an example: Imagine a 150-pound woman has engaged a Harrisburg DUI attorney after being stopped. She explains she drank two 12-ounce beers over the last two hours.

• % BAC = (1.20 x 5.14 / 150 x 0.66) – 0.015 x 2
• % BAC = (6.168 / 99) – 0.03
• % BAC = 0.062 – 0.03
• % BAC = 0.032

In this scenario, her BAC is 0.032, which is below the legal limit of 0.08 percent for adults, meaning she is not legally intoxicated.

What to Do If Your BAC Is Too High

It is critical to remember that you must comply with the legal requirement to submit to a BAC test. Refusing a blood or breath test in Pennsylvania results in an automatic license suspension and an additional criminal charge. If you are arrested for DUI in Dauphin County, seek immediate help from a skilled professional.

If you are facing charges for Driving Under the Influence, you need the expertise of a knowledgeable Harrisburg federal criminal lawyer. At Logue Law Group, we have successfully managed numerous DUI cases throughout the region. Our services cover Harrisburg, West Virginia, and Ohio. Contact us today for an initial consultation at 412-387-6901 or visit our website to get in touch with a dedicated Harrisburg DUI attorney.