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What Is BAC? (Blood Alcohol Content)

By: William C. Head, DUI Lawyer Atlanta GA

The amount of alcohol in your bloodstream is called BAC. Blood Alcohol Content (BAC) is a medical and technical term for the measure of how intoxicated a person is. This is often measured through alcohol breath tests, blood tests, and alcohol urine tests. Learning how to estimate the amount of alcohol in your bloodstream can be extremely useful. This can help someone know when it is unsafe to get behind the wheel. If everyone estimated their Blood Alcohol Content, then there would be much fewer drunk drivers on the road.

Thousands of Americans go to the internet daily seeking to find an alcohol level DUI calculator. If I want to calculate my BAC, multiple factors about the drinker must be known to calculate your blood alcohol level. Most people will not be carrying an alcohol blood level calculator or a BAC calculator chart. Some smartphone users have likely downloaded a blood alcohol content calculator “app”, but these are usually not used once a person has started drinking alcohol.

What’s My BAC?

To answer the daily question, “What is my BAC?”, you will need to know many basic factors to plug into a BAC level calculator, including:

Gender and BAC

Men tend to process alcohol better than women based on BAC by weight since women are genetically predisposed to carrying more body fat. This is because childbearing favors this type of body.

By way of example, a man of 170 pounds versus a woman at 170 pounds may have drastically different body types. Assume the woman is 5’1” tall, and the man is 6’1” tall. Since only “lean body tissue” (muscle) processes alcohol out of the body, an overweight woman should calculate her lean body weight at 100 pounds. The man is already at normal-to-low lean body weight.

Using ballpark estimates to calculate alcohol level, he can drink about 2 of the same type, quantity, and proof level drinks to calculate blood alcohol.

Muscle Density and BAC

Don’t simply look for BAC by weight, in light of only muscle tissue processing alcohol. A 115-pound MMA fighter, male or female generally has near zero body fat, and these athletes may be 5’7” tall. They can skew any standard BAC chart for male drinkers or BAC chart for female drinkers, in light of this abnormally “fit” body composition.

Beverage Alcohol Percentage and BAC

Knowing the alcohol content of your beverage is critical since booze comes in all sizes, shapes, and mixtures in pre-packaged or bar-poured containers. Three quick examples of the wide variation in drink delivery – both in ounces of alcoholic beverage and in proof level make a huge difference.

In the blood alcohol calculator business, whether an online system or a pre-printed “calculate my BAC” chart, EVERY alcohol level calculator utilizes “a standard drink” equation.

A standard BAC calculator chart looks like this:

BAC Calculator
So, a “standard drink” means that the above types of alcoholic beverages have roughly the same amount of pure ethanol (alcohol) in each. Many people may dilute a liquor drink with Coca-Cola or Sprite, and some wine drinkers may dilute wine with sparkling water or ginger ale.

Time is the most vital blood alcohol calculator factor

This rule is fairly simple. The human body, on average, can only ELIMINATE (burn-off) a 0.015-gram percent of ethanol. So by waiting 1 hour, you only burn off a fraction of a drink. First, look at a BAC chart and then deduct for time. So long as no more ethanol is added, the person drinking any of the 3 described alcohol drinks will be ingesting approximately the identical amount of “poison” (alcohol) into his or her body.

A substantial number of web surfers are seeking BAC calculator information to be able to learn how to beat a breathalyzer test. Some are researching an existing DUI charge, and don’t believe the reported breath alcohol test is accurate. The value of this simple chart is to first be realistic about your lean body weight. Then, look at the number of standard drinks. You can’t let a fancy restaurant that charges $12 per glass and pours you DOUBLES overestimate “1 standard drink” that is between 8 oz and 10 oz each drink, so count each glass as two drinks.

Finally, any blood alcohol calculator over time must allow for sufficient time to metabolize enough alcohol to calculate alcohol content before driving. If an error is made, err on the side of not being over the limit for driving under the influence.

How does my tolerance affect a blood test for alcohol?

Drunk driving lawyers have heard many clients argue that they were not drunk, but the officer still arrested them. Police are keenly interested in getting the blood alcohol test from you because they know that tolerance does not matter in a DUI per se drunk driving case. Instead of focusing on “what blood alcohol level is drunk,” look at the BAC blood readings or the breath alcohol test numbers. THIS is what your prosecutor will use to try to convict you in court.

Will I pass a drunk driving test? How to beat a DUI?

Drunk driving defense is a complex and difficult practice area for attorneys. In the past 70 years, the “acceptable” sobriety test number for adult motorists went from 0.15 in 1946, to 0.10 in the 1960s, to 0.08 for all States by 2005. Today, anti-DUI opponents are pushing for a new legal limit of 0.05 in America. This is the standard used in most of Europe.

So, if this is how DUI per se cases will be judged soon, being familiar with all of the above human factors, in utilizing any drunk calculator, may save your right to drive. Look at a reliable and accurate alcohol BAC calculator, and be conservative in calculating your blood alcohol level over time. That is how you beat a breathalyzer test if you are pulled over after consuming alcoholic beverages. And that is how to beat a DUI!

Criminal Defense Attorney Explains BAC Test Results

Driving under the influence is the number one most litigated criminal law trial in America. For over 20 years, more than 1.5 million drunk driving arrests (on average) were made in the United States. Therefore, a DUI sobriety test exists in most of these driving while intoxicated cases.

How do I calculate BAC?The amount of alcohol in your blood is called your Blood Alcohol Content. This can be calculated or estimated to see if you are sober enough to drive. Most accused citizens with a criminal case that has DUI blood test results (or breath test results) never ask their DWI defense attorney how to measure blood alcohol level, or how do you calculate BAC?

Although most DWI-DUI-OWI cases involve a breathalyzer test, many of the more serious criminal law prosecutions have blood tests for the DUI sobriety test. Several reasons exist for the use of a blood alcohol test.

The 5 most common fact patterns for having a blood test in an impaired driving criminal case are:

Independent Testing

In states like California that allow a DWI/DUI suspect to opt for a voluntary blood test and not take the breath alcohol test mandated by the implied consent law, an arrested drunk driver may elect a blood level analysis over a breathalyzer test so that independent testing can be obtained. Several states, like South Carolina and California, have DUI laws that default to a breath test when only DUI alcohol is suspected.

DUI Drugs

Where drugs are the only impairing substance suspected (no smell of alcohol or admission of consuming alcohol), a breathalyzer cannot detect or quantify any drugs, except ethanol (alcohol). Thus, a blood test or urine test would be the police officer’s choice of sobriety test for people charged with drugged driving.

After the case of Missouri vs. McNeely in 2013, many arresting officers are seeking a search warrant from a judge before drawing blood for a DUI sobriety test for drugs. Your criminal defense attorney may challenge the legitimacy of the DUI blood test results.

DUI Breath Test Refusal

Where a DUI sobriety test of breath is sought by an arresting officer, and this type of implied consent test is refused by the drunk driving suspect, most states have statutory provisions to enable the arresting officer to seek an electronic warrant or a regular, in-person warrant from a magistrate judge or other judge. Upon a proper showing (such as an affidavit of the facts supporting the drunken driving arrest) will authorize the issuance of a blood test for alcohol, drugs, or both.

Driver Incapacitation

In accident cases, where the DWI suspect is unconscious or otherwise incapable of answering the implied consent questions of whether they will agree to a blood sobriety test, almost all states have passed drunk driving laws that allow “consent” to be given, when the suspected intoxicated driver is incapable of consenting. So consent is “implied” under the provisions of informed consent or implied consent law in the state.

Crashes With Fatalities

In serious vehicle crashes involving the death of one or more people in a drunk driving wreck (with other vehicles or with a pedestrian, or a serious boding injury to another person), the existence of reasonable suspicion of one or more drivers being impaired can be the basis of a law enforcement officer utilizing a statutory provision or (more likely) a judicial search warrant to forcibly draw blood and/or collect urine, to determine the BAC level or the drug concentration within a DUI driver’s bloodstream.

Fighting BAC Results

With any felony DUI or other situation that involves a blood test, for alcohol or drugs, you need to have a DUI defense attorney at your side. If you cannot afford to hire a private criminal defense lawyer, you should seek to qualify for an appointed criminal attorney who is skilled in impaired driving cases, and the scientific evidence associated with drunken driving cases or drugged driving cases. Your criminal lawyer must know how to calculate blood alcohol levels as done by the state crime laboratory.

Furthermore, your impaired driving lawyer must know all of the rules about DUI drugs cases or DUI felony charges involving prescription drugs, relating to a therapeutic dose of any lawfully prescribed medications. This type of driving while impaired case typically involves the DUI defense attorney locating an expert witness in pharmacology and the pharmacokinetics of drugs.

If you need an appointed lawyer, see your court administrator to apply for a public defender. If you need a private criminal defense lawyer, call 1-888-839-4384 to be connected to a private criminal attorney who can review your case and assist you in your criminal law case.

Further Reading

If you’d like to learn more about blood alcohol content and how BAC can be used against you, read some of our helpful and informative articles on BAC below:

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