Blood Alcohol Content

blood alcohol content

What is Blood Alcohol Content?

Your blood alcohol content (BAC) (also known as blood alcohol concentration level) measures the amount of alcohol in your blood, therefore traveling through your body to every organ, including your brain. In its simplest form, calculating a person’s BAC level is based on how much alcohol went into what kind of body over a period of how much time.

The blood alcohol content is commonly expressed as a percentage of alcohol per volume of blood. For example, in the United States (US), a BAC of 0.08 (0.08%) would translate to 0.08 grams of alcohol per 100 mL of blood.

In the US, the legal limit for BAC when driving is 0.08%. Drivers who are over the age of 21 (the legal drinking age in the US), who have a BAC equal to or greater than 0.08%, can face penalties. Penalties for those under 21 are stricter but vary by state. For those under 21, the legal limit ranges from 0.01% to 0.05%.

blood alcohol content
According to CDC [1], almost one in three traffic deaths in the United States involves a driver with a blood alcohol content (BAC) of 0.08% or higher. Alcohol-impaired driving laws make it illegal to drive with a BAC at or above a specified level (0.05% or 0.08%, depending on the state).

How is Blood Alcohol Content Measured?

Your blood alcohol content (BAC) is determined primarily by how much alcohol you drank, your weight and your gender, the rate of consumption. Other factors include hydration level, other drugs in the system, food in the stomach, type of drink.

0.01 to 0.07 blood alcohol content (BAC)

You feel a little lightheaded or mildly relaxed. You feel less cautious and your inhibitions are loosened. Judgment abilities are slightly impaired. No natural feeling of depressant effects of alcohol has been seen yet. Your behavior may become exaggerated, and your emotions intensify.

0.08 to 0-.13 blood alcohol content (BAC)

Your motor skills become impaired, and your sense of balance may be compromised. Your emotions become a bit exaggerated – perhaps aggressive, perhaps loud. It is illegal and dangerous for you to drive. Your judgment is impaired, and you may have a problem evaluating sexual situations. You think you are functioning better than you actually are.

0.14 to 0.19 blood alcohol content (BAC)

The “good feelings” of euphoria start to give way to negative feelings such as restlessness and anxiety. You may start feeling tired because the depressant qualities of alcohol take effect. (If you are a male adult, you will have a problem achieving or maintaining an erection.) You will have trouble walking or standing and are at a greater risk of hurting yourself physically. You may get nauseous.

0.20 to 0.24 blood alcohol content (BAC)

You feel confused and disoriented. At this stage, you may experience nausea. You may also have trouble standing. You may not realize that you injure yourself because you might not feel pain. Alcohol blackouts are possible at this point.

0.25 – 0.29 blood alcohol content (BAC)

Almost all aspects of your brain are severely impaired. You may have passed out by this point. Vomiting is likely and the chance of asphyxiation on your own vomit is greatly increased. If you haven’t passed out, the risk of personal injury is high because you have little to no physical control. You are emotionally numbed.

0.30 to 0.34 blood alcohol content (BAC)

If you are still conscious, you are in a stupor. You likely have no awareness of what you are doing or where you are. There have been multiple alcohol poisoning and death cases in this range of blood alcohol content BAC. You require medical help.

0.35 & up

You have reached the level of surgical anesthesia. Coma is possible. The lungs and heart rate are slowing to the stage of stopping. You need immediate medical help.

Blood Alcohol Content Depends On

Many factors can affect your BAC measurement, including the following:

  • Amount. The amount of alcohol is the most obvious factor and the most important.
  • How quickly you consume. Four drinks within one hour, for instance, will produce a higher blood alcohol content than four drinks within three hours.
  • Body mass. Individuals with higher body weights are not affected by alcohol as quickly as people with lower body weights.
Blood Alcohol Content
Alcohol use slows reaction time and impairs judgment and coordination, which are all skills needed to drive a car safely. The more alcohol consumed, the greater the impairment.
  • Food in your stomach. The food in your stomach will absorb some of the alcohol, reducing the rate at which it is absorbed into the bloodstream. Alcohol drunk on an empty stomach will be absorbed by the body more quickly, resulting in an increased blood alcohol level.
  • Type of mixer used for mixed drinks. Alcohol is not absorbed as quickly when water and juices (non-carbonated beverages) are used to make mixed drinks. However, when carbonated beverages such as soda or energy drinks are used, the alcohol absorption rate can be quicker. Quicker absorption rates will usually lead to increased blood alcohol content.
  • Gender. Women tend to reach higher blood alcohol content levels more quickly than men. If a man and a woman consume the same amount of alcohol over a given period of time (and all other factors are held equal), the man will have a lower Blood Alcohol Level than the woman. This is because women tend to have less water and more fatty tissue in their bodies[2].

Blood Alcohol Content Levels

A person’s liver can process about one standard drink an hour. According to the Centers for Disease Control and Prevention (CDC) [2], a standard drink contains 0.6 ounces of pure alcohol.

Blood Alcohol Content (BAC) levels in standard drinks include:

  • 12 ounces of beer, or one bottle at 5% alcohol.
  • 8 ounces of malt liquor at 7% alcohol.
  • 5 ounces of wine at 12% alcohol.
  • 1.5 ounces of hard liquor, or one shot, at 40% alcohol.

The most commonly used formula to calculate Blood Alcohol Content is:

%BAC = (A x 5.14/W x r) – .015 x H, where

  • “A” is the number of liquid ounces of alcohol consumed. For example, the standard 5% beer would be .60 (12 x 0.05)
  • “W” is the person’s weight in pounds
  • “r” is the distribution ratio (.66 for women, and .73 for men)
  • “H” is the number of hours in which the alcohol was consumed

This formula is not 100% accurate when used to calculate Blood Alcohol Content. Several complex factors must be taken into consideration to accurately calculate Blood Alcohol Content, such as physical and emotional health, as well as the consumption of food.

The blood alcohol content is the amount of alcohol present in 100 milliliters (ml) or its equivalent of 1 deciliter (dL) of blood. For example:

  • 80 mg is 0.08 grams
  • 0.08 grams of alcohol in 100 ml is 0.08%
  • This can also be expressed as 80 mg/dL or a BAC of 0.08

A blood-alcohol content of 0.1 (0.1% or one-tenth of 1%) means that there are 0.10 grams of alcohol for every deciliter of blood in the person’s body at the time of the test. Synonyms for blood alcohol content (BAC) include blood alcohol level, blood alcohol concentration, and blood ethanol concentration.

In most states, the BAC level applied to drivers of commercial vehicles (including rented vehicles, such as U-Hall trucks) is lowered to 0.04%. Most states also have zero-tolerance laws regarding operating motor vehicles under the influence of alcohol for individuals who are under the legal drinking age of 21. This standard is also applied in almost every state except for special circumstances. In addition to adopting the legal limit of 0.08%, many states now impose harsher penalties on individuals who have BACs that are exceptionally high.

The courts often have less leeway regarding potential increased penalties and fines for individuals with increased BAC levels in these states and must impose harsher standards when individuals test at these levels [3]. Based on the latest available information from each state’s website, the states that have increased penalties associated with BAC level listed are listed below; states that have more than one level listed have additional penalties for each BAC level:

  • Alabama: 0.15%
  • Alaska: 0.15% (harsher penalties can be enforced at the judge’s discretion)
  • Arizona: 0.15%
  • Arkansas: 0.15%
  • California: 0.15%
  • Colorado: 0.15%
  • Connecticut: 0.16%
  • Delaware: 0.16%
  • Washington, DC: 0.2% and 0.25%
  • Florida: 0.20%
  • Georgia: 0.15%
  • Hawaii: 15%
  • Idaho: 0.2 %
  • Illinois: 0.16%
  • Indiana: 0.15%
  • Kansas: 0.15%
  • Kentucky: 0.18%
  • Louisiana: 0.15% and 0.2%
  • Maine: 0.15%
  • Massachusetts: 0.2% (for ages 17–21)
  • Michigan: 0.17%
  • Minnesota: 0.16%
  • Missouri: 0.15%
  • Montana: 0.16%
  • Nebraska: .15%
  • Nevada: 0.18%
  • New Hampshire: 0.16%
  • New Jersey: 0.10%
  • New Mexico: 0.16%
  • New York: 0.18%
  • North Carolina: 0.15%
  • North Dakota: 0.18%
  • Ohio: 0.17%
  • Oklahoma: 0.15%
  • Oregon: 0.15%
  • Pennsylvania: 0.1%
  • Rhode Island: 0.1% and 0.15%
  • South Dakota: 0.17%
  • Indiana: 0.2%
  • Texas: 0.15%
  • Vermont: 0.16%
  • Virginia: 0.15% and 0.2%
  • Washington: 0.15%
  • West Virginia: 0.15%
  • Wisconsin: 0.17%, 0.2%, and 0.25%
  • Wyoming: 0.15%

Effects by Blood Alcohol Content

Information in this table shows the BAC level at which the effect usually is first observed, and has been gathered from a variety of sources, including the National Highway Traffic Safety Administration, the National Institute on Alcohol Abuse and Alcoholism, the American Medical Association, the National Commission Against Drunk Driving.

BAC

Typical Effects

Predictable Effects on Driving

0.02%

  • Some loss of judgment
  • Relaxation
  • Slight body warmth
  • Altered mood
  • Decline in visual functions (rapid tracking of a moving target)
  • Decline in ability to perform two tasks at the same time (divided attention)

0.05%

  • Exaggerated behavior
  • May have loss of small-muscle control (e.g., focusing your eyes)
  • Impaired judgment
  • Usually good feeling
  • Lowered alertness
  • Release of inhibition
  • Reduced coordination
  • Reduced ability to track moving objects
  • Difficulty steering
  • Reduced response to
  • emergency driving situations

0.08%

  • Muscle coordination become poor (e.g., balance, speech, vision, reaction time, and hearing)
  • Harder to detect danger
  • Judgment, self-control, reasoning and memory are impaired
  • Concentration
  • Short-term memory loss
  • Speed control
  • Reduced information processing capability (e.g., signal detection, visual search)
  • Impaired perception

0.10%

  • Clear deterioration of reaction time and control
  • Slurred speech, poor coordination, and slowed thinking
  • Reduced ability to maintain lane position and brake appropriately

0.15%

  • Far less muscle control than normal
  • Vomiting may occur (unless this level is reached slowly or a person has developed a tolerance for alcohol)
  • Major loss of balance
  • Substantial impairment in vehicle control, attention to driving task, and in necessary visual and auditory information processing

What is it used for?

BAC is usually determined by one of three tests: breath, urine, or blood. Blood testing is generally regarded as the most accurate method of estimating BAC but requires a trained professional to draw blood, which can be painful, time-consuming, and messy. Urine tests are considered the least accurate and tend to be used only when other tests are unavailable [4].

Breath testing is the most convenient, easy, and painless method of estimating BAC. It is the most common test performed by law enforcement officials, who use handheld fuel cell sensor breathalyzers to conduct roadside tests. These tests are nearly as accurate as blood tests and are considered admissible evidence in most court proceedings.

Alcohol Abuse

According to the Center for Disease Control and Prevention (CDC), alcohol abuse is when an individual develops a pattern of drinking that causes harm to their health, interpersonal relationships, or ability to work.

When a person experiences consequences from their drinking habits, they are abusing alcohol. For example, if a person is missing work or not fulfilling their daily responsibilities due to excessive drinking, they are abusing alcohol. Or, if a person is committing crimes and experiencing legal problems due to their drinking, or ruining their relationships with loved ones due to their drinking, they are abusing alcohol.

If a person continues to abuse alcohol, they will continue to cause harm to their physical health and more damage to their life. Moreover, alcohol abuse can lead to alcohol addiction, a chronic illness that is difficult for people to overcome.

Alcohol Addiction Treatment

The good news is that no matter how severe the problem may seem, most people with an alcohol use disorder can benefit from some form of treatment.

Research shows that about one-third of people who are treated for alcohol problems have no further symptoms one year later. Many others substantially reduce their drinking and report fewer alcohol-related problems.

Ultimately, there is no one-size-fits-all solution, and what may work for one person may not be a good fit for someone else. Simply understanding the different options can be an important first step.

Types of Treatment

Behavioral Treatments

Behavioral treatments are aimed at changing drinking behavior through counseling. They are led by health professionals and supported by studies showing they can be beneficial.

Also known as alcohol counseling, behavioral treatments involve working with a health professional to identify and help change the behaviors that lead to heavy drinking. Behavioral treatments share certain features, which can include:

  • Developing the skills needed to stop or reduce drinking
  • Helping to build a strong social support system
  • Working to set reachable goals
  • Coping with or avoiding the triggers that might cause relapse

Medications

Three medications are currently approved in the United States to help people stop or reduce their drinking and prevent relapse. They are prescribed by a primary care physician or other health professional and may be used alone or in combination with counseling.

The U.S. Food and Drug Administration (FDA) has approved three medications for treating alcohol dependence, and others are being tested to determine if they are effective:

  • Naltrexone can help people reduce heavy drinking
  • Acamprosate makes it easier to maintain abstinence.
  • Disulfiram blocks the breakdown (metabolism) of alcohol by the body, causing unpleasant symptoms such as nausea and flushing of the skin. Those unpleasant effects can help some people avoid drinking while taking disulfiram.

It is important to remember that not all people will respond to medications, but for a subset of individuals, they can be an important tool in overcoming alcoholism.

Mutual-Support Groups

Alcoholics Anonymous (AA) and other 12-step programs provide peer support for people quitting or cutting back on their drinking. Combined with treatment led by health professionals, mutual-support groups can offer a valuable added layer of support.

Relapse is common among people who overcome alcohol problems. People with drinking problems are most likely to relapse during periods of stress or when exposed to people or places associated with past drinking.

Enforcing the legal blood alcohol content limit is vital for public safety. It is always best to avoid driving after you have taken a drink. If someone is struggling with alcohol addiction and its intense and often dangerous alcohol withdrawal symptoms, they should consider inpatient rehab. We Level Up NJ addiction specialists are standing by to help.

Blood Alcohol Content
Know the danger signals and, if you suspect that someone has an alcohol addiction.

Sources:

[1] CDC – https://www.cdc.gov/motorvehiclesafety/impaired_driving/states.html#:~:text=Almost%20one%20in%20three%20traffic%20deaths%20in%20the,level%20%280.05%25%20or%200.08%25%2C%20depending%20on%20the%20state%29.

[2] CDC – https://www.cdc.gov/motorvehiclesafety/pdf/BAC-a.pdf

[3] NCBI – https://pubmed.ncbi.nlm.nih.gov/2348761/#:~:text=The%20mean%20blood%20alcohol%20concentration%20%28BAC%29%20in%20175,%20in%20many%20standard%20textbooks%20on%20forensic%20medicine.

[4] NIAAA – https://www.niaaa.nih.gov/publications/brochures-and-fact-sheets/understanding-dangers-of-alcohol-overdose