What Is Blood Alcohol Content?

Blood alcohol content, abbreviated as BAC, is the level of alcohol that is in a person’s blood after consuming alcohol. The level depends on how much alcohol the person drank, over what period of time, and the size of the person’s body. Additional factors that influence an individual’s BAC include metabolism, age/weight/gender, the strength of each drink, emotional state, physical health, and food intake. When alcohol enters the bloodstream, it travels throughout the body and reaches different organs, including the brain. This induces euphoria and the other pleasant effects of alcohol that most people want to achieve when drinking. The body can only metabolize about one drink per hour, so if someone consumes more than that or drinks quickly, the alcohol stays in the body until it is metabolized. This results in higher levels of intoxication. Frequently consuming alcohol can lead to tolerance, where someone will need to drink more to feel the same effects, but a high tolerance does not have an effect on blood alcohol content.

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The first 2 to 3 drinks will bring most people into the BAC range of .01 to .07. For a person who weighs 100 pounds, their BAC will be .06 after 2 drinks. A person who weighs 190 pounds will have .04 BAC after 2 drinks. At this level, a person will feel relaxed and less cautious. Inhibitions are lowered and emotions are intensified. Once a person reaches a BAC of .08, motor skills start to become impaired, balance becomes compromised, and the person starts to have trouble evaluating situations. They may also believe they are less intoxicated than they actually are. At this stage, driving becomes illegal.

.08 BAC is the legal limit to drive.

At .08, reflexes are slowed, muscle coordination is diminished, and eye coordination is weakened. If you are pulled over while driving at this level, you will likely be charged with the crime of driving under the influence (DUI). Once someone’s blood alcohol content reaches .14, the depressant effects of alcohol start to take effect, making them feel tired, anxious, or restless. It will become more difficult to walk or stand, and nausea may begin. A 100-pound person will likely reach .14 BAC after 3 or 4 drinks, while a 190-pound person will reach .14 BAC after about 5 or 6 drinks. This depends on how quickly they consumed the alcohol and if the person ate prior to drinking. When food is in the stomach, alcohol is absorbed more slowly.

A BAC of .20 will provoke feelings of confusion, disorientation, nausea and vomiting, and may potentially cause blacking out. Standing becomes difficult, and a person may even hurt themselves and become unable to feel pain. At .25 BAC, many people pass out. If a person is still conscious at this level, vomiting becomes very likely, as well as a complete loss of physical control. This can lead to asphyxiation if they lose consciousness and choke on their own vomit.

At .30 BAC, a person is at severe risk for alcohol poisoning and death. Medical attention should be sought at this level. A person who is not already unconscious will be unable to determine where they are or what they’re doing. Once they reach .35 BAC and above, their heart and lungs will slow down and they may fall into a coma. For most people, a blood alcohol content of .45 is fatal.

For most people, drinking to an extreme level of intoxication is never the goal and defeats the purpose of having a drink to relax. However, the more alcohol consumed, the less rational the thought process, leading many to continue drinking when they have really had enough. These lowered inhibitions are what often cause people to get behind the wheel of a car with confidence after drinking, putting themselves and others at risk.

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Driving Under The Influence

Every day in the United States, 29 people die in a motor vehicle crash involving an alcohol-impaired driver. In 2016, alcohol-related car crashes accounted for 28% of all traffic-related deaths. That same year, over 1 million drivers in America were arrested for driving under the influence. Police officers keep an eye out for people driving erratically so that they can pull them over and administer a sobriety test. Some of the signs that someone is drunk or drugged while driving are drifting in and out of lanes, tailgating, weaving, swerving, sudden stops or starts, almost hitting other cars, curbs, or objects, and slow responses to traffic signals.

When you know that someone is intoxicated, it can be difficult to stop them from driving their own car, but it is important to let them know in a non-confrontational way that you don’t want them to risk anyone’s life by driving unsafely. Offer to call the person a cab or a ride share service, or suggest they sleep over and pick up their car in the morning. Even if there is a risk of the person’s car getting towed, it is important to remember that the cost of a tow is around $200, while the average cost of a DUI is $6,500 after all of the fees are compounded.

Standard Field Sobriety Test

If a police officer pulls someone over on the suspicion of DUI, they may start by administering a standard field sobriety test (SFST). This process may include the horizontal gaze nystagmus test where the officer will ask the driver to follow a moving pen or flashlight with their eyes, as the officer moves it slowly from side to side. When someone is intoxicated, their eyes will jerk as they move, giving officers a clue that they may be drunk. This test is accurate in 77% of subjects. A walk and turn test is another common SFST, where the driver will take 9 steps in a straight line, turn on one foot, and take 9 steps in the other direction.

This test assess the driver’s balance and determines how well they understand and follow instructions. Another common SFST is a 1 leg stand test, where the driver stands with one foot off the ground and counts backwards from 1,001 until the officer tells them to stop. The officer then uses the next 30 seconds to see if the driver relies on their arms or hops to maintain balance, sways, or puts their foot down. If the driver fails any of these tests, they will likely be asked to take a breathalyzer test to measure their blood alcohol content.

How Does A Breathalyzer Work?

Each time you breathe after consuming alcohol, a little bit of the alcohol in your blood vaporizes, passes through your lungs, and exits your body out of your nose or mouth. A breathalyzer device can check someone’s blood alcohol content by measuring the amount of ethanol, the chemical compound in alcohol, in your breath. The larger amount of alcohol consumed, the larger amount of alcohol a person breathes out.

There are several types of breathalyzers, but most work in a similar fashion. Sometimes a breathalyzer test can result in an arrest, yet fail as evidence in court, while other test are sophisticated enough to result in a DUI conviction. A police officer administering a breathalyzer test tells the driver to blow into the machine for at least 3 seconds. This allows for deep lung air with the greatest concentration of alcohol to be tested. If there is still alcohol in the mouth, the test may read higher at first, but should stabilize and measure the deep lung air afterwards.

Can I Refuse A Breathalyzer Test?

A person detained on suspicion of DUI might think it is wise to refuse to take a breathalyzer test to avoid self-incrimination, but that is typically a worse option. When you get a driver’s license, there are implied consent laws that mean you have consented to a BAC test in order to legally drive. Although the laws vary by state, the refusal of a breathalyzer test may result in the immediate suspension of your license for up to 12 months and potentially jail time. In some states, judges are able to issue warrants that even mandate drivers to take breathalyzer tests. Most of the time, refusing to take a breathalyzer test has worse consequences than taking it.

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Get Help For An Alcohol Addiction

Even when the intention is to have 1 or 2 drinks, the way alcohol impacts decision making leads many people to drink far too much and have high blood alcohol content. Planning to not drink, or only having 1 drink, and then getting intoxicated regardless is a sign of an alcohol use disorder. If you or someone you know has trouble controlling how much they drink, call a treatment provider today to get answers about rehab options for overcoming alcohol addiction.

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If you or a loved one is ready to overcome an alcohol addiction, reach out today. Treatment providers can connect you with programs that provide the tools to help you get and stay sober.