Blood alcohol content (BAC) levels represent the percentage of a person’s blood that is concentrated with alcohol. Having a BAC of .10 means that at least .1% of your bloodstream is composed of alcohol. In many states, the legal BAC limit to operate a motor vehicle is below 0.08. Anything higher than 0.08 is considered legally impaired and can result in a DUI.
Your blood alcohol content level measures the amount of alcohol in your blood that is traveling through your entire body, to every organ, including your brain. According to AwareAwakeAlive, having a BAC between 0 and 0.05% represents mild impairment and can include the following:
- Mild speech, memory, attention, coordination, and balance impairments.
- Sleepiness and perceived beneficial effects, such as relaxation.
Keep in mind, as blood alcohol content increases, so do impairment. Increased impairment levels begin to occur between 0.06% and 0.15% BAC, and can include:
- Moderate memory impairments.
- Vomiting typically occurs at this level — right around .120%
- Significant impairments in all driving skills.
- Perceived beneficial effects of alcohol, such as increased relaxation feelings.
- Speech, attention, coordination, and balance further impaired.
- Increased risk of aggression in some people.
Severe impairment occurs between 0.16% and .30%, and can include:
- Speech, memory, coordination, attention, reaction time, and balance are significantly impaired.
- Loos of consciousness in some people.
- Judgment and decision-making dangerously impaired.
- Vomiting and other signs of alcohol poisoning.
Unfortunately, many people continue to drink even past severe BAC levels, subsequently reaching life-threatening levels. A life-threatening BAC level is anywhere from 0.31% and above, and can include:
- Loss of consciousness.
- Significant risk of death in the majority of drinkers due to suppression of vital life functions.
- The danger of life-threatening alcohol poisoning.
Though the legal limit is .08%, driving skills can be significantly affected after just a few drinks. Even 1 drink can impair someone who weighs around 120 pounds, giving them a .04% to .05% BAC level. Similarly, it takes a 200-pound man, on average, about 4 drinks to reach a BAC level of .08% and takes only 1.5 to 2 drinks for a 100-pound person to reach that level of impairment.
Drinking and driving remain a serious problem in the United States. No matter what, even if you think you have a full understanding of BAC levels, should operate a vehicle after drinking. Call a cab, get a car breathalyzer, or simply just stay where you are — do not drink and drive. Ever.
Understanding Blood Alcohol Content (BAC)