Effects of Drinking Based on Blood Alcohol Concentration

How Alcohol Can Affect the Body and Driving at Different Levels

The National Highway Traffic Safety Administration (NHTSA) is running a number of campaigns to help remind people that driving while impaired is not only dangerous but it can turn deadly. According to NHTSA, a person dies every 50 minutes in a drunk-driving crash. In 2018, 10,511 people were killed in drunk driving crashes in the United States. Fatalities resulting from driving under the influence are completely preventable.

In an effort to help people understand how even low amounts of alcohol can affect a person’s reaction time and driving abilities, NHTSA has released information about the typical effects of alcohol at different levels.

At twice the legal limit, .15 blood alcohol concentration (BAC), a person may experience major loss of balance and less muscle control, they may vomit and will have substantial impairment in vehicle control.

A BAC of .10 percent can result in slurred speech, slower reaction time, and may affect a person’s ability to think quickly. At this level is not uncommon for a person to have a decreased ability to stay within a lane or brake appropriately.

Blood alcohol concentration of .08 percent or higher is considered over the legal limit in most states (Utah recently reduced their legal limit to .05). With a BAC of .08 a person may have reduced reaction time, may be unable to detect danger, and may have impaired judgment and self-control.

Even with a blood alcohol concentration of .05 percent, a person may have impaired judgment and reduced coordination. This can result in difficulty steering and a “reduced response to emergency driving.”

Consuming any amount of alcohol can result in harmful effects. According to NHTSA, a person with a blood alcohol concentration of .02 percent may experience some loss of judgment and a decline in visual functions.

Read more about the typical effects of blood alcohol concentration and the predictable effects on driving on NHTSA’s drunk driving website.