Everyone knows that drinking and driving is a bad thing, but do we all really understand the problem? Maybe not, because drinking and driving (or driving under the influence of alcohol) is a complex problem.
The only simple part of the drinking and driving problem is this: People die when other people decide to drink and drive. It’s that simple and that horrible.

16,653 people died in alcohol-related crashes in 2000 (the last year for which data are available). Also 2000, about 14% of 16-20-year-old drivers and 27% of drivers of 21-24-year-old drivers who were involved in fatal crashes were legally drunk.

Any amount of alcohol can make driving dangerous. That’s why you should think of drinking and driving as “driving under the influence” (DUI) instead of “drunk driving.” Someone does not have to be “drunk” in order for his or her driving and judgment skills to be dangerously affected.

If you are under 21, any amount of alcohol in your system is “legally intoxicated.” For people aged 21 and over, the legal definition of intoxication is either .10% blood alcohol or .08% blood alcohol, depending on which state the person was driving in.

The problem is that hardly anyone is able to measure his or her own blood alcohol concentration. In fact, a lot of people do not really understand what blood alcohol concentration means.

Blood Alcohol Concentration (BAC)

Blood Alcohol Concentration, or BAC, measures the amount of alcohol in a person’s body compared to the amount of blood in his or her body.

In most states, a person is considered “legally intoxicated (legally drunk)” when his or her BAC reaches .10%. That means that for every ONE THOUSAND units of blood in a person’s body, he or she has ONE unit of alcohol.

In many other states and in Canada, the limit is more strict: For every TEN THOUSAND units of blood, a person who has EIGHT units of alcohol in his or her body is legally intoxicated.

Click here to see our BAC calculator ( will appear in a pop-up window )