What it means and how it saves lives

Blood Alcohol Concentration (BAC) is a means to measure the alcohol concentration in a driver’s blood. More to the point, it is a way to measure a person’s judgment abilities, reflexes and moods.

A rating of .03 for most people is little more than relaxed feeling with a bit of lightheadedness. Moving up the scale to a level between .04 to .06, drinkers begins to lose their inhabitations along with memory loss and impairment of reasoning.

At .07 to .09, impairment of balance, speech, vision, reaction time, and hearing occurs. The law in many states makes it illegal to drive with a BAC of .08. This particular level causes the person to experience a reduction in caution, judgment, and self-control.

Added to these dangerous conditions is the illusion you are functioning better than you really are. There is a significant impairment of judgment and coordination when reaching levels above .08. It is illegal to drive at levels of .08 and beyond in every state.

The Oklahoma City Police Department uses the following BAC chart as an educational tool. It helps new drivers to be more aware of the affects of alcohol and to what degree intoxication impairs their ability to drive responsibly.


5 Drinks
bac level indicator
bac level indicator
3 Drinks
4 Drinks
bac level indicator
3 Drinks
bac level indicator
bac level indicator
2 Drinks
2 Drinks
bac level indicator






Males 170 Lbs
Females 137 Lbs

The chart is not perfect and may not work for everyone since there are lots of variables that can affect BAC, including metabolism, weight, type and amount of food consumed and time. It is only as a guide to show how quickly a drinker can reach a state of intoxication that can impair driving abilities. The numbers in red indicate levels that are considered illegal to drive in all states.

Understanding this chart and what it explicates can save a life. Just knowing the levels of your BAC and the number of drinks that it takes to reach unsatisfactory levels for driving is life-saving information.

According to a 2004 study by Hingson and Kenkel, 6000 people died in alcohol related accidents during 2002 in the United States. Another report stated over eighteen million Americans fall within the diagnostic criteria of alcohol abuse or alcoholism.

More about BAC

Learn about alcohol addiction.