The amount of alcohol in a person’s body can be measured in terms of the "Blood Alcohol Concentration" or BAC level. At the time the survey was administered, most states set the BAC limit at .10, while the limit in 15 states was .08 in 1997.

This section examines the driving age public’s awareness and perceptions on the following BAC level topics:

Overall, more than four out of five (84%) persons age 16 to 64 have heard of blood alcohol concentration (BAC) levels. [Figure 20-A]. Non-Hispanic White persons of drinking age are significantly more likely to be aware of BAC levels than other racial groups, with 89% awareness. Fewer than three-fourths of those in other racial groups have heard of BAC levels [Figure 20-A]

The reported higher awareness of BAC levels by non-Hispanic White persons age 16 to 64 is substantiated in proven knowledge. More than half (53%) of those non-Hispanic White persons who are aware of BAC levels think they know the legal limit for their state, with almost six in ten (57%) of those being correct in their knowledge. [Figure 20-B]

Non-Hispanic Blacks are much less likely to say they know their state’s BAC limits (only 38% do) and are the least likely among those who purport knowledge to give a correct answer for their state, with just 40% having correct knowledge. [Figure 20-C]

About four in ten (44%) Hispanics say they know the legal BAC level for their state, while half (50%) are correct in their knowledge. [Figure 20-D]

Those who thought they knew their state’s BAC limit were asked how many beers in a two-hour period it would take someone their size to just reach their state’s legal limit.

Nearly two-thirds (63%) believe that it would take three or fewer beers within two hours to reach the state’s limit. An additional 17% feel that the limit would be reached at four beers. Just one in five (19%) feel that it would take 5 or more beers to reach the legal limit. The general public greatly under estimates the number of drinks to reach the legal BAC limit. Studies have shown that it would take an average 170-pound male five drinks within a two-hour period to reach a level of .08, while a 137-pound woman would reach this level with three drinks in two hours. Non-Hispanic Black and Hispanic persons who say they know about BAC limits, report a higher number of beers on average to reach the legal limit. [Figure 21-A]

Six in ten (61%) of those who have heard of BAC levels think that all or most drivers would be dangerous with a BAC at the legal limit. Those of American Indian/Eskimo descent are much less likely to feel that a majority of drivers would be dangerous. Asians are slightly less likely than Non-Hispanic Whites, Non-Hispanic Blacks or Hispanics to feel most or all drivers would be dangerous. [Figure 21-B]

On average, the driving age public age 16 to 64 believes that about 73% of all drivers who had consumed five beers in two hours would be dangerous on the road. One-third (33%) feel that all (100%) drivers would be dangerous after this many drinks. Non-Hispanic Blacks and Asian persons are the least likely to feel that all drivers would be dangerous. [Figure 21-C]

**Sample base for figures on this page:

New questions were added in the 1997 study to get a better understanding of the driving age public’s perceptions and acceptance of .08 BAC limits. Persons living in .08 BAC limit states who had heard of BAC levels were asked if the BAC limit in their state should stay at its current level, or be raised (more lenient) to .10. Those living in .10 BAC states were asked if their state’s level should be lowered (made stricter) to .08 or stay at the current level.

A majority of those aware of BAC levels support a BAC limit of .08 or stronger. More than half (56%) of those age 16 to 64 who have heard of BAC levels feel that their state’s BAC level should remain at, (for those in .08 states) or be lowered to (for those .10 states) a .08 BAC level. Eight of ten (80%) of these residents in current .08 states feel that the limit should remain at .08, or be made even stricter, while about 40% of those in .10 states feel that the limit should be lowered to .08. [Figure 22-A]

Non-Hispanic Whites are less likely than Non-Hispanic Blacks or Hispanics to feel that the BAC limit should be 0.08, with about 49% supporting a BAC limit of .08. In contrast, six of ten non-Hispanic Blacks (59%), and Hispanics (61% ) feel that the BAC level should stay at .08 (if they live in a .08 state) or be dropped to .08 (if they live in a .10 state). [Figure 22-B]