Chevrolet 2002 Tahoe Owner's Manual page 215

It's the amount of alcohol that counts. For example, if
the same person drank three double martinis (3 ounces
or 90 ml of liquor each) within an hour, the person's
BAC would be close to 0.12 percent. A person who
consumes food just before or during drinking will have a
somewhat lower BAC level.
There is a gender difference, too. Women generally have
a lower relative percentage of body water than men.
4-4
Since alcohol is carried in body water, this means that
a woman generally will reach a higher BAC level than
a man of her same body weight when each has the
same number of drinks.
The law in an increasing number of U.S. states, and
throughout Canada, sets the legal limit at 0.08 percent.
In some other countries, the limit is even lower.
For example, it is 0.05 percent in both France and
Germany. The BAC limit for all commercial drivers
in the United States is 0.04 percent.
The BAC will be over 0.10 percent after three to six
drinks (in one hour). Of course, as we've seen, it
depends on how much alcohol is in the drinks, and
how quickly the person drinks them.
But the ability to drive is affected well below a BAC of
0.10 percent. Research shows that the driving skills of
many people are impaired at a BAC approaching
0.05 percent, and that the effects are worse at night.
All drivers are impaired at BAC levels above 0.05 percent.
Statistics show that the chance of being in a collision
increases sharply for drivers who have a BAC of
0.05 percent or above. A driver with a BAC level of
0.06 percent has doubled his or her chance of having a
collision. At a BAC level of 0.10 percent, the chance of
this driver having a collision is 12 times greater; at a level
of 0.15 percent, the chance is 25 times greater!