Chevrolet 2007 Colorado Owner's Manual page 248

According to the American Medical Association,
a 180 lb (82 kg) person who drinks three 12 ounce
(355 ml) bottles of beer in an hour will end up
with a BAC of about 0.06 percent. The person
would reach the same BAC by drinking three
4 ounce (120 ml) glasses of wine or three mixed
drinks if each had 1-1/2 ounces (45 ml) of
liquors like whiskey, gin, or vodka.
It is 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,
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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. 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
will when each has the same number of drinks.
The law in most 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 have
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.