User Guide

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.
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 many
U.S. states sets the legal limit at a BAC
of
0.10 percent. In a growing number of U.S. states, and
throughout Canada, the limit is
0.08 percent. In some
other countries, it’s even lower. 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!
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