| Many factors affect an individual's
absorption of alcohol. These include weight, sex (a higher
proportion of a woman's body weight is in fat and fat absorbs
less alcohol than muscle tissue), amount of food in the
digestive track, and time spent drinking (and the corresponding
rate of elimination).
BAC levels and the number of
"typical" drinks required to reach them can be roughly
estimated. After 4 drinks in one hour, a male of 160 pounds
will reach a BAC of .07% and a female of 120 pounds will
reach a BAC of .08%. The following is a breakdown of skill
set vs blood alcohol levels
|
BAC Level
|
Impairment
|
|
.03 BAC
|
Choice reaction time impaired |
|
.04 BAC
|
Simple Reaction time
Emergency Response |
|
05 BAC
|
Tracking
divided attention
coordination
comprehension & eye movement |
|
.08 BAC
|
Concentration attention
speed control
braking
gear changing
lane tracking |
What is the Risk?
The risk of being in a crash begins to rise between .04% and
.05% BAC, and increases rapidly thereafter. By the time a
driver reaches a BAC of .06% he or she is twice as likely to
be involved in a fatal crash as a non- drinking driver.
Additional alcohol increases the
chance of a fatal crash even more. A driver with a BAC of
.10% to .14% is about 50 times as likely to be in a fatal
crash as a non-drinking driver. The rate goes up as the BAC
rises.
Know your personal limit of moderation
It is important to know the many factors affect impairment,
they are:
-Gender-
Because of differences in body composition and chemistry,
males and females are affected differently by alcohol. Men
generally have more muscles tissue and women more fatty
tissue.
-Fatty Tissue-
Fatty tissue has a smaller blood supply than muscle tissue
so more of the alcohol goes into the bloodstream. The result
is that when a man and woman of equal weight drink equal
amounts of alcohol, the alcohol concentration level will be
higher in the woman.
-Time-
The number of hours a person drinks affects BAC. The body
slowly eliminates alcohol as follows: oxidation by the liver
(95%), breath (2%), urine (2%), and perspiration (1%). The
liver's rate of oxidation is constant and cannot be
increased by drinking coffee, physical activity, or by
taking cold showers. The body eliminates about one standard
drink an hour.
-Strength-
The strenght of drink as mentioned above, all drinks are not
created equal. A mixed drink usually has more than 1-1/2 oz
of alcohol and the alcohol in different beers can vary as
much as 40%.
-Age-
This factors is rarely considered in discussion of BAC,
but it is important. The human body develops less tolerance
to alcohol with aging. This is due to a gradual change or
slowing down of the body's metabolic rate. In addition, the
ratio of body fat to muscle increases with age. As a result,
the same amount of alcohol intake per body weight consumed
by older people (after 55) can result in higher alcohol
concentration levels and the effects of alcohol last longer.
Age and drinking is a factor for young people. They become
involved in fatal crashes at significantly lower BAC than
adults. Their alcohol use disrupts their novice driving
skill at lower BAC levels.
What is the Risk?
The risk of being in a crash begins to rise between .04% and
.05% BAC, and increases rapidly thereafter. By the time a
driver reaches a BAC of .06% he or she is twice as likely to
be involved in a fatal crash as a non- drinking driver.
Additional alcohol increases the chance of a fatal crash
even more. A driver with a BAC of .10% to .14% is about 50
times as likely to be in a fatal crash as a non-drinking
driver, and 380 times greater at a .15 and above
Information from the National Highway Safety Administration
and Nationwide
Insurance and the Minnesota Driver's Manual
|
