Understanding Blood Alcohol
Level
Blood
alcohol level (BAL) refers to the ratio of alcohol
to blood in the bloodstream. It also accurately reflects
the level of alcohol in the entire body. BAL, also
known as blood alcohol concentration (BAC), is represented
as a percentage. Heres an analogy which may
help you understand what those numbers represent.
Picture thisa shelf with 10,000 compartments.
Each compartment is filled with a drop of blood. If
I replace one drop of blood with one drop of alcohol,
the shelf now has a BAL of .01 percent. If I replace
two drops of blood with two drops of alcohol, the
shelf now has a BAL of .02 percent. If I replace ten
drops of blood with ten drops of alcohol, then the
shelf has a BAL of .10 percent.
Previously a BAL of .10 percent was considered legally
drunk in most states. National legislation in the
year 2000 has proposed a national BAL limit of .08
percentand rightly so. After all, ongoing research
continues to indicate a clear, direct relationship
between increased BAL and increased risk for automobile
crashes, serious injury and death.
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Estimating
BAL
To
estimate Blood Alcohol Level (also known as Blood
Alcohol Concentration - BAC):
- move down the Drink/Weight Index chart below
to the number of drinks and your gender.
(A drink equals a 12 oz. regular beer, 1 oz. shot
of 100 proof liquor, 1.5 oz. shot of 80 proof liquor,
or 4 oz. glass of regular table wine)
- move across the chart to your weight to arrive at
your Drink/Weight Index
- subtract .01% from the Drink/Weight Index
for each hour from the start of
the drinking period to the point in time you want
to measure the BAL.
DRINK/WEIGHT
INDEX CHART |
#
OF DRINKS
CONSUMED/SEX |
WEIGHT |
|
|
100 |
120 |
140 |
160 |
180 |
200 |
220 |
240 |
1 |
Male |
.04 |
.04 |
.03 |
.03 |
.02 |
.02 |
.02 |
.02 |
Female |
.05 |
.04 |
.04 |
.03 |
.03 |
.03 |
.02 |
.02 |
2 |
Male |
.09 |
.07 |
.06 |
.05 |
.05 |
.04 |
.04 |
.04 |
Female |
.10 |
.08 |
.07 |
.06 |
.06 |
.05 |
.05 |
.04 |
3 |
Male |
.13 |
.11 |
.09 |
.08 |
.07 |
.07 |
.06 |
.05 |
Female |
.15 |
.13 |
.11 |
.10 |
.08 |
.08 |
.07 |
.06 |
4 |
Male |
.17 |
.15 |
.13 |
.11 |
.10 |
.09 |
.08 |
.07 |
Female |
.20 |
.17 |
.15 |
.13 |
.11 |
.10 |
.09 |
.09 |
5 |
Male |
.22 |
.18 |
.16 |
.14 |
.12 |
.11 |
.10 |
.09 |
Female |
.25 |
.21 |
.18 |
.16 |
.14 |
.13 |
.12 |
.11 |
6 |
Male |
.26 |
.22 |
.19 |
.16 |
.15 |
.13 |
.12 |
.11 |
Female |
.30 |
.26 |
.22 |
.19 |
.17 |
.15 |
.14 |
.13 |
7 |
Male |
.30 |
.25 |
.22 |
.19 |
.17 |
.15 |
.14 |
.13 |
Female |
.36 |
.30 |
.26 |
.22 |
.20 |
.18 |
.16 |
.15 |
8 |
Male |
.35 |
.29 |
.25 |
.22 |
.19 |
.17 |
.16 |
.15 |
Female |
.41 |
.33 |
.29 |
.26 |
.23 |
.20 |
.18 |
.16 |
9 |
Male |
.39 |
.35 |
.28 |
.25 |
.22 |
.20 |
.18 |
.16 |
Female |
.46 |
38 |
.33 |
.29 |
.26 |
.23 |
.21 |
.19 |
10 |
Male |
.39 |
.35 |
.28 |
.25 |
.22 |
.20 |
.18 |
.16 |
Female |
.51 |
.42 |
.36 |
.32 |
.28 |
.25 |
.23 |
.21 |
11 |
Male |
.48 |
.40 |
.34 |
.30 |
.26 |
.24 |
.22 |
.20 |
Female |
.56 |
.46 |
.40 |
.35 |
.31 |
.27 |
.25 |
.23 |
12 |
Male |
.53 |
.43 |
.37 |
.32 |
.29 |
.26 |
.24 |
.21 |
Female |
.61 |
.50 |
.43 |
.37 |
.33 |
.30 |
.28 |
.25 |
13 |
Male |
.57 |
.47 |
.40 |
.35 |
.31 |
.29 |
.26 |
.23 |
Female |
.66 |
.55 |
.47 |
.40 |
.36 |
.32 |
.30 |
.27 |
14 |
Male |
.62 |
.50 |
.43 |
.37 |
.34 |
.31 |
.28 |
.25 |
Female |
.71 |
.59 |
.51 |
.43 |
.39 |
.35 |
.32 |
.29 |
15 |
Male |
.66 |
.54 |
.47 |
.40 |
.36 |
.34 |
.30 |
.27 |
Female |
.76 |
.63 |
.55 |
.46 |
.42 |
.37 |
.35 |
.32 |
Remember!!!
This is only an estimation based on an average metabolic
rate. Differences in metabolic rates, gender, types
of drinks, food in the stomach etc. can contribute
to substantial differences in your Blood Alcohol Levels.
Also, there may be slight differences (.01 - .03)
between the various BAL Charts that are available
to you.
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Other
Factors Impacting BAL
and Impairment
In
addition to the amount of alcohol consumed, the speed
at which it is consumed, and your tolerance, here
are a number of other factors that will also affect
how quickly and to what degree you will get impaired
if you choose to drink:
- Food in the stomach will slow the absorption of
alcohol into the bloodstream and delay impairment.
The type of food ingested (carbohydrate, fat, protein)
has not been shown to have a measurable influence
on BAL. However, we do know that the larger the meal
and the closer the time between eating and drinking,
the lower the peak blood alcohol concentration. Studies
have shown reductions in peak blood alcohol concentration
(as opposed to those of a fasting individual under
otherwise similar circumstances) of between 9 percent
and 23 percent.
- Alcohol mixed with carbonated beverages such as
Coca-Cola or Seven Up will be absorbed more quickly
into the bloodstream. This is also true for champagne
and wine coolers.
- Women who are pre-menstrual and sometimes those
on birth control pills tend to get more impaired more
quickly.
- Strong emotionsanger, fear, lonelinesstend
to hasten impairment.
- If you are tired, sick or just getting over an illness,
you tend to get more impaired more quickly.
- Mixing alcohol with other drugs often leads to increased
impairment in a shorter period of time.
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