Education

Blood Alcohol Concentration

 

MALE BLOOD ALCOHOL CONCENTRATION GUIDE

Number of
Drinks Per Hour
PERCENT OF ALCOHOL IN BLOODSTREAM
 
BODY WEIGHT IN POUNDS
110
120
140
160
180
200
220
240
0
ONLY SAFE DRIVING LIMIT
1
.04
.03
.02
.02
.02
.02
.02
.02
Driving
Skills
IMPAIRED
2
.08
.06
.05
.05
.04
.04
.03
.03
3
.11
.09
.08
.07
.06
.06
.05
.05
4
.15
.12
.11
.09
.08
.08
.07
.06
5
.19
.16
.13
.12
.11
.09
.09
.08
LEGALLY DRUNK IN IOWA and most states
6
.23
.19
.16
.14
.13
.11
.10
.09
7
.26
.22
.19
.16
.15
.13
.12
.11
8
.30
.25
.21
.19
.17
.15
.14
.13
9
.34
.28
.24
.21
.19
.17
.15
.14


FEMALE BLOOD ALCOHOL CONCENTRATION GUIDE

Number of
Drinks Per Hour
PERCENT OF ALCOHOL IN BLOODSTREAM
 
BODY WEIGHT IN POUNDS
100
120
140
160
180
200
220
240
0
ONLY SAFE DRIVING LIMIT
1
.05
.04
.03
.03
.03
.02
.02
.02
Driving
Skills
IMPAIRED
2
.09
.08
.07
.06
.05
.05
.04
.04
3
.14
.11
.10
.09
.08
.07
.06
.06
4
.18
.15
.13
.11
.10
.09
.08
.08
LEGALLY
DRUNK IN
IOWA and
most states
5
.23
.19
.16
.14
.13
.11
.10
.09
6
.27
.23
.19
.17
.15
.14
.12
.11
7
.32
.27
.23
.20
.18
.16
.14
.13
8
.36
.30
.26
.23
.20
.18
.17
.15
9
.41
.34
.29
.26
.23
.20
.19
.17


Note: The data on the charts is indicative of only one hour of alcohol consumption. Consuming multiple drinks per hour over a period of more than one hour would render a person’s Blood Alcohol Content significantly higher than the data listed on the chart for one hour of consumption.

 

IMPAIRED DRIVING

BAC %

DRINKS CONSUMED
EFFECTS
Male
Female

0.02%

1
1
Ability to track moving objects and do tasks requiring divided attention may suffer.

0.05%

2 to 3
1 to 2
Thought, judgment and restraint more lax. Steering errors increase. Vision impaired.

0.08%

3 to 4
2 to 4
Legal limit in most states. Drivers are 3 to 4 times more likely to crash than a sober driver. Movements are clumsy. Reaction time slows more.

0.10%

3 to 5
2 to 5
Drivers are 6 times more likely to crash. Movements are clumsy. Reaction time slows even more.

0.15%

4 to 7
3 to 7
Crashing is 25 times more likely. Reaction time increasingly affected especially in divided tasks. Field of vision narrows.
One drink =
5 oz. glass of 12% wine, or
12 oz. glass of 5% beer, or
1.5 oz. 80 proof spirits, or
0.8 oz. 151 proof spirits

Figures contained in the charts are averages, BAC and effects of alcohol on individuals vary widely.