Blood Alcohol Test - Meaning of the Numbers

Blood alcohol content (BAC) is an indicator to measure degree of intoxication for legal or medical purposes. It is usually measured by the volume of alcohol in a unit volume of blood. For example, American BAC 0.10% means 100 mg of alcohol per dl of blood.

The test is also named Ethanol, or Ethyl Alcohol.

Unit of measure conversion

BAC % = BAC value (mg/dl) / 1000 *1%
For example, when BAC value is 25 mg/dl, BAC % is 25/1000*1% = 0.025%

BAC equal to or above 0.8% is legal intoxication in all states.

Effect of alcohol

BAC (%) BAC (mg/dl) Behavior Affect
0.010–0.029 10 – 29 averagely normal feeling slight effect may be detected in certain special tests
0.030–0.059 30 – 59 mild euphoria can’t focus
decreased suppression
0.06–0.09 60 – 90 feeling numb ability of reasoning
less self-conscious ability of perception
peripheral vision
glare visual recovery
0.10–0.19 100 – 190 over-expression conditioned reflex
angry or sad reaction time
noisy rough motion control
can’t speak clearly
0.20–0.29 200 – 290 sluggish eyes severe impairment in movement  ability
cant’ understand unconscious
may fall into a coma blank memory
0.30–0.39 300 – 390 central nervous system depression bladder function
May cause death Insufficient lung ventilation
0.40–0.50 400 – 500 incapacity breathe
coma pulse
may cause death alcoholic nystagmus
>0.50 >500 high risk alcoholism
* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.