Calculating Blood Alcohol Content

1. Blood Alcohol Content (BAC) refers to the concentration of alcohol in the blood and is commonly used to determine whether a person has been drinking and the extent of their alcohol consumption.

2. BAC is usually measured in percentages (%), indicating the amount of alcohol (in milliliters) present in every 100 milliliters of blood.

3. Common BAC levels and their corresponding states of intoxication:

(1) 0.02%–0.05%: Mild relaxation and euphoria; attention may begin to wane.

(2) 0.05%–0.10%: Mood and behavior begin to be affected; coordination decreases and judgment is impaired.

(3) 0.10%–0.20%: Noticeable signs of intoxication, including slurred speech, unsteady gait, and prolonged reaction time.

(4) 0.20%–0.30%: Severe motor coordination impairment, possibly accompanied by vomiting and confusion.

(5) 0.30%–0.40%: May lead to unconsciousness; breathing and heart rate may be suppressed.

(6) 0.40% and above: May be life-threatening.

4. Note: Legal limits for driving under the influence vary by country, generally around 0.08%. In China, the limit is 0.02%; exceeding this constitutes driving under the influence.