How Is Your BAC Calculated? [Infographic]

How Is Your BAC Calculated

Arizona classifies certain DUI offenses based on blood alcohol content (BAC), which is a measure of the percentage of alcohol in a person's bloodstream.

For example, a standard DUI is classified as driving a vehicle with a BAC of 0.08% or more, whereas an extreme DUI is classified as driving with a BAC of 0.15% or higher.

Given BAC's importance under Arizona law, it is important to understand what BAC is and how it is calculated in Arizona.

How BAC Is Calculated BAC is calculated by dividing the mass of ethanol (alcohol) in the body by 100ml of blood, which is then converted into a BAC percentage.

In Arizona, for example, the 0.08% percentage needed for a standard DUI means that there was 8 grams of alcohol present in 100ml of the person's bloodstream when they were tested.

However, Arizona law also allows drivers to be charged with a DUI if they are "impaired to the slightest degree".

Effectively, this means a driver can be charged with a DUI if they were impaired at all while driving.

Factors Affecting BAC and Impaired Driving Impaired driving and/or a high BAC percentage is most affected by the following five factors: • How much alcohol is consumed • How fast alcohol was consumed • Body weight • Time passed since drinking • The person's gender (typically, women become intoxicated faster than a man of the same weight who drank the same number of drinks within the same timeframe)

If you or someone you love has been charged with a DUI, contact an attorney who has experience handling DUI cases.