Blood Alcohol Level Law and Legal Definition

Blood Alcohol Level is the amount or level of alcohol present in an individual's blood. Legal limits of blood alcohol levels vary from state to state. BAL is commonly used as a metric of calculation for medical and legal purposes.

There are many different units in use around the globe for defining blood alcohol concentration. Each is defined as either a mass of alcohol per volume of blood or a mass of alcohol per mass of blood.

The following is an example of a state statute (Rhode Island) defining the term:

"Blood alcohol level" means the percent by weight of alcohol in a person's blood, based upon milligrams of alcohol per one hundred (100) cubic centimeters of blood. [R.I. Gen. Laws § 46-22.2-2].