### Question
How is the term alcohol concentration defined?


### Answer
The term **alcohol concentration** is defined in *23 U.S.C. § 164* as the following:

> grams of alcohol per 100 milliliters of blood or grams of alcohol per 210 liters of breath

#### Citation:
  - *23 U.S.C. § 164*
  - Heading: **CHAPTER 1-FEDERAL-AID HIGHWAYS > SUBCHAPTER I-GENERAL PROVISIONS**

