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Breath alcohol test

Breath alcohol test

Overview

The breath alcohol test measures the amount of alcohol in the blood by testing exhaled air. The test is performed by blowing into a breath machine 15 minutes after alcohol consumption. The test determines how much alcohol it takes to raise the blood-alcohol level to a dangerous level.

Review Date 4/16/2022

Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.