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 5/14/2016
Updated by: Jesse Borke, MD, FACEP, FAAEM, Attending Physician at FDR Medical Services / Millard Fillmore Suburban Hospital, Buffalo, NY. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.