Not a blood test, and not a generic label for every breath machine police use. An Intoxilyzer is a brand or model of breath-testing instrument that estimates a person's blood alcohol concentration (BAC) by analyzing alcohol in deep lung breath. It uses infrared technology to measure alcohol vapor and then converts that reading into an estimated BAC. In plain terms, it is a machine meant to show how much alcohol is in someone's system without drawing blood.

That matters because an Intoxilyzer result can become key evidence in a DUI case, but the number is only as reliable as the testing process. Calibration, maintenance, observation time before the test, operator training, and whether the person burped, vomited, or had something in the mouth can all affect the reading. Those details may be challenged as part of the admissibility or accuracy of the test.

In Idaho, DUI cases often turn on whether the state can prove a BAC of 0.08 or higher under Idaho Code § 18-8004 (2024). Idaho's implied consent law, Idaho Code § 18-8002 (2024), also allows consequences for refusing evidentiary alcohol testing. In fast-growing areas like Ada County, where traffic stops are common, Intoxilyzer results often play a central role in arrests, license suspensions, and disputed injury claims after a crash.