Can burping or acid reflux affect a breath test?

Both bring stomach contents into the mouth, and alcohol in the mouth can push a reading above what's actually in the blood. That's the entire reason the observation period exists.

What that means practically is narrower than most people hope. A documented reflux condition doesn't invalidate a test on its own. It becomes meaningful when it lines up with something else in the record — an observation period that was short or interrupted, a visible or audible event on the booking video, a gap between the two breath samples, or an officer who never asked about medical conditions.

The analysis is a comparison, not a single fact. Medical history, the observation period video, the instrument's own data, and where necessary expert testimony, all read against each other.

If you have a diagnosed reflux condition, get the records. A prescription predating the arrest carries weight that a description after the fact does not.