Seems like it would be easy to defeat.
It also seems like false positives would be a problem.
Can't start your car because you rinsed with mouthwash after you brushed your teeth before you left the house? Used hand sanitizer? Oops. Sucks to be you. Guess you're gonna be late to work.
There's even some medical conditions such as gastroesophageal reflux disease (GERD), acid reflux, hiatal hernia and heartburn can lead to false results on an alcohol breath test.