We get it, alcohol interlocks aren't the easiest things to operate. We try to make them as straightforward as possible, but some government requirements and technology limitations mean we can still get the occasional false positive. The good news is that for the most part, these are completely avoidable. Here's a refresher course of the steps you should take to help you toe the line and get through your interlock program.
1: Don't put any substances in your mouth (except water) in the ten minutes before doing a breath test and at all times when driving. This means food and drink, but also includes other substances that catch people out like toothpaste, breath mints and mouthwash.
2: Always have a bottle of plain water on hand. Before every test take a sip of water to rinse your mouth of any trace of alcohol. This ensures that what is being tested is your breath, and not the sourdough you ate for breakfast.
3: As long as the engine is running, watch out for random retests. It doesn't matter if you're just about to turn the engine off, or if you've arrived at your destination, you must take every requested test. If you miss any tests it goes on your record as a violation of your program.
4: Don't leave your car running when you're not in it. So long as the engine is on, the device will continue to request retests regardless of whether you're present or not. If you miss a random re-test it's still a violation, even if you had no idea it was asking.
5: Only let someone you trust drive your car, and make sure they are as familiar with the rules as you are. If they commit any violations you'll be the one responsible. Drill it into their heads that if they stuff up, you pay the consequences.
6: Your alcohol tolerance can change over time. Even if you used to recover from a night of heavy drinking by the next morning, your tolerance might have changed since then. Understand your limits, and keep in mind that alcohol can stick around in your body longer than you expect.
7: Don't use your interlock device as a breathalyser. Every failed attempt will be on your record and affect your program, so don't even try to drive if you're unsure. A personal breathalyser device can be a good option to check your BAC before deciding whether you're okay to get in the car or not. It's nowhere near as accurate as your interlock in measuring BAC, but so long as your personal device is a fuel cell breathalyser, and is sent away for calibration regularly, it gives a pretty good indication.
Follow all these steps and you'll be able to focus on what really matters, separating your drinking from your driving.