It was supposed to be a fun trip. Four of us, a six-hour sleeper train across the province, tickets booked weeks in advance. We’d planned everything—snacks, playlists, a deck of cards. The excitement of a weekend away with old friends. The kind of trip you look forward to for months.

Last weekend, I did something a little weird. I packed my camping gear, threw some instant noodles in my bag, and grabbed my Mini All-in-One Air Quality Monitor. My friends laughed when they saw it. "You're bringing that to the woods? To check what, the trees?"

It started like any other Saturday hangout. Three of us sprawled across my living room couch, takeout containers scattered on the coffee table, some reality show playing background noise. We'd been friends since college—the kind where you don't need to impress anyone anymore.

Instead of guessing or relying on “I feel fine,” we pass the breathalyzer around between songs. It only takes a few seconds. A steady breath, a short wait, and the BAC number appears clearly on the screen. No drama, no judgment — just a number that helps you decide what to do next.