It was a brisk autumn evening in Berlin, and I found myself in a brightly lit car park, watching as a friend submitted to a breathalyser test before getting behind the wheel. The tension was palpable as he exhaled into the device. Instantly, the small gadget registered his blood alcohol level, and, after what felt like an eternity, a green light flashed—he was good to go. It sparked my curiosity: how exactly do these breathalyser systems integrate with modern vehicles to create safer roads? This question led me down a rabbit hole into the fascinating world of automotive safety technology.