Fire alarms in German schools use a standardised DIN warning tone meant to be heard clearly in every classroom, corridor and stairwell during an evacuation. Online, recordings of this alarm spread as a prank sound, shared in videos and soundboards alongside similar alerts like a smoke detector beep. Its harsh, official tone makes even a short clip feel real, which is why creators use it for fake drills and school jokes. Unlike a generic siren, listeners who know German schools recognise the pattern straight away.