In Germany, public buildings including schools use a standardized DIN fire alarm signal, often called Brandalarm, designed to be heard over noise and recognized instantly as an evacuation warning. Clips of that tone circulate online under short titles like Schule because students film drills and creators reuse the recording for pranks and edits. Its harsh, official sound is funnier and more alarming than a generic bell, so it keeps appearing whenever a video needs an authentic European school alarm rather than a cartoon effect.