Luchtalarm is the Dutch air raid siren system, tested across the Netherlands on the first Monday of each month at noon, so the rising wail is instantly familiar to Dutch listeners. Online, an exaggerated extreme version became a meme sound, shared on soundboards and in short videos where any minor problem gets treated like a national emergency. Its humour comes from that contrast between a real public warning and a trivial trigger, and it remains popular for reaction edits, gaming clips and alarm or buzzer style jokes.