Structure fire tones are the alert signals used by fire departments and dispatch systems before announcing a building fire response over radio or station speakers. Variations exist by agency, so the exact tone pattern can differ from place to place. Online, these clips spread through firefighter content, emergency services edits, and comedic videos where a normal moment suddenly gets treated like a full emergency. The sound remains popular because it is instantly recognizable, urgent, and easy to use as a dramatic cue.