The sound comes from Napo in Danger Chemicals, part of the long running Napo safety film series that uses mime and slapstick to teach workplace hazards without dialogue. In this closing scene Napo mishandles chemicals and is blasted unconscious, a visual lesson about labels, storage and protective equipment. Clips of Napo have circulated widely in schools, training sessions and later on soundboards, where the explosion was isolated because it works without context. Its continued use comes from that mix of official safety cartoon and pure meme timing.