[turretslug]

Like PTFE, synthetic rubbers like Viton can decompose to form hydrofluoric acid under extreme heat- I was warned not to handle components from fire-damaged vehicles as things like door seals and engine component gaskets could produce HF residues, with similarly grim bone-eating consequences as outlined above.

Kalee20's account reminded me that (whilst not a smoker myself), we were warned not to smoke whilst using halogen-containing cleaners, such as trichloromethane ("trike") and quite a few others, as the vapour could be decomposed by contact with hot ash into phosgene (carbonyl chloride).