Dilute hydrofluoric acid solutions are used in some biological staining procedures. Hydrofluoric acid solutions are clear and colorless with a density similar to that of water. The most widely known property of HF is its ability to dissolve glass. Upon reaction with metals, explosive hydrogen gas may be formed. Use and store HF in polyethylene, polypropylene, Teflon, wax, lead or platinum containers.
Fluoride ions are both acutely and chronically toxic.
Acute effects of HF exposure include extreme respiratory irritation, immediate and severe eye damage and pulmonary edema. HF solutions will cause immediate, severe, penetrating burns. Exposure to less concentrated solutions may have equally serious effects, but the appearance of symptoms can be delayed for up to 24 hours. If you are exposed to hydrofluoric acid seek medical attention immediately, even if you do not feel pain. PPE is not a substitute for safe work practices.