|MadSci Network: Chemistry|
Hydrofluoric acid is, like hydrochloric acid, a gas (HF, or similarly HCl) dissolved in water. The boiling point of HF (liquid) is approximately 20 degrees celsius (68 degrees farenheit). Therefore, if your sample has been dry and at room temperature for more than a few hours, I would venture that all of the HF that may have been left on it has evaporated, and you would be perfectly safe washing it or exposing it to water.
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