Hydrofluoric acid is one of the nastiest chemicals around, despite being one of the weaker acids.  It’s one of the most tissue destructive organic acids; read, something you really do not want to get on yourself.

The question is: how to treat it?  As with certain other tissue-destructive chemicals – phenol springs to mind – water is not the best solution, or even a particularly good solution.  What water does, in the main, is dilute acids and other contaminants down in the hope of getting it down to below a dangerous level.  The problem is that any acid that has begun working its way into your system will be still at high concentration.

So I was very interested to read this paper about Hexafluorine.  Unlike water, hexafluorine is an active decontaminant – read, it tries to neutralize the acid rather than just dilute it down.  Specifically, it neutralizes the H+ ion and chelates the F- ion, rendering them harmless.  The paper discusses the use of the stuff on someone who had just received 70% HF vapour in the face.  Thanks to hexafluorine, he escaped unscathed, with none of the usual severe symptoms.

For a contrasting point of view, see this paper.  Rats exposed to HF had no difference in survival, regardless of whether water or hexafluorine was used.  Contra-contrast, this study, on human beings and animals, seems to support the use of it.

So if you are using HF, it may be a good idea to keep some of this stuff on time.