Fluorine removal from fume

Fluorocarbon greases (Krytox) originally required a chlorinated fluorocarbon for removal. In the last few years, it was found that an industrial solvent (such as BH-38 from Spartan Chemical Co. ) can remove Krytox. Tests that this author has conducted seem to show a film of some kind remains on the joint, so it is unknown exactly how safe it is to heat a joint or stopcock that has been cleaned with this technique. Do not use heat to remove Krytox because heating (> 260°C) will produce fumes (lethal fluorine compounds, such as HF) that are highly toxic. For more information on cleaning these greases, see Sec. 3.3.3. 

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