two main things you need for a fire are solvent vapor and heat
eliminate these two things and your safe
evaporation is very dangerous to the liver so dont do it
as far as heat goes if you cant put your bare hand on it its dangerous
try a freeze to avoid all evaporation
and the heat - hot water bath is the best you can do - heating solvents beyond 140F(hot tap water) is asking for trouble
as a side note i can pull 1.1% - 1.6% every time and never have to use more than hot tap water and a freezer
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