i just posted a reply to another thread but here goes.if you must cut a propane (or other flammable) tank,you can purge said vessel w/ argon or nitrogen-any tungsten inert gas. thats what we do when welding stainlesspipe(so it doesn't "sugar" i.e. slag in the pipe), also when filling towers w/ catalyst in refineries as some catalysts react w/ oxygen.you may have to hire a welder to do this or you can get the tanks @ any welding supply shop or air liquide(name of the company) rental.
