About ten years ago I wanted to make one of these air tanks out of a
> freon jug. I bought a kit with a valve, hose and safety valve in it . My
> dad had worked on air conditioners for 20some years, so I went and asked
> him for an empty tank. He told me that about ten years before he was
> asked by the company he worked for(a large chemical company that also
> made freon) to try to find them some old freon tanks so they could test
> them. He rounded up several and he was told to take them to the
> company's safety research lab. He took them to the lab and while he was
> there he asked why they wanted them. The man over the lab told him that a
> person had made an air tank from one of their old freon jugs and went to
> a gas station to fill the tank. He was holding the tank between his legs
> when it split apart. He lived but without some of his vital parts, anyway
> he decided to file a lawsuit against this company because the tank blew
> up. I cant tell you to use your tank because there are thousands out
> there that are ok, But I went out and bought a new portable air tank.
> Jim Hubbard
I have a 50 lb R-22 tank that I've been using as my portable air tank for OVER 30 YEARS!! It's always been kept in the house which may have helped. I suppose though, I should go looking for a fresh one. T'care, Mike