Bird
Rest in Peace
Bill, most propane companies used copper lines and may be going to some form of plastic now. I used to do gas leakage surveys for natural gas companies and the pipe used has changed over the years. I think all the old wooden pipe (Bois 'd Arc) is gone now, but I found cast iron pipe, black pipe, galvanized pipe, coated pipe, copper (which ain't recommended for natural gas anymore), etc. And now they're all going to the yellow "plastic" pipe. With the metal pipes, you could connect a sending unit and trace exactly where the pipe was. Now with the plastic pipe, that doesn't work, so I think all the gas companies are learning to wrap it with a "trace" wire so you can find it later.
Bird
Bird