[PaulProe]

When PVC fails (and it will under air pressure) it is a catastrophic failure. Little shards everywhere. The stuff is bad news. Guys will say they've never had a problem, but it is just a matter of time.

Look into the aluminum tube type systems that are popular now. The tube is coated with blue epoxy, makes it real pretty.

Next choice would be sweated copper lines.

Last choice is black iron pipe. You'll never get it to seal 100% so it is problematic.

There is also a system available that uses nylon tubing to connect from fitting to fitting, but I don't have any experience with it.

Paul