PVC Pipe. The use of PVC pipe is common but NOT RECOMMENDED for use with Galvanized Pipe. Galvanized piping is commonly used for water distribution and for Black Pipe. Black pipe is the most commonly used pipe RECOMMENDED for Copper Pipe. Copper pipe is commonly RECOMMENDED for clean air, it works very Stainless Steel. The RECOMMENDED use of stainless steel to minimize corrosion has Aluminum Pipe. The latest technology are push-to-connect aluminum piping systems