Take a look at 501.10(A) in the 2008 code. Note, you can never use galvanized SCH40 pipe for electrical work. You would have to use rigid galvanized steel conduit.
Take a look at 501.10(A) in the 2008 code. Note, you can never use galvanized SCH40 pipe for electrical work. You would have to use rigid galvanized steel conduit.