Before beginning any welding, the welding surfaces must be clean and free of any material that may be detrimental to the weld, and the pipe or component must be aligned to provide the most favorable condition for depositing the root bead. This alignment must be preserved while the root bead is being deposited.
Compiled from the Electronic Code of Federal Regulations (eCFR), an editorial compilation and not an official legal edition of the CFR. The official text is the Federal Register and the annual CFR edition. §192.235 on eCFR.