WAC 296-806-43024. Follow these requirements for pressure pipes

You must provide steam or air pressure piping on power-driven hammers that meets or exceeds the requirements in: (1) ANSI B31.1.0-1967, Power Piping, with addenda ANSI B31.1.06-1971, for hammers constructed before January 1, 2005. (2) ANSI B31.1.0-2001, Power Piping, with addenda ANSI B31.1.0A-2001, for hammers constructed on or after January 1, 2005.