ASME has been defining piping safety since 1922. ASME B31.9 contains rules for the piping in industrial, institutional, commercial, and public buildings, and multi-unit residences, which does not require the range of sizes, pressures, and temperatures covered in B31.1. ASME B31.9 prescribes requirements for the design, materials, fabrication, installation, inspection, examination, and testing of piping systems for building services. It includes piping systems in the building or within the property limits. It joins with ASME's many other safety standards governing the building and construction industry, including the A17 series on elevators and escalators; the B30 series on cranes, hoists and lifts; and the A112 series on plumbing. B31.9 also serves as a companion to ASME?s other B31 codes on piping systems. Together, they remain essential references for anyone engaged with piping. Key changes to this revision include the addition of allowable stresses for (austenitic) stainless steels to TableI-1, and revisions to references in Mandatory Appendix III. Careful application of these B31 codes will help users to comply with applicable regulations within their jurisdictions, while achieving the operational, cost and safety benefits to be gained from the many industry best-practices detailed within these volumes. Intended for designers, owners, regulators, inspectors, and manufacturers of industrial, institutional, commercial, and public building pipelines.