ASME B16.40 pdf download Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution Systems 2 CONSTRUCTION 2.1 General (a) The workmanship used in the manufacture and assemblyofeachvalveshallprovide gas tightness, safety and reliability of performance, and freedom from injuri- ous imperfections and defects. (b) Design details not addressed in this Standard are the responsibility of the manufacturer. 2.2 Materials 2.2.1...