ASME B16.33 pdf download MANUALLY OPERATED METALLIC GAS VALVES FOR USE IN GAS PIPING SYSTEMS UP TO 125 PSI 1 SCOPE 1.1 General This Standard covers requirements for manually oper- ated metallic valves sizes NPS 1 ⁄ 2 through NPS 2, for outdoor installation as gas shut-off valves at the end of the gas service line and before the gas...