MSS - Manufacturers Standardization Society of the Valve and Fittings Industry.
Scope
This Standard Practice covers Metallic Gas Distribution Valves designed for operation at any pressure from 0 psig to a maximum of 285 psig@ at operating temperatures ranging from -20 ??to 150 ?? and sizes from NPS 1/2 to NPS 12. PURPOSE To provide a Standard Practice for metallic valves used in fuel gas piping systems which are manually operated both above and below ground.