This Standard covers manually operated thermoplasticvalves in nominal valve sizes 1/2 through 12. Thesevalves are intended for use below ground in thermoplasticfuel gas distribution mains and service lines. Themaximum operating pressure (MOP) at which such distributionpiping systems may be operated is in accordancewith the Code of Federal Regulations (CFR)Title 49, Part 192, Transportation of Natural and OtherGas by Pipeline; Minimum Safety Standards, for temperatureranges of -20F to 140F (-29C to 60C).