This standard provides the minimum requirements for the materials, design, manufacture, testing, and inspection of dual-disc swing-check valves, suitable for waterworks service, 2-in. through 48-in. (50-mm through 1,200-mm) NPS, including materials and testing NPS for clean water having a pH range from 6 to 10 and a temperature range of 33°-125°F (0.6°-52°C). Major changes in this revision include a requirement for NSF/ANSI certification and information about valves weighing more than 60 lb (27.2 kg).