... can be made according and conforming to the following International Standards:1) American standard (ASTM Sch 40 & Sch 80, SDR 21, SDR ... 10002, GB 5836, GB 14823, GB 13664)7) International standard (ISO 4422, ISO 3633, IEC 614, GY 3050)Management: Wholly ... with a complete system of up-to-date testing equipment;International Projects: Water Supply Projects in Asia, Africa, New Zealand, Caribbean ...