... and conforming to the following International Standards:1) American standard (ASTM Sch 40 & Sch 80, SDR 21, ... ) British standard (BS 3505, BS 5255, 4515)3) Singaporean standard (SS 141, SS 272, SS 213)4) Australian standard (AS ... 1477, AS 1415)5) Japanese standard (JIS K 6742, JIS K ... JIS K 6743, JIS K 6739)6) National standard (GB 10002, GB 5836, GB 14823, GB ...