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ANSI/AWWA C151/A21.51 was first international recognized drinking water ductile iron pipe standard since 1965. Since then, North America, European, and Asia regions developed their own standards for ductile iron pipes. Even these regional standards consist some similarity; however, unified ductile iron pipe standard is still unavailable up to now. The objective of this study is to investigate the difference between CNS and these international recognized standards for drinking water ductile iron pipes. The revised comments for the existing CNS standard are also provided. Dimensions, mechanical and hydraulic properties of CNS 10808, ISO 2531, BS EN545, ANSI/AWWA C151/21.51-02, and JIS G525 standards were investigated in the study. CNS and JIS are quite similar to each other. Each standard specifies its own pipe dimension and length based its needs. CNS, JIS, and AWWA standards provide detail dimensions for their joints and fittings. However, ISO, BS, and EN standards only require quality assurance test for each specified joint type. Asphalt exterior coating and cement mortar inner coating are required for all standards. T-type flexible joint is commonly accepted to be used in earthquake zone. The requirements for tensile strength and elongation at break, and hardness are similar for all standards. Pipe ductility should be evaluated by an impact test specified in AWWA standard. Graphite content exceeded 70% is only required by CNS standard. Static pressure test is required for each pipe for all standards.
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