In 1934 first accepted "steam tables" were furnished when international community strongly felt the need of commonly accepted property table. International Association for the Properties of Water and Steam, or IAPWS released the first version of steam water properties formulation, IF67, in 1967. Subsequently IAWPS upgraded the version to IAPWS-95 in 1995 and IAPWS-IF97 in 1997 with major revisions in approach. The latest version provides consistent and accurate output up to a temperature range of 2000 Deg C and is suitable for speedy computer application.

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