ASME Steam Table, known as IFC-67, is the most widely used to estimated water or steam physical properties. However, it has been officially replaced by a new formulation known as IAPWS-IF97.

Actually, the most accurate formulation is IAPWS-95, which stands for "IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use". IAPWS-IF97 is designed to meet special industrial needs: fast computation and no frequent change [1]. IAPWS-IF97 is now "the international standard for calculations in the steam power industry" [2].