Fundamental Constants
Vapor Pressure
Latet Heat
Saturated Densities

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Comparing Vapor Pressure

Comparisons of the saturated vapor pressure, from the triple point to the critical point is summarized below:

Relative Error	IAPWS-97	NBS/NRC-84	IFC-67
Maximum absolute error	0.018%	0.096%	0.135%
Average absolute error	0.004%	0.053%	0.060%
Root Mean Square error	0.007%	0.062%	0.070%

Note: The IAPWS-95 formulation is used as the baseline for comparisons.

A chart of the deviations is available in PDF format. Also, the Excel spreadsheet used to generate this summary and chart is also available:

Comparing vapor pressure (PDF file)

(10 KB; compare_vapor_pressure.pdf; January 21, 1999)

Comparing vapor pressure (Excel file)

(96 KB; compare_vapor_pressure.xls; January 21, 1999)