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The NIST REFPROP database for highly accurate properties of industrially important fluids



Marcia L. Huber, Eric W. Lemmon, Ian Bell, Mark O. McLinden


The NIST REFPROP database is a powerful tool for calculating thermophysical properties of industrially important fluids, and this manuscript describes the models implemented in, and features of, this database. REFPROP implements the most accurate models available for selected pure fluids and their mixtures that are valid over the entire fluid range including gas, liquid, and supercritical states, with the goal of uncertainties approaching the level of the underlying experimental data. The equations of state for thermodynamic properties are primarily of the Helmholtz energy form; a variety of models are implemented for the transport properties. We document the models for the 147 fluids included in the current version. A graphical user interface generates tables and provides extensive plotting capabilities. Properties can also be accessed through third-party apps or user-written code via the core property subroutines compiled into a shared library. REFPROP disseminates international standards in both the natural gas and refrigeration industries, as well as standards for water/steam.
Industrial and Engineering Chemistry Research


Equations of state, REFPROP, surface tension, thermal conductivity, thermodynamic properties, viscosity


Huber, M. , Lemmon, E. , Bell, I. and McLinden, M. (2022), The NIST REFPROP database for highly accurate properties of industrially important fluids, Industrial and Engineering Chemistry Research, [online],, (Accessed June 14, 2024)


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Created June 21, 2022, Updated November 29, 2022