NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
The NIST REFPROP database for highly accurate properties of industrially important fluids
Published
Author(s)
Marcia L. Huber, Eric W. Lemmon, Ian Bell, Mark O. McLinden
Abstract
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.
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], https://doi.org/10.1021/acs.iecr.2c01427, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=934606
(Accessed October 9, 2025)