An extensive literature survey and evaluation has recently been completed under ASHRAE Research Project RP-1060 to extend the work of Hyland and Wexler and the range of the book Psychrometrics: Theory and Practice (ASHRAE 1996) and to quantify the interactions of moisture and air at higher temperatures, higher pressures, and higher moisture levels. This paper reports the results of this search with emphasis on experimentally obtained property values (or lack thereof) for the air-water vapor mixture and also provides a critical evaluation of the best available data for air and for water vapor to use in developing the properties of moist air.

Although the stated ranges of interest for ASHRAE RP-1060 are
Temperature: 200-320°C (400-600°F),
Pressure: Low corresponding to altitude of 2250 meters
(7500 feet) to high of 5 MPa, and
Humidity Ratio: 0 to 1 (max.),

the search for experimental data was universal, except that strictly low-temperature data were not specifically sought.

Units: Dual