Psychrometric Data Calculator in SI Units
This Demonstration computes psychrometric data in SI units. In order to read all the thermal variables from a psychrometric chart, first fix the value of the dry-bulb temperature and one of these additional variables: the wet-bulb temperature, the dew point temperature, the relative humidity or the moisture content. Then use the slider to set the value of the selected variable.
 R. M. Felder and R. W. Rousseau, Elementary Principles of Chemical Processes, 3rd ed., New York: John Wiley & Sons, 2004.