Psychrometry chart

The above landscape screen is presented upon launching the application. The horizontal axis shows dry bulb temperature while the vertical axis the ‘humidity ratio’. There is a switch for choosing between the unit systems, metric or imperial.

The graph incorporates the following curves:

• Iso-relative humidity (red curves), some of which are annotated with the exact figure of relative humidity.
• Iso-enthalpy (cyan curves). The oblique grey scale gives enthalpy values for various curves.
• Iso-wet bulb temperature (blue curves)
• Comfort region (transparent green)

The reticle shown is translated by swiping within the bounds of the graph while the values of five parameters are read at each point:

• Dry bulb temperature
• Relative humidity
• Wet bulb temperature
• Specific enthalpy
• Dew point

Finally the comfort region is depicted in green.