Psychrometric Help Page

Psychrometrics are the measurements of moist air, from the roots psychro and metric. It is not the same as psychometric, which your spell checker may offer you as an alternative!

Some Moist Air Properties

dry bulb temperature (^oF or ^oC)

wet bulb temperature (^oF or ^oC)

dew point temperature (^oF or ^oC)

relative humidity (%)

humidity ratio (lb H₂0/lb dry air, or kg H₂0/kg dry air)

enthalpy (BTU/lb dry air, or kJ/kg dry air)

density (lb/ft³, or kg/m³)

Other factoids and references

We use psychrometric properties for environment control. A lot of energy can be used in conditioning air, and with an understanding of psychrometrics, heat transfer and thermodynamics, one can estimate energy flows. Psychrometric Charts are a useful tool for visualizing moist air relations.

Two Professional Engineering Societies set standards and handbooks that define and provide instruction and use guidelines for psychrometric properties.

Here are hot links to the societies:

The Society for Engineering in Agriculture, Food, and Biological Systems.

American Society of Heating, Refrigeration, and Heating Engineers.