1. Radiant Temperature: The difference of the radiant temperature in all directions remain less than 9F
  2. Air Temperature: The room temperature stratification is less than 3.5F between head and feet of a sitting person.
  3. Air Speed and Turbulences: For speeds under 0.08 m/s, less than 6% of people will feel a draft.
  4. Humidity: Humidity levels depend on the seasons, but generally the relative humidity should be about 40% – 60%.