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Determining Relative Humidity

Relative humidity represents the extent to which air is saturated with water at a given temperature. Relative humidity, especially in the winter is important when raising plants.

The air is too dry if you get a shock from a spark every time you touch something.

The air is too moist if water is condensing on the windows,.

Another way to get a value for the relative humidity is to use a wet-and-dry bulb thermometer. First measure the air temperature. Next wrap a small piece of tissue around the bulb and wet it. Wait about ten minutes until the temperature stabilizes - it will be lower due to evaporation. Subtract the wet temperature from the dry temperature and look up the humidity in the table below.

This table is not yet done. Links to other sites and user contributions welcome

Prepared by Trevor Croll,

42 Pearse Street, Keperra, Queensland Australia, 4054.
Phone 61 7 3855 1115