Relative Humidity

Relative humidity (RH) is the amount of moisture in a given sample of air at a given temperature in relation to the maximum amount of moisture that the sample could contain at the same temperature. If the air is holding all the moisture it can for a specific set of conditions, it is said to be saturated (100 percent RH). Since air is a gas, it expands as it is heated, and as it gets warmer the amount of moisture it can hold increases, causing its relative humidity to decrease. Therefore, in a system using subfloor air distribution, the ambient relative humidity will always be lower than in the subfloor.

Ambient levels between 45 and 50 percent RH are optimal for system reliability. Most data processing equipment can operate ...

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