Relative Humidity (RH)

Relative Humidity (RH) is a measure of the amount of water vapour present in the air, expressed as a percentage of the maximum amount the air can hold at that temperature. At 100% RH, the air is fully saturated and condensation begins to form.

RH is temperature-dependent: warm air can hold more moisture than cold air. This means the same absolute amount of moisture will register as a lower RH percentage at higher temperatures. This relationship is critical for understanding dew point and condensation risk in cold storage environments.

Humidity directly affects product quality in pharmaceutical manufacturing, food processing, and electronics production. High humidity causes corrosion, mould growth, and degradation of hygroscopic materials. Low humidity causes static discharge and product desiccation. Monitoring and controlling RH is essential for product quality and safety.