Making sense of relative humidity

Humidity and temperature are some of the essential environmental concerns in a cleanroom environment. Among them, relative humidity (RH) is one of the most challenging to measure for it requires analytical measurement. Choosing the right type and quality of sensors and properly ensuring them is a necessity. The bulk polymer resistive polymer provides a direct and secondary measurement of RH, protection against contaminants in the air and has relative immunity to surface contamination used for HVAC applications. On the other hand, the capacitive sensor is practical where a high degree of sensitivity is required at low RH and is ideal for high temperature environments. Calibrating sensors are usually done through hygrometers, which is the most precise method.