Technical Note
Details
Humidity Definition
Humidity is the amount of water vapor in a gas, most commonly air. Relative humidity (RH%) expresses the ratio between actual water vapor pressure and saturated water vapor pressure at the same condition. Humidity is harder to measure accurately than temperature because it is affected by air pressure, temperature and calibration conditions.
Measurement Methods
Humidity can be measured by many principles, including wet-and-dry bulb methods, dew point methods and electronic humidity sensors. Each method has its own range, accuracy, response time and maintenance requirements.
Selecting a Measurement Method
A suitable humidity solution depends on the environment, required accuracy, contamination risk, temperature range, response speed and maintenance conditions. Industrial applications often choose a practical balance between reliability and precision.
Sensor Precautions
Humidity sensors should be protected from condensation, corrosive gas, dust and mechanical damage. Installation position, air circulation and regular calibration all affect the reliability of long-term humidity control.