New Test Method for Measuring Absolute Humidity with Thermal Hygrometers
1. Scope
This test method will describe the continuous measurement of absolute humidity and water vapor concentration using thermal conductivity or thermal mass-based sensors. It will outline the operating principles, calibration requirements, gas flow conditioning, and temperature compensation procedures necessary for accurate measurement. It is particularly applicable to measurements in harsh, high-temperature, or corrosive atmospheric environments.
Thermal humidity sensors offer robust alternatives in environments where capacitive or condensation-based sensors cannot operate reliably (e.g., highly contaminated industrial meteorology sites, extreme temperatures). A standardized method is needed to define calibration against dry reference gases, flow control, and performance criteria to ensure data accuracy. Users include industrial meteorologists, environmental compliance monitors, and researchers studying harsh atmospheric boundary layers.