Effect of temperature and humidity on the performance of Charcoal CanisterPassive Rn detectors

Abstract

The dependence of radon adsorption on the temperature up to 35 °C was studied for 4" open face (OF) charcoal canister at different values of relative humidity using a radon calibration chamber with variable and controlled radon concentration, humidity, and temperature which was previously constructed. Sets of calibration factor (CF) and adjusting factor (AF) curves were established at 20, 25, 30, and 35 °C and,different humidity (RH%). These curves are used to extend the use of open-faced charcoal canisters for higher temperature and humidity applications. The optimum exposure time to achieve the best detection accuracy was estimated between 2 and 4 days depending on relative humidity. The open-faced canisters havehigher efficiency of radon absorption at low temperature.