Abstract
An irradiation radon chamber with a total volume of 87l was designed and constructed. This system is based on a natural radon source and a traceable reference radon detector (AB-5 Radon monitor), which allows the radon concentrations inside the chamber to be obtained in different ranges. The radon chamber was used to determine both the calibration factor of the radon detector and the equilibrium factor between radon and its short-lived daughters. In addition, the dependence of the equilibrium factor on the temperature and flow rate was studied. The equilibrium factor was observed to be linearly dependent on the flow rate and its value at 20°C was found to be 2.2 times higher than the equilibrium factor value at 50°C. These values are in good agreement with those reported using the surface barrier detector method.