Abstract
An experimental method for calibrating a chamber used for 85Kr monitoring is described. Experiments were made with a cylindrical ionization chamber, 114mm in diameter, 150mm in height with walls of stainless steel, by using 85Kr gaseous sources. In order to standardize a 85Kr gaseous source used for the experiments, the activity of 85Kr in the gas was determined by the method of mass spectrometry. The standardized gas was diluted with air to obtain the suitable concentration of 85Kr for the calibration.
In the calibration, the relation between activities of 85Kr in the chamber and saturated ionization currents was studied with the gases of various concentrations of 85Kr. The calibration factor of the chamber was found to be 5.42×10-9A/(μCi/cm3).