This paper presents a process in which a radon monitor based on the electrostatic collection method is used to measure the (222)Rn and (220)Rn exhalation rates simultaneously and continuously employing a ventilation-type accumulation chamber. Generally, the radon exhalation rate can be measured by accumulation technique, but cannot be measured continuously. The advantage of this method using a ventilation-type accumulation chamber is that the radon exhalation rates can be measured continuously. Even though the environmental air is drawn into the chamber, the low atmospheric values of radon and thoron do not influence the measurement accuracy. The (222)Rn and (220)Rn exhalation rates error from the environmental air is less than 5% in this experiment.
Keywords: 220Rn; 222Rn; RAD7; exhalation rate; isotope measurements; radioactive nuclides.