Evaluation of the Influence of Thoron on Portable Radon Measurement Devices

Radiation exposure due to 222Rn is recognized as a matter of international concern for its health risk to humans. Portable devices for 222Rn concentration measurements, which are user-friendly, can be easily installed and provides a direct readout of values of 222Rn concentration on the built-in LCD (liquid-crystal display) and internal storage. However, there is a possibility that 220Rn can influence experiments for 222Rn measurement because of some similarity in their element properties. In this preliminary study, the influence of 220Rn on the performance of two commercial portable devices for 222Rn measurements was investigated. It was found that the indicated value for radon concentration in these devices could be affected by the presence of thoron gas.