Review of indoor radon studies with a focus on continuous time-resolved measurement

Sakoda, Akihiro   ; Hasan, Md. M.*; Kanzaki, Norie   ; Iimoto, Takeshi*

Radon is a naturally occurring radioactive gas that can cause lung cancer. Many nationwide and regional surveys, including Japan, on radon concentration in the indoor air of dwellings were implemented in the past couple of decades and compiled by international reports; the annual radon concentration in each nation or region was determined by long-term integrating measurement for dose assessment of the public. On the other hand, efforts of continuous time-resolved monitoring of radon, in addition to relevant environmental factors, have also been made for research purposes to elucidate physical mechanisms of spatial and time variations and elevation of indoor radon concentration as well as to investigate the possibility of predicting annual averages from short- or mid-term measurements. The aims of the present work are to update findings from such measurements and explore what should be future work.