CONTINUOUS MEASUREMENTS OF OUTDOOR RADON CONCENTRATIONS AT VARIOUS LOCATIONS IN EAST ASIA

摘要

Four electrostatic radon monitors were constructed to continuously measure outdoor ~(222)Rn concentrations at various locations. Outdoor ~(222)Rn concentrations were measured at six locations in Japan and China. The annual mean ~(222)Rn concentrations at Nagoya, Kasugai, Toki, and Kanazawa in Japan were 5.1, 6.0, 6.1, and 5.8 Bq m~(-3), respectively. The ~(222)Rn concentrations at Nagoya, Kasugai, and Toki showed a diurnal variation clearly in autumn and a seasonal pattern of a spring-summer minimum and an autumn-winter maximum. The ~(222)Rn concentrations at Kanazawa showed a diurnal variation clearly in summer. At Beijing and Fuzhou in China, the annual mean concentration levels were 7.0 and 11.4 Bq m~(-3) and the pattern of the diurnal variations was different from that at Nagoya. The seasonal variations of a summer minimum and a winter maximum were almost similar at Beijing and Fuzhou.