Concentrations of indoor and outdoor radon decay products in air and their doses to residents in Shanxi Province

The results of measurement of concentrations of 222Rn and its daughters indoors and outdoors carried out in 63 communities in Shanxi Province was presented. The concentrations of 222Rn and its daughters basically fit a log-normal distribution. The geometric means of the levels of 222Rn and its daughters indoors were 17.4 Bq·m-3 and 18.8 x 10-4 WL, and those outdoor were 7.0 Bq·m-3 and 13.4 x 10-4 WL, respectively. The indoor concentrations of 222Rn in basements and caved wellings were the highest, their geometric means being 61.6 Bq·m-3 and 30.7 Bq·m-3, respectively. Adopting the dose conversion factors and indoor occupancy factor proposed by UNSCEAR, the calculated annual effective dose equvalent was 1.58 mSv