室内~(222)Rn/~(220)Rn子体平衡因子的初步测量

为了测量222Rn/220Rn子体水平及其与222Rn/220Rn浓度之间的平衡关系,采用连续测氡仪和氡钍子体连续监测仪,选择包头地区几种典型居室和工作场所,对其空气中222Rn/220Rn及其子体浓度进行测量。结果显示,工作场所和居室中222Rn平衡因子均值分别为0.35和0.43,工作场所和居室距墙壁20cm处220Rn平衡因子均为0.030;室内220Rn平衡当量浓度昼夜变化与222Rn类似,即白天低、晚上高;222Rn/220Rn浓度瞬时测量值与累积结果存在较大差异,平均比例分别为2.1和1.7。

Primary Measure of Equipment Factor of 222Rn/220Rn Indoor

The activity concentration of ²²²Rn, ²²⁰Rn and their progenies of certain working places and dwellings in Baotou city were measured simultaneously. Based on these results, the equipment factor of ²²²Rn is 0.35 for working places and 0.43 for dwellings, while equipment factor of ²²⁰Rn measured at 20 cm distance from wall is 0.030 for both working places and dwellings. Preliminary results show that the temporal change of ²²⁰Rn equilibrium equivalent concentration is same as ²²²Rn which is high in midnight and low in afternoon, and significant difference between instant and accumulated measure result of ²²²Rn, ²²⁰Rn activity concentration is found, with the factor of 2.1 and 1.7.