地热田高氡建筑治理与效果评价

目的 探讨地热田高氡房屋氡的来源与治理。方法 α径迹探测器（ATD）分冬夏两个季节测量室内和土壤中的氡浓度。采用γ能谱法测量房屋主体建材放射性核素含量；采用6150 A D/6H X-γ剂量率仪测量房屋主体建材的外照射剂量率；对其中一栋房屋实施土壤减压技术的降氡改造。结果 夏冬季32个房间氡浓度均值分别为（106.4 ±63.7） Bq/m³和（421.3 ±138.2） Bq/m³，分别有12.5%和96.9%的房间超过150 Bq/m³。建筑物周围土壤氡浓度均值为12890 Bq/m³（检测点n = 24），是北京市土壤氡浓度典型值（7600 Bq/m³）的1.7倍。实施土壤减压改造后冬夏季房屋中氡浓度均可降至 < 100 Bq/m³，主动减压法降氡率为94.6%，被动减压法降氡率为71.4%。结论 土壤减压法对降低底层房间氡浓度效果明显，地热田居住环境中氡的问题应引起关注。

Building management and effect evaluation of high radon in geothermal field

Objective To explore the source and control of radon in high radon houses in geothermal fields; Methods Radon concentration in indoor and soil was measured by ATD detector in winter and summer; radionuclides in building materials were measured by gamma-ray spectrometry; radionuclides dose rates of building materials were measured by 6150 A D/ 6H X-γ ray detector; and radon reduction technology was applied to one of the houses;Results The average radon concentrations in 32 rooms were （106.4 ±63.7） Bq/m³ (summer) and （421.3 ±138.2） Bq/m³ (winter), and the concentrations in 12.5% (summer) and 96.9% (winter) of the rooms exceed 150 Bq/m³. The average radon concentration in soil around buildings was 12890 Bq/m³ (n = 24), which is 1.7 times of the typical soil radon concentration in Beijing (7600 Bq/m³). After soil decompression, the radon concentration in the house could be reduced to less than 100 Bq/m³. The radon reduction rates of active decompression and passive decompression were 94.6% and 71.4%, respectively.Conclusion The effect of soil decompression on reducing radon concentration in the bottom rooms is obvious. Attention should be paid to the radon in residential environment of geothermal field.