我国非铀矿山^222Rn、^220Rn浓度季节变化研究  

Seasonal variation in concentration of radon and thoron at non-uranium mines in China

作　　者：崔宏星[1] 武云云[1] 张庆召[1] 尚兵[1] 

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所,北京100088

出　　处：《中华放射医学与防护杂志》2009年第6期639-642,共4页Chinese Journal of Radiological Medicine and Protection

基　　金：科技部科研院所社会公益研究专项资助项目（2005DIBIJ087）

摘　　要：目的研究非铀矿山中^222Rn、^220Rn浓度的季节变化规律。方法选取云南、山东、新疆、黑龙江、湖南和贵州6个省份的铜、金、铝、锰、锑、钨、铜镍和煤矿共8类9个矿山，采用LD-P型^222Rn-^220Rn分辨探测器对井下不同季节^222Rn和^220Rn浓度进行了测量。结果井下^222Rn浓度存在明显的季节变化，夏季^222Rn浓度为35．5～4841Bq／m^2，其中4个矿^222Rn浓度均值超过1000Bq／m^3。冬季^222Rn浓度均值为5～1917Bq／m^3，只有1个矿超过1000Bq／m^3。夏季与冬季的比值在2～12之间。各矿间^222Rn浓度差异很大，通风是影响其变化的重要因素。^220Rn浓度的季节变化略呈夏高冬低的趋势，由于受到布放位置的影响，其规律性有待进一步确认。结论井下^222Rn、^220Rn浓度随季节而变化，在估算矿工受照剂量时应考虑季节变化的影响；在矿山氡测量中应避免采用瞬时测量方法；采用累积测量方法时，也应考虑季节变化的影响，合理的暴露时间应为半年，同时要注意季节的选择；对于季度性（3个月）的测量结果应该进行季节修正。Objective To study the seasonal variation in concentrations of radon and thoron in nonuranium mine. Methods Eight kinds of mineral types from 9 non-uranium mines were selected, including copper, gold, aluminium, manganese, antimonium, tungsten,copper-nickel and coal mines in 6 provinces, such as Yunnan, Shandong, Xinjiang, Heilongjiang, Hunan and Guizhou. LD-P R-T discriminative detectors were used to measure radon and thoron concentrations in underground mines during four seasons in one year. Results Radon concentrations in underground mines showed a significantly seasonal variation. Radon concentration ranged from 35.5 to 4841 Bq/m^3 in summer, and the average value in four mines exceeded 1000 Bq/m^3 of the control limit for workplace （GB 18871-2002） . In winter, radon concentration ranged from 5 to 1917 Bq/m^3 , only one of them exceeded the control limit. The ratio of radon from summer to winter ranged from 2 to 12. Ventilation was one of the main factors which influenced the seasonal variation of radon. While the thoron concentration in underground mines showed a tendency that it was higher in summer and lower in winter. It was difficult to attain representative values for thoron, due to the influence of location of detectors. The seasonal variation of thoron should he further studied. Conclusions Seasonal varation for radon and thoron should be taken into account to estimate the effective dose to miners. The values of radon concentration during the short term should be corrected.

关 键 词：非铀矿山 ^222RN ^220RN 季节变化 

分 类 号：P619.1[天文地球—矿床学]