珠海室内氡水平及分布特征

Indoor radon level and distribution characteristic in Zhuhai city

目的 通过对珠海市3个典型区域进行调查,探讨不同地质背景区域室内氡浓度的水平和分布.方法 按照地表岩性不同,分为珠海花岗岩、斗门花岗岩和斗门第四纪3个测区,使用活性炭盒累积法进行室内氡浓度测量.在部分测点同时使用活性炭盒累积法和固体径迹法进行室内氡浓度测量.结果 对80间房屋的活性碳盒累积法测量结果显示,珠海平均室内氡浓度为（66.0±49.8） Bq/m3,最大室内氡浓度为1078.5 Bq/m3.测区内23个测点短期活性炭盒累积法的测量结果为（69.5±37.7） Bq/m3,长期固体径迹法的测量结果为（88.8±49.1） Bq/m3.不同地表岩性区域室内氡浓度分别为：珠海花岗岩测区为（73.6±61.0）Bq/m3、斗门花岗岩测区为（87.5±58.3） Bq/m3、斗门第四纪测区为（48.6±22.6） Bq/m3.结论 地表岩性对区域室内氡浓度水平具有明显影响,珠海花岗岩和斗门花岗岩测区室内氡浓度明显高于斗门第四纪测区.建议结合地质背景研究区域室内氡浓度水平与分布特征.

Objective To analyze the indoor radon level and distribution characteristic in different geological background by studying the indoor radon level in three typical areas in Zhuhai City. Methods The region of investigation includes three districts： granite area in Zhuhai District, granite area in Doumen District and the Quaternary sedimentary area in Doumen District. Activated charcoal adsorption method was used to measure the indoor radon concentrations. In some sampling sites, solid state nuclear track detectors were used at the same time for the indoor radon measurement. Results The average indoor radon level included 80 buildings was （66. 0 ± 49.8） Bq/m3 using activated charcoal adsorption method and the maximum value was 1078.5 Bq/m3. The results of 23 sampling sites show that the average indoor radon level using solid state nuclear track detectors was （88.8 ± 49.1 ） Bq/m3 , and （69.5 ± 37.7） Bq/m3 by activated charcoal adsorption method. The indoor radon concentration was （73.6 ± 61.0）, （87.5 ± 58.3） and （48.6 ± 22.6） Bq/m3 in granite area in Zhuhai District, granite area in Doumen District and the Quaternary sedimentary area in Doumen District, respectively. Conclusions The surface lithology of an area has a certain impact on the indoor radon level. The indoor radon level in granite area in Zhuhai District and Doumen District is apparently higher than that in the Quaternary sedimentary area in Doumen District. The study of indoor radon level and distribution characteristic should be discussed in combination with geological background of area.