南宁市地铁1号线地铁站内氡活度浓度调查

本研究采用以CR-39为探测元件的被动式累积测氡杯对广西省南宁市地铁1号线25个地铁站进行了为期一年的氡活度浓度累积测量。为确保测量结果准确性,采用CR-39暴露本底代替裸片本底,并在操作上将提供暴露本底的本底测氡杯始终置于密闭真空状态,进行了严格的质量控制。测量结果显示,25个地铁站全年平均氡活度浓度为(13.9±3.7)Bq/m³;分布范围是(6.4～32.9)Bq/m³。冬季平均氡活度浓度(18.1±2.2 Bq/m³)明显高于春(12.7±1.9 Bq/m³)、夏(12.9±3.5 Bq/m³)、秋(12.4±4.4 Bq/m³)三季;没有观察到地下一层和地下二层氡活度浓度水平有统计学意义的显著差异;没有观察到各地铁站之间氡活度浓度有统计学意义的显著差异。

Survey on radon activity concentration of underground metro station in Nanning city

Subway has become one of the most important traffic tools for the public in nearly all the provincial capital cities in China. To confirm the radiation safety in this special underground spaces, a one-year survey of radon activity concentration measurement was carried out in all metro stations at Line-one. Totally 25 stations were involved. Passive integrated radon cup monitor with CR-39 as a detector was adopted for radon integrated measurement. For measurement quality control, the background track density of CR-39 was strictly defined and controlled during operation of the survey. The annual average radon activity concentration of all the 25 stations is (13.9±3.7) Bq/m³ range from 6.4 to 32.9 Bq/m³. For seasonal variation, radon activity concentration in winter was obviously higher than the other three seasons. It was (18.1±2.2) Bq/m³. For Spring, Summer and Autumn, they were (12.7±1.9), (12.9±3.5) and (12.4±4.4) Bq/m³ respectively. Comparisons of different stations and different floors were also performed and no statistically significant difference was observed.