摘要
目的某厂历史遗留废物中的放射性水平较高,退役操作人员可能受到较大的受照剂量。开展伴生放射性废物回取整备的辐射安全分析,提出适当的辐射防护措施,尽可能降低操作人员的受照剂量。方法分析该厂暂存库内的伴生放射性废物源项,采用点核积分软件MicroShield进行建模计算,并结合现场监测数据,提出退役工况下的辐射防护措施。结果计算得出的暂存库内废物堆体附近最大γ辐射剂量率为313.9μGy/h,与监测水平相当;采取距离衰减和适当的屏蔽措施对降低操作岗位的γ辐射剂量率效果显著。结论暂存库退役现场对操作人员危害较大,采取密闭隔离、远距离操作和个人防护等措施后,可以有效降低操作人员受照剂量。
Objective The radioactivity level in historical waste from a plant is high,and decommissioning operators may be exposed to high radiation doses.The objective of the study is to carry out a radiation safety analysis of the retrieval and conditioning of naturally occurring radioactive material(NORM)waste,put forward appropriate radiation protection measures,and minimize the exposure doses of operators.Methods The source terms of NORM waste in the temporary storehouse were analyzed;MicroShield,a point kernel integration program,was used for modeling and calculation;and radiation protection measures under decommissioning conditions were put forward based on on-site monitoring data.Results The maximum gamma dose rate calculated near the waste pile in the temporary storehouse was 313.9μGy/h,equivalent to the monitoring level;distance decay and appropriate shielding measures significantly reduced gamma dose rates for operators.Conclusion Decommissioning sites of temporary storehouses are of great harm to operators.Measures such as shielding,isolation,remote operations,and personal protection can effectively reduce the exposure doses of operators.
作者
谢占军
詹乐音
张贺飞
XIE Zhanjun;ZHAN Yueyin;ZHANG Hefei(The Fourth Research and Design Engineering Corporation of CNNC,Shijiazhuang 050021 China)
出处
《中国辐射卫生》
2023年第5期527-531,共5页
Chinese Journal of Radiological Health
关键词
钍系
辐射防护
点核积分法
外照射
Thorium series
Radiation protection
Point kernel integration method
External irradiation
