某工业探伤9 MeV电子加速器探伤室的辐射安全防护效果评价

Radiation safety effect evaluation of a 9 MeV electron accelerator for industrial flaw detection

目的 了解某新建9 MeV电子加速器探伤室的辐射防护效果。方法 采用美国国家辐射防护和测量局(National Council on Radiation Protection and Measurements,NCRP)的NCPR-51和NCPR-151报告中推荐的辐射屏蔽理论计算方法计算出探伤室屏蔽墙体的理论厚度和关注点剂量率,并与2021年实际检测结果进行比较。结果 某9 MeV电子直线加速器探伤室在运行期间,依据混凝土屏蔽墙设计值计算出墙体四周外30 cm处人员可达位置的剂量率在0.03~0.64μSv/h之间,屋顶外30 cm处的剂量率为10μSv/h。结论 结合屏蔽计算结果和实际现场监测测量结果,表明某新建9 MeV工业探伤电子加速器探伤室的辐射屏蔽设计、辐射安全防护装置和辐射防护管理措施符合我国工业探伤室的辐射防护标准规定。

Objective To master the radiation protection effect of the flaw detection room of a newly-built 9 MeV electron accelerator.Methods The theoretical calculation method of radiation shielding recommended in the NCRP-51 and NCRP-151 reports of the National Council on Radiation Protection and Measurements(NCRP)was used to calculate the theoretical thickness of the shielding wall and the dose rate at the point of concern in the flaw detection room and compared with the actual test results in 2021.Results During the operation of 9 MeV electron linear accelerator flaw detection room,according to the design value of concrete shielding wall,the dose rate at the accessible position 30 cm outside the wall is calculated to be 0.03-0.64μSv/h,the dose rate at 30 cm outside the roof is 10μSv/h.Conclusion Combined with the shielding calculation results and the actual field monitoring and measurement results,it shows that the radiation shielding design,radiation safety protection devices and radiation protection management measures of the newly-built 9 MeV industrial flaw detection electron accelerator flaw detection room conform to the radiation protection standards of industrial flaw detection room in China.