医用重离子加速器辐射水平分析及监测评价

Analysis and Monitoring Evaluation of Radiation from Medical Heavy Ion Accelerator

为掌握我国自主研发的医用重离子加速器辐射水平,通过模拟计算给出瞬时辐射、气态流出物感生放射性源强,结合加速器大厅及治疗室辐射屏蔽设计,计算贯穿辐射及空气浸没外照射途径对工作人员和公众辐射所致剂量。根据医用重离子加速器运行后实际工况进行辐射环境监测,对所致工作人员和公众辐射剂量进行计算,工作人员最大年辐射剂量约为3.94×10^(-2)mSv,公众人员最大年辐射剂量约为8.53×10^(-7)mSv,模拟计算与实测结果相互印证,模型可用于辐射屏蔽设计的数据支撑。对加速器运行以来工作人员个人年累积剂量资料进行复核,工作人员及公众辐射剂量均满足剂量限值要求。

In order to grasp the radiation level of medical heavy ion accelerators independently developed in China,the instantaneous radiation and the intensity of radioactive sources induced by gaseous effluents were calculated through simulation.Combined with the radiation shielding design of the accelerator placement room and treatment room,the dose of penetrating radiation and air immersion external exposure to the staff and the public was calculated.Based on the actual operating conditions of medical heavy ion accelerators,radiation environment monitoring was carried out to calculate the radiation dose for the staff and the public.The maximum annual radiation dose for the staff was approximately 3.94×10^(-2) mSv,while that for the public was approximately 8.53×10^(-7) mSv,the simulated and measured results confirmed each other.The model could be used for data support in radiation shielding design.The annual cumulative dose of the staff since the operation of the accelerators was reviewed,and the radiation doses of both staff and the public met the dose limit requirements.