后装放射治疗场所屏蔽改造方案的设计与分析  

Design and analysis on shielding reconstruction project of brachytherapy room

作　　者：郝龙英[1] 马永忠[2] 

机构地区：[1]北京大学首钢医院肿瘤科,100144 [2]北京市疾病预防控制中心/北京市预防医学研究中心

出　　处：《职业与健康》2015年第15期2030-2033,共4页Occupation and Health

基　　金：北京市预防医学公益应用研究项目(项目编号:2014-BJYJ-07)

摘　　要：目的根据不同类型后装放射治疗设备的放射防护要求,确定后装治疗机房合理的的屏蔽改造方案,为后装放射治疗的放射防护提供指导。方法以北京某医院2014年拟改造的192Ir后装治疗机房及其拟更新的60Co后装治疗机为研究对象,对照剂量率控制目标值,依据GBZ/T 201.1-2007、GBZ/T 201.3-2014、GBZ 121-2002和IAEA No.47等国内外技术标准核算并确定场所的屏蔽改造方案。结果针对原370 GBq192Ir后装治疗机房,估算出改造成74 GBq60Co后装治疗机房外围的辐射剂量率,据此初步确定了该后装治疗机房的屏蔽防护改造方案:1将机房北墙、东墙、南墙和室顶砼屏蔽厚度分别增加30、20、15和30 cm;2将迷路内墙增加1个半值层厚度(HVL)砼屏蔽或将机房入口防护门更新为6 mm Pb的防护门。结论结合60Co后装治疗源的辐射特性参数,在原有192Ir后装治疗机房的基础上进行局部屏蔽改造是合理可行的。[Objective]To determine the reasonable shielding reconstruction project of brachytherapy room according to the radiation protection requirements of different brachytherapy equipments, provide guidance for radiation protection of brachutherapy.[nethods]A 192Ir brachytherapy room to be reconstructed and a 60^Co brachytherapy equipment to be installed in a hospital in Beijing in 2014 were selected as the research objects, and the shielding reconstruction project of room was estimated and confirmed according to the control goal of dose rate and the relative national and international technology criterions including GBZ/T 201.1-2007, GBZ/T 201.3-2014, GBZ 121-2002 and IAEA No.47.[Results]The radiation dose rate outside the 74GBq 60^Co brachytherapy room to be reconstructed from a 370 GBq 192^Ir brachytherapy room were calculated, and the shielding reconstruction project of brachytherapy room was drawn as follows： （1）concrete shielding with thickness of 30 cm, 20 cm, 15 cm and 30 cm should be added to north, east, south and ceiling wall of the room respectively; （2）concrete shielding with thickness of one HVL should be added to internal maze wall of the room or the protective door should be replaced with another one with the lead thickness of 6 mm. [Conclusion]Combining with the radiation parameters of 60^Co brachytherapy radioactive source, local shielding reconstruction on the basis of original 192^Ir brachytherapy room is reasonable and feasible.

关 键 词：后装治疗机 后装放射治疗场所 屏蔽改造 放射防护 

分 类 号：R181.3[医药卫生—流行病学]