10 MV医用直线加速器防护门外辐射剂量简易估算模式

A Simple Method for Evaluating Radiation Dose Outside Protective Door of 10 MV Medical Linear Accelerator

目的研究并提出一种10 MV光子束医用直线加速器机房防护门外辐射剂量简易估算模式。方法分别计算6 MV、10 MV不同能量和不同迷路内墙厚度条件下防护门外的辐射剂量水平,对计算结果进行分析,再根据分析结果提出新的简易估算模式。结果6 MV、10 MV两种不同能量状态下防护门外辐射剂量大小与迷路内墙的厚度有关。采用“6 MV能量下(H_(PS)+H_(S)+H_(LS))+10 MV能量下(H_(L))”简易模式,计算与评价防护门外的辐射剂量,其结果如符合标准规定限值要求,则6 MV、10 MV两种不同能量下各自的辐射剂量也必然符合限值要求。结论采用本文提出的简易估算模式,有效减少了计算量,提高了计算与评价的效率,可为从事医用直线加速器防护设计、评价机构以及管理部门提供技术参考。

Objective To study and propose a simple radiation dose evaluating model for 10 MV photon beam medical linear accelerator.Methods The radiation dose level outside the protective door was calculated under the conditions of 6 MV,10 MV different energy and different labyrinth inner wall thickness.The calculation results were analyzed,and then a new simple estimation model was proposed according to the analysis results.Results The radiation dose outside the protective door was related to the thickness of the labyrinth wall at 6 MV and 10 MV.The simple mode of“6 MV energy(HPS+HS+HLS)+10 MV energy(HL)”was adopted to calculate and evaluate the radiation dose outside the protective door.If the results met the limit requirements of the stipulated standard,the radiation dose under 6 MV and 10 MV energy must also meet the limit requirements.Conclusion The simple evaluating model proposed in this paper can effectively reduce the amount of calculation,improve the efficiency of calculation and evaluation,and provide technical reference for the protection design,evaluation institutions and management departments of medical linear accelerators.