放射治疗机房主屏蔽墙宽度的计算方法研究  

The Research of Calculating the Primary Barrier Width for Radiotherapy Room

作　　者：鲁旭尉[1] LU Xu-wei(Hunan Cancer Hopital, Changsha 410013 China.)

机构地区：[1]湖南省肿瘤医院,湖南长沙410013

出　　处：《中国辐射卫生》2017年第2期177-180,共4页Chinese Journal of Radiological Health

摘　　要：目的探讨放射治疗机房中有用束主屏蔽区的宽度的计算方法。方法按照国家标准《放射治疗机房的辐射屏蔽规范》计算出有用束主屏蔽区的宽度,与准直器角度为45°,机架角为135°时的治疗束到墙最大射野宽度比较;并在某医院加速器机房实测辐射防护。结果按照国家标准计算的有用束主屏蔽区宽度比最大射野宽度小,理论上存在射线泄露区域,实测结果也证实理论上的射线泄露区域确实存在。结论国家标准中放射治疗机房的有用束主屏蔽区的宽度计算方法及监测条件仅仅考虑机架角为90°、180°或者270°的情况,考虑的情况不足,存在防护漏洞。据此本文推导出正确的有用束主屏蔽区的宽度计算方法,并给出已建放射治疗机房的补救方法。Objective To discuss the method for calculating the primary barrier width of primary beam in radiotherapy room.Methods We calculated the primary barrier width of primary beam using the method listed in the national standard of “radiation shielding requirements in room of radiotherapy installations”,and then compared with the largest width from beam to wall when collimator angle is 45 degrees and the gantry angle is 135 degrees.Moreover,we tested radiation shielding in radiotherapy room of one hospital.Results According to the national standard,the area of exposure to X-ray does not theoretically but actually exist.Conclusion The method listed in the national standard for calculating the primary barrier width of primary beam only takes into account that when the gantry angle is 90°,180° or 270°,which is not sufficient and may cause loopholes in radiation shielding.We recommended the appropriate method for calculating the primary barrier width of primary beam,and the salvage method for radiotherapy rooms which are already built.

关 键 词：国家标准 放射治疗机房 放射防护 

分 类 号：R142[医药卫生—公共卫生与预防医学]