【作者】 王志佳； 陈大伟；

【机构】 吉林大学公共卫生学院；

【摘要】 目的:对320排容积CT(Aquilion ONE)的机房进行屏蔽设计,使其能够达到有效屏蔽,使职业人员以及公众成员受到的辐射达到我国GBZ/T180对CT机房规定剂量目标值以下,确保职业人员以及公众成员在机房周围地区的留居是安全的。方法:根据NCRP推荐的CT剂量长度乘积(DLP)负荷法。DLP乘以一个常数,给出距机架等中心d米处散射的空气比释动能近似关系,根据每天检查患者数,计算出相应周工作负荷和在待测d点上的每周散射的空气比释动能数值,求出在待测d点上透射函数B值,通过查相应Pb(或混凝土)厚度与B关系曲线得到屏蔽材料厚度。结果:经计算得出,待设计机房的四周墙壁分别需要0.23、0.38、0.75、0.57(mm)厚的铅或28、44、73、64(mm)厚的混凝土。结论:待设计机房的墙壁至少需要0.23、0.38、0.75、0.57(mm)厚的铅或28、44、73、64(mm)厚的混凝土才能够达到有效屏蔽,能够确保职业人员以及公众成员在机房周围地区的留居是安全的。更多还原

【Abstract】 Objective:To design a machine room for 320-slice volumetric CT by calculating the thickness of wall in accordance with protection standard of GBZ/T180,in order to make sure that people around the machine room are safe.Methods:Use CT dose-length product(DLP) method that NCRP recommended.DLP multiplied by a constant approximately equals to the air kerma on d spot.Work out the corresponding workload per week and the value of the scattering air kerma per week on d spot.After the transmission function B is obtained,the thickness of shielding materials can be calculated by looking up the table of the relation curve between Pb or concrete with B.Resuhs:The walls of the machine room to be designed respectively need 0.23、0.38、0.75、0.57(mm)Pb or 28、44、73、64(mm) concrete. Conclusion:O.23、0.38、0.75、0.57(mm)Pb or 28、44、73、64(mm) concrete is required to make sure that people around the machine room are safe.更多还原