β射线表面污染测量中去除γ场干扰的两种方法比较  

Comparison of Two Methods of γ-Radiation Disturbance Removal in β-radioactive Surface Contamination Measurement

作　　者：赵飞[1] 孙彦泽[1] 文万信[1] 

机构地区：[1]苏州大学医学部放射医学与公共卫生学院放射卫生学教研室,江苏苏州215123

出　　处：《苏州大学学报（医学版）》2011年第3期357-360,共4页Suzhou University Journal of Medical Science

摘　　要：目的研究在测量β射线表面污染时使用遮挡法和距离法去除γ场干扰的效果。方法采用遮挡法和距离法对几种常见放射源及某放射性工作场所进行了测量,通过比较使用这两种方法前后仪器的计数差别来判断有无干扰。结果如存在干扰,测量时使用遮挡法前后计数有显著差异(P<0.01);使用距离法前后计数也有显著差异(P<0.01),但存在假阳性。结论使用遮挡法能够定性地、快速地判断被测场所β射线表面污染数据的有效性,进一步给出处理建议;而对于距离法,存在一定的适用范围:在被测场所的γ场近似均匀的情况下可以参考此方法,否则不适用。Objective To study two methods＇ effectiveness of removing the γ-interference in β-surface contamination measurement.Methods Masking and distancing were used alternately in the measurements of several radioactive sources and workshop ground surface.The meter counts difference was compared before and after the methods separately,we can infer whether γ-interference exists.Results If interference exists,there is remarkable difference after using masking（P0.01）,and that difference also appears after using distancing（P0.01）,but not all the situation.Conclusion Masking can be taken as an effective method to judge the validity of measured data qualitatively and quickly,furthermore,to give recommendations to the next step.As for the method of distancing,the scope of its application is confined only in the homogeneous γ-radiation field;otherwise the method is inadvisable.

关 键 词：放射性表面污染测量 γ射线干扰 遮挡法 距离法 

分 类 号：R145[医药卫生—公共卫生与预防医学] X591[环境科学与工程—环境工程]