积分法评估回收^(192)Ir工业探伤源操作人员有效剂量

The Effective Dose of Recovering ^(192)Ir Industrial Radiography Source Operator Evaluated by Integral Method

为了评估回收192Ir工业探伤源操作人员有效剂量,根据南京2014年192Ir源辐射事故场景,利用MCNP程序构建男性MIRD人体模型、192Ir工业探伤源模型,对回收放射源操作人员在电离辐射场的吸收剂量率进行了计算;按指数衰减律拟合出吸收剂量率随一维空间变化的曲线和函数;采用积分法对操作人员手持1 m长柄工具,以2 m/s匀速靠近、夹起、转移放射源、将放射源放入铅屏蔽容器的回收过程的有效剂量进行了计算。结果表明:操作人员回收放射源操作,共花费时间为125 s,整个过程受照有效剂量为1.67 m Sv,与相关文献中个人剂量计的检测数值相吻合。

In order to evaluate the effective dose of operator who recovered Iridium-192（^192 Ir） industrial radiography source,the MIRD human Phantom and^192 Ir source model which base on Nanjing^192 Ir source radiation accident scene in 2014 were constructed by MCNP code. The absorbed dose rate of the operator who recovered radioactive source in ionizing radiation field was calculated as well. According to the exponential decay law,the curves and functions of dose-rate varies with one-dimensional space were fitted at the same time. The effective dose for the operator who held one meter long-handled tools and close to the radioactive sources at 2 m/s speed,picked up,transferred radioactive sources,and put it into the lead shielding container was calculated by integral method. The results showed that it took 125 seconds for the operator to recover the radioactive source and operator irradiated 1. 67 m Sv effective dose in the whole process,which was consistent with the detection value of the personal dosimeter in the related literatures.