Hosseini Pooya S M, Dashtipour M R
Radiation Application Research School, Nuclear Science and Technology Research Institute, Tehran, Iran.
Iran Nuclear Regulatory Authority, Tehran, Iran.
Radiat Prot Dosimetry. 2018 Oct 1;181(3):255-260. doi: 10.1093/rpd/ncy021.
According to the worldwide reports, industrial radiography is one of the highest risk radiation practices due to handling high activity sources. Therefore, an optimization of protection along with appropriate investigation level and/or dose constraint is required to achieve appropriate radiological safety. This research, presents some statistical aspects of this optimization using frequency distributions and percentiles of individual recorded dose of industrial radiographers from the years 2002 to 2016 in Iran. The results show that, considering an investigation level of 4 mSv for bimonthly monitoring periods, 3-7% of population of workers has been investigated during these years. Moreover, an overall reduction on average annual and collective doses is observed, despite of the relative increasing in the number of workers. Since the frequency of periodical recorded dose at lower dose range (e.g. <4 mSv) causes greater impacts on the reduction of collective dose than the higher ranges, a retrospective average dose of non-investigated workers can also be substitute with a constant value as a dose constraint. It can be concluded that all the past measures of regulatory body and attempts of the employers have been effective improving the radiological protection in this practice in Iran. However, establishing a dose constraint seems to be essential to continue and improve this optimization of protection.
根据全球报告，由于涉及高活度源的操作，工业射线照相是风险最高的辐射作业之一。因此，需要优化防护措施并设定适当的调查水平和/或剂量约束，以实现适当的放射安全。本研究利用2002年至2016年伊朗工业射线照相人员个人记录剂量的频率分布和百分位数，呈现了这种优化的一些统计情况。结果表明，考虑到每两个月监测期的调查水平为4毫希沃特，这些年有3%至7%的工人接受了调查。此外，尽管工人数量相对增加，但年平均剂量和集体剂量总体有所下降。由于较低剂量范围（如<4毫希沃特）的定期记录剂量频率对集体剂量降低的影响大于较高剂量范围，未接受调查工人的回顾性平均剂量也可用一个恒定值作为剂量约束来替代。可以得出结论，监管机构过去的所有措施以及雇主的努力在改善伊朗这一作业中的放射防护方面都是有效的。然而，设定剂量约束对于继续和改进这种防护优化似乎至关重要。
