β-γ混合辐射场中定向剂量当量率Ḣ'(0.07)的监测方法研究OA

To address the challenge of accurately determining the directional dose equivalent rate Ḣ'(0.07)in β-γ mixed radiation fields,a novel measurement methodology is proposed.This approach integrates measurements from ambient dose equivalent rate monitors,directional dose equivalent rate monitors,β spectrometers,and γ spectrometers.A β-γ mixed standard radiation field was established to verify this method.Following application of the methodology proposed in this study,the relative error between the measured Ḣ'(0.07,45°)value and the reference value traceable to a certified standard instrument was reduced from 13.0％to 2.69％,verifying the method's reliability.In field applications,Ḣ'(0.07)was measured and data were processed at 14 locations exposed to β-γ mixed radiation fields during the No.106 overhaul of Hainan nuclear power plant.The measured Ḣ'(0.07)/H ∗(10)ratios ranged from 2.06 to 29.1,with a mean value of 9.64—indicating that Ḣ'(0.07)was,on average,approximately one order of magnitude greater than Ḣ*(10).Accurate quantification of Ḣ'(0.07)in β-γ mixed fields is therefore essential for reliable assessment of occupational exposure risk and provides critical input for radiation protection decision-making in nuclear facilities.