Measurement and Uncertainty Analysis of Air Kerma Strength for Afterloading Radioactive
Source 192Ir
LUO Bin1, LI Xianfu1, CAO Lu1, JIANG Wei2, GUO Fei1, XIE Li1, YANG Huadong1, XU Peng1
1. Department of Oncology, Affiliated Hospital of North Sichuan Medical College, Nanchong Sichuan 637000, China;
2. Jiangsu Institute of Metrology, Nanjing Jiangsu 210023, China
Abstract：Objective To analyze and verify the air kerma strength of after loading radioactive source 192Ir, explore the various sources
of uncertainties in the measurement process of the well-type ionization chamber method, and evaluate the expanded uncertainties.
Methods Firstly, the air kerma strength of the 192Ir source according to the guidance of the well-type ionization chamber method were
measured. Based on the completion of the verification, the corresponding mathematical model was established. Then the extended
uncertainty of the measurement results was calculated by comprehensive application of class A or class B uncertainty evaluation.
Results Among the 34 measurement calculation, the relative errors between the measured data and the planning system calculated
data of the three 192Ir source in our hospital were all met the standard of AAPM clinical application of less than ±3%. There was no
statistically difference between them (P>0.05), and the expanded uncertainty of the measurement result was 4.1% (k=2).
Conclusion The well-type ionization chamber method can accurately measure the air kerma strength of the 192Ir source. The largest
influencing factor of the expanded uncertainty of this method is the calibration factor of the reference air kerma rate of the well-type
ionization chamber.
罗斌1，李贤富1，曹璐1，蒋伟2，郭飞1，谢力1，阳华东1，许鹏1. 后装192Ir放射源空气比释动能强度的
测量及不确定度分析[J]. 中国医疗设备, 2023, 38(4): 56-60.
LUO Bin1, LI Xianfu1, CAO Lu1, JIANG Wei2, GUO Fei1, XIE Li1, YANG Huadong1, XU Peng1. Measurement and Uncertainty Analysis of Air Kerma Strength for Afterloading Radioactive
Source 192Ir. China Medical Devices, 2023, 38(4): 56-60.
