| Summary: | 碩士 === 國立清華大學 === 生醫工程與環境科學系 === 102 === Personal dose equivalent, Hp(d) defined by the International Commission on Radiation Units and Measurements, were commonly regarded as conservative surrogates of effective dose and equivalent dose of lens and skin. The study checked the valid of the assumption by experiments. E, effective dose was measured with RANDO phantom and TL system according to ICRP Recommendations. Hp(d) were measured with two kinds of dosimetry badges, Harshaw TLD dosimeters and Landauer OSLD dosimeters. The conversion coefficients of E/Hp(d) and HT/ Hp(d) were calculated which concerned irradiation by different photon energies (80 kV to10 MV)and irradiation geometries(AP, PA, RLAT, LLAT). The variance of conversion coefficients with five dosimeter positions in front of the torso which the radiation workers often wear on were discussed. The study also compared the conversion coefficients in this experiment with the published data which were simulated by Monte Carlo N-Particle code. The result showed that Hp(d) underestimate the effective dose and equivalent dose of lens and skin in some photon energies, especially low energies and some unfavorable geometries. And this study shows that defect of LAT geometry in the published data which was simulated.
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