The purpose of this work was to determine the transition coefficients from measured values in practice – air kerma or ambient dose equivalent to the effective dose of radiation on inspection systems using X-ray radiation, in particular, for the installation «Sibscan». This paper presents the results of Monte Carlo calculations using the GEANT4 simulation package and the MIRD and ICRP anthropomorphic phantoms. It was shown that when calculations are based on measurements of the kerma in the air, it is necessary to use the multiplier 1.05 (Sv/Gy) when a person is irradiated in anteroposterior projection and 0.65 (Sv/Gy) in posteroanterior projection. In calculations based on measurements of the ambient dose equivalent H*(10), it is necessary to take into account the conversion constant H*(10)/Kerma, equal to 1.62 (Sv/Gy) and use the coefficients 0.65 (Sv/Sv) and 0.4 (Sv/Sv) in the specified projections respectively. For a more accurate determination of the effective dose, it is necessary to take into account a larger set of technical parameters of the system. Thus, it is necessary to declare not only the maximum voltage at the radiation source but also the thickness of the half-attenuation layer in aluminum as a measure of the applied photon radiation filtering. The obtained coefficients could be used in estimating the effective radiation doses on real installations.
Ambient Dose Equivalent versus Effective Dose for Quantifying Stray Radiation Exposures to a Patient Receiving Proton Therapy for Prostate Cancer