Evaluation of the effective energy of primary and transmmitted workload weighted X-ray spectra

abstract Current methods for X-ray shielding evaluation for imaging facilities do not take into account theeffective energy of the radiation impinging on primary barrier. In addition, the X-ray beam attenuationthrough the patient is not considered in radiation shielding. The proposed models do not deal with thehardening of the spectra between the primary and transmitted beams. Therefore, the present workproposes the evaluation of X-ray spectra transmitted by an adult patient (anthropomorphic phantom)and a shielding barrier weighted by typical workload distributions. A set of primary spectra produced bya voltage range from 60 to 140 kV was measured with a CdTe spectrometer system. A second set of X-rayspectra transmitted through a 15 mm thickness barite mortar plate was also measured employing thesame beam quality and voltage range. The air-kerma was simultaneously measured using an ionizationchamber. The primary and transmitted experimental X-ray spectra were weighted by a typical chestexamination workload distribution. The resulting weighted spectra represent the superposition of theradiation beams typically used in chest examinations. The effective energy of primary weighted spectrawas estimated in 42.4 keV and the effective energy of the corresponding transmitted spectra wasestimated in 64.7 keV.& 2013 Elsevier Ltd. All rights reserved.