Monte Carlo verification of the holder correction factors for the radiophotoluminescent glass dosimeter used by the IAEA in international dosimetry audits

The International Atomic Energy Agency (IAEA), jointly with the World Health Organization (WHO), has operated a postal dosimetry audit program for radiotherapy centers worldwide since 1969. In 2017 IAEA introduced new methodology based on radiophotoluminescent (RPLD) these audits. detection system consists of phosphate glass dosimeter inserted in plastic capsule that is kept measuring position PMMA holder during irradiation. Correction factors this were obtained using experimental methods. work methods are described and resulting verified by means Monte Carlo simulation general-purpose code PENELOPE range photon beam qualities relevant radiotherapy. study relies detailed geometrical representation setup. Various beams from faithful modeling corresponding linacs. transport parameters selected to ensure subpercent accuracy. simulated correction fall interval 1.005–1.008 (±0.2%), deviations respect values not larger than 0.2(2)%. This corroborates validity currently used