Comparison of radiation shielding requirements for HDR brachytherapy using and sources

has received a renewed focus lately as an alternative to sources for high dose rate (HDR) brachytherapy. Following the results of a recent work by our group which proved to be a good candidate for HDR prostate brachytherapy, this work seeks to quantify the radiation shielding requirements for HDR brachytherapy applications in comparison to the corresponding requirements for the current HDR brachytherapy standard. Monte Carlo simulation (MC) is used to obtain and broad beam transmission data through lead and concrete. Results are fitted to an analytical equation which can be used to readily calculate the barrier thickness required to achieve a given dose rate reduction. Shielding requirements for a HDR brachytherapy treatment room facility are presented as a function of distance, occupancy, dose limit, and facility workload, using analytical calculations for both and HDR sources. The barrier thickness required for is lower than that for by a factor of 4–5 for lead and 1.5–2 for concrete. Regarding HDR brachytherapy applications, the lead shielding requirements do not exceed , even in highly conservative case scenarios. This allows for the construction of a lead door in most cases, thus avoiding the construction of a space consuming, specially designed maze. The effects of source structure, attenuation by the patient, and scatter conditions within an actual treatment room on the above‐noted findings are also discussed using corresponding MC simulation results.