Lead-free Gamma-ray shielding: Comparative analysis of elastomeric and fluoro-rubber materials using FLUKA and EGSnrc simulations

Gamma-ray shielding without lead remains a critical challenge in various industries due to the potential health hazards posed by ionizing radiation. This study addresses the need for effective, flexible shielding materials by investigating the radiation attenuation properties of commercial rubbers. Monte Carlo simulations using FLUKA and EGSnrc codes analyze various elastomers and fluoro-rubbers across photon energies ranging from 59.5 to 1408 keV. Polychloroprene (CR), epichlorohydrin (ECO), and chlorosulfonated polyethylene (CSPE) rubbers were found to be highly efficient in the energy range of 59.5-80.9 keV. In contrast, elastomers with lower densities such as natural rubber (NR), silicone rubber (SR), ethylene propylene diene rubber (EPDM), styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), exhibit superior radioprotective properties within the energy range of 244.7-1408 keV. Moreover, linear attenuation coefficient (μ), mean free path (MFP), half-value layer (HVL), and tenth-value layer (TVL) were considered to determine the most effective polymer for reducing gamma photon penetration. While fluorocarbon rubber (FR) demonstrated superior attenuation owing to its high density, the examination of exposure build-up factors (EBF) highlights ECO, CSPE, and CR as promising shielding media for gamma radiation sources with energy below 0.3 MeV. This study provides a comprehensive assessment of the suitability of various rubber materials for gamma radiation shielding, offering valuable data and insights for technological applications and scientific fields of radiation chemistry