60Co源辐照场人员剂量评估与辐射防护研究OA

To assess the potential radiation accident risks faced by workers in food irradiation processing,a computational model incorporating a 60Co source,irradiation chamber,and adult-male voxel phantom was established using the Monte Carlo method.The absorbed dose rate distribution at detection points outside the shielding wall under accident conditions was systematically analyzed,together with the absorbed doses and organ equivalent doses for indoor personnel under various exposure geometries.Microstructural characterization and shielding performance evaluation of SEBS/(W+Bi)composites were also conducted.The results indicate that under accident conditions,the annual effective dose to outdoor workers remains below the national regulatory limit of 5 mSv·a-1.In contrast,indoor workers without protection may receive exceed-limit doses during shor-term exposure,with the thyroid exhibiting the highest equivalent dose of 2.57×10-19 Sv under right-lateral irradiation.To mitigate high-dose regions,a composite shielding layer with a SEBS-to-W/Bi mass ratio of 1∶2 was designed.This composite exhibits good shielding performance while maintaining good mechanical properties and interfacial compatibility.The results provide a scientific basis for safety assessment of irradiation facilities and optimization of personal protective equipment.