某质子回旋加速器治疗装备研发调试厂房的辐射屏蔽探讨

目的 探讨质子回旋加速器治疗装备研发调试厂房在不同调试阶段的辐射屏蔽优化方案。方法 根据不同调试阶段的最大源项，采用经验公式估算调试厂房屏蔽体外关注点的瞬时剂量率，对调试厂房各调试阶段的屏蔽进行优化。结果 回旋加速器调试阶段在墙3和墙4内分别设置1.0 m、1.0 m的移动混凝土屏蔽块，束流输运线调试阶段在墙4和墙5内分别设置1.0 m、1.25 m移动混凝土屏蔽块，模拟治疗室调试阶段在墙9外设置1.0 m、屋顶设置0.4 m的移动混凝土屏蔽块，屏蔽体外关注点的剂量率可满足相关剂量率控制限值的要求。结论 移动混凝土屏蔽块的设置在满足屏蔽效果的同时也考虑了经济性及厂房空间要求，符合防护最优化原则；可作为高能粒子加速器类研发或类似科研项目辐射屏蔽优化的一种解决方案。

Discussion of radiation shielding optimization for proton cyclotron therapy system plants

Objective To explore the radiation shielding optimization plan for a medical proton cyclotron developing and commissioning building at various commissioning stages.Methods According to the maximum source termsat different commissioning stages, we used the empirical formula to estimate the instantaneous dose rate at the point of interest outside the shield of the building, and optimized the building’s shielding ateach commissioning stage.Results When adding 1.0 m mobile concrete shielding blocks (“blocks” below) each to wall 3 and wall 4 at the cyclotron commissioning stage, 1.0 m blocks to wall 4 and 1.25 m blocks to wall 5 at the beam transport line commissioning stage, and 1.0 m blocks to wall 9 and 0.4 m blocks to the ceiling at the simulated treatment room commissioning stage, the dose rates at the points of interest outside the shield could meet the dose rate limit requirements.Conclusion The application of mobile concrete shielding blocks not only meets the shielding requirements, but also has economical and space-saving advantages, conforming to the principle of shielding optimization. This can be an approach to the optimization of radiation shielding for high-energy particle accelerators or similar scientific projects.