Dean M H, Stedeford B
Phys Med Biol. 1984 Jun;29(6):711-8. doi: 10.1088/0031-9155/29/6/007.
Radiation streaming down gaps between shielding windows and walls of radiotherapy treatment rooms has been investigated. The calculations were based on a cobalt-60 source and were performed with the computer code RANKERN. The dose rate near the exit of the gap on the cold side of the window was calculated as the sum of contributions from direct line of sight and radiation scattered off the faces of the gap, using albedo data. The RANKERN code employs point kernel equations which are solved by a stochastic integration method. The paper demonstrates that although for a single element window small gaps could lead to significant leakage of radiation, for a double or triple element window, even a gap of ten millimetres would result in a dose rate no greater than that through the surrounding concrete.
对放射治疗室屏蔽窗与墙壁之间缝隙中泄漏的辐射进行了研究。计算基于钴 - 60源，并使用计算机代码RANKERN进行。利用反照率数据，将窗冷侧缝隙出口附近的剂量率计算为直接视线贡献与从缝隙表面散射的辐射贡献之和。RANKERN代码采用点核方程，通过随机积分方法求解。本文表明，虽然对于单元素窗口，小缝隙可能导致显著的辐射泄漏，但对于双元素或三元素窗口，即使十毫米的缝隙导致的剂量率也不会高于周围混凝土的剂量率。
