Rez Peter, Metzger Robert L, Mossman Kenneth L
Department of Physics, Arizona State University, Tempe, AZ 85287-1504, USA.
Radiat Prot Dosimetry. 2011 Apr;145(1):75-81. doi: 10.1093/rpd/ncq358. Epub 2010 Nov 9.
Systems based on the detection of Compton backscattered X rays have been deployed for screening personnel for weapons and explosives. Similar principles are used for screening vehicles at border-crossing points. Based on well-established scattering cross sections and absorption coefficients in conjunction with reasonable estimates of the image contrast and resolution, the entrance skin dose and the dose at a depth of 1 cm can be calculated. The effective dose can be estimated using the same conversion coefficients as used to convert exposure measurements to the effective dose. It is shown that the effective dose is highly dependent on image resolution (i.e. pixel size).The effective doses for personnel screening systems are unlikely to be in compliance with the American National Standards Institute standard NS 43.17 unless the pixel sizes are >4 mm. Nevertheless, calculated effective doses are well below doses associated with health effects.
基于康普顿背散射X射线检测的系统已被用于对人员进行武器和爆炸物筛查。类似的原理也用于在边境口岸对车辆进行筛查。根据既定的散射截面和吸收系数，结合对图像对比度和分辨率的合理估计，可以计算出入射皮肤剂量和1厘米深度处的剂量。有效剂量可以使用与将照射测量值转换为有效剂量相同的转换系数来估算。结果表明，有效剂量高度依赖于图像分辨率（即像素大小）。除非像素尺寸大于4毫米，否则人员筛查系统的有效剂量不太可能符合美国国家标准学会标准NS 43.17。然而，计算出的有效剂量远低于与健康影响相关的剂量。
