“影锥法”是实验上定量测量散射大小的常用方法,具体做法是采用适当大小的铅块放置在放射源和探测器之间,铅块应足够厚,以便能完全遮挡放射源对探测器的直射贡献,此时探测器所记录的辐射剂量率全部来自于散射,进而能定量得出散射光子的辐射剂量,图1为“影锥法”装置实例,测量结果列于表1。由表1可知,“影锥法”测量的散射辐射剂量率占总剂量率的不足1%,满足GB/T 12162.1—2000的设计要求。 The “shadow cone method” is a commonly used method for quantitatively measuring the amount of scattering experimentally by placing a lead block of appropriate size between a radioactive source and a detector, and the lead block should be thick enough to completely block the radioactive source The direct contribution of the detector, the detector at this time the radiation dose rate recorded by all from the scattering, and then be able to quantitatively determine the radiation dose of scattered photons, Figure 1 for the “shadow cone method” device example, the measurement results are shown in Table 1. From Table 1 shows, “shadow cone method ” measured scattered radiation dose rate of less than 1% of the total dose rate to meet the design requirements GB / T 12162.1-2000.