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1 测量方法 ICRU第39号报告给出了用于环境监测和个人监测的4个实用辐射量:周围剂量当量、定向剂量当量、深部个人剂量当量和浅表个人剂量当量,并建议用这些实用辐射量来校准辐射防护仪器。在提出这些新量的同时,ICRU已考虑到:除了对现有辐射防护仪器的标度名称及其刻度作必要的改变外,仍容许继续使用（或稍加修改）现行的辐射防护仪器的校准方法。目前的辐射防护仪器都是用空气比释动能、照射量或空气吸收剂量作为校准量进行校准的,为使其转化（或再校准）为所要求的剂量当量,就需要乘上一个合适的转换因子（亦称为转换系数）。 实际校准时,仍是沿用通行、常规的方法来确定仪器的校准因子N,即 N=H/M （1）式中M为在已知剂量当量H的校准辐射场中的仪器读数。这种校准是在特定的条件（如ISO推荐的辐射场）下完成的;但是其校准量通常不是剂量当量,因此要求利用所计算的转换因子来求得剂量当量。例如,当校准γ射线巡测仪时,最初的校准量可以是空气比释动能或照射量,那么由空气比释动能或照射量到周围剂量当量的转换因子就用来确定剂量当量。这个转换因子就是上面的校准因子N。
1 Measurement Methods ICRU Report No. 39 gives four useful radiation doses for environmental monitoring and personal monitoring: ambient dose equivalent, directed dose equivalent, deep individual dose equivalent and superficial individual dose equivalent, and recommends using these practical radiation To calibrate the radiation protection equipment. While presenting these new quantities, the ICRU has taken into consideration that, in addition to making the necessary changes to the name and scale of the existing radiation protection equipment, the current calibration of the radiation protection equipment is still allowed to continue (or with minor modifications) method. Current radiation protection devices are calibrated using air kerma, exposure or air absorbed dose as a calibration quantity, and for conversion (or recalibration) to the required dose equivalent, a suitable conversion is required Factor (also known as the conversion factor). In actual calibration, the calibration factor N of the instrument, N = H / M (1), is still used in the conventional way, where M is the reading of the instrument in the calibration radiation field of known dose equivalent H. This calibration is done under certain conditions, such as those recommended by the ISO; however, the calibration is usually not a dose equivalent and therefore requires calculation of the dose equivalent using the calculated conversion factor. For example, when calibrating a gamma-ray surveyor, the initial calibration may be air kerma or exposure and the conversion factor from air kerma or irradiance to ambient dose equivalents is then used to determine the dose equivalent. This conversion factor is the calibration factor N above.