44. 对一般风险管理而言，为了管理目的，并为了能够与其他辐射照射来源进行比较，需要一个计算某次特定的氡照射剂量的系数。有两种方法可以产生这种所谓的剂量系数。“剂量测定方法”根据与氡及其衰变产品有关的大气和呼吸特征来计算某次氡照射的剂量。辐防委员会使用了从流行病学研究导出系数的“流行病学方法”，即是使用矿工中的肺癌风险相对于原子弹爆炸幸存者总体癌症风险的比率。在委员会 2000 年的报告中，这两种方法产生的结果大约相
44. For general risk management, a factor for calculating the dose from a given exposure to radon is needed for regulatory purposes and to allow comparison with other sources of radiation exposure. There are two approaches for deriving this so-called dose factor. A “dosimetric approach” derives the dose from a given exposure on the basis of atmospheric and breathing characteristics relevant for radon and its decay products. An “epidemiological approach” has been used by ICRP to derive the factor from epidemiological studies using the ratio of the risk of lung cancer in miners to the overall risk of cancer in the atomic bombing survivors. In the Committee’s 2000 report there appeared to be a difference of a factor of about two between the results for the two approaches. However, the most recent data published on the risks to underground miners (derived from updated studies of cohorts of uranium miners) suggest that the results for the two approaches are less different than initially thought. Nonetheless, more work is necessary to better understand and account for the influence of modifying factors—such as the time since exposure, the attained age and the influence of dose rate—and of confounding factors (especially tobacco smoking).