Research Center for Radiation Protection, National Institute of Radiological Sciences, Environmental Radiation Effects Research Group, Anagawa 4-9-1, Inage-ku, Chiba 263 8555, Japan.
J Environ Radioact. 2011 Sep;102(9):806-12. doi: 10.1016/j.jenvrad.2011.05.008. Epub 2011 Jun 23.
One of the essential parameters influencing of the dose conversion factor is the ratio of unattached short-lived radon progeny. This may differ from the value identified for indoor conditions when considering special workplaces such as mines. Inevitably, application of the dose conversion factors used in surface workplaces considerably reduces the reliability of dose estimation in the case of mines. This paper surveyed the concentration of radon and its short-lived radon progeny and identified the unattached fraction of short-lived radon progeny. As well equilibrium factor during the month of August was calculated simultaneously at two extraction faces in a manganese ore mine. During working hours the average radon concentrations were 220 Bq m(-3) and 530 Bq m(-3) at Faces 1 and 2; the average short-lived progeny concentration was 90 Bq m(-3) and 190 Bq m(-3), the average equilibrium factors were 0.46 and 0.36, and the average unattached fractions were 0.21 and 0.17, respectively. The calculated dose conversion factor was between 9 and 27 mSv WLM(-1), but higher values could also be possible.
影响剂量转换因子的一个基本参数是短寿命氡子体的非结合比例。当考虑到矿山等特殊工作场所时，这可能与室内条件下确定的值不同。不可避免的是，在矿山情况下，应用表面工作场所使用的剂量转换因子会大大降低剂量估算的可靠性。本文调查了氡及其短寿命子体的浓度，并确定了短寿命子体的非结合部分。同时，在锰矿的两个开采面计算了 8 月期间的平衡因子。在工作时间内，面 1 和面 2 的平均氡浓度分别为 220 Bq/m³和 530 Bq/m³；平均短寿命产物浓度分别为 90 Bq/m³和 190 Bq/m³，平均平衡因子分别为 0.46 和 0.36，平均非结合部分分别为 0.21 和 0.17。计算得到的剂量转换因子在 9 到 27 mSv WLM(-1) 之间，但也可能存在更高的值。
