Interest is increasing in the radiological consequences of a release of aerosol and gaseous iodine, especially after the Fukushima accident and also because of new interpretations of the results of recent severe accident experiments. This work provides a brief review of the history of iodine chemistry in containment and suggests an approach to include gaseous iodine, namely in the forms of elemental iodine and organic iodide, in consequence analyses using the MACCS code. As dry deposition is an important characteristic to distinguish each chemical form of iodine when performing a consequence analysis, the mechanisms and mathematical formulas expressing dry deposition are also investigated. The proposed approach is demonstrated by performing consequence analyses with a unit release of 131I, with the resulting trends of concentration and dose for the different chemical forms of iodine presented and discussed. For the same amount of iodine release, there is a higher surface deposition of elemental iodine (I2) because it has a higher dry deposition velocity, while the air concentration of a representative organic iodide (CH3I) is higher due to its lower dry deposition velocity, which means a lower depletion of the air concentration. Despite elemental iodine having a lower air concentration, its higher dose coefficients for the inhalation pathway compensates for this when calculating doses. Further, inhaled doses increase when considering resuspension inhalation for extended durations of exposure. The approach proposed in this study is expected to be used flexibly to perform consequence analyses incorporating both aerosol and gaseous forms of iodine.

中文翻译：

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一种在放射线后果分析中纳入多种形式的碘的方法。

气溶胶和气态碘释放的放射学后果越来越引起人们的关注，特别是在福岛事故之后，以及对最近的严重事故实验结果的新解释。这项工作简要回顾了围堵中碘化学的历史，并提出了一种使用MACCS代码进行后果分析的方法，以包括气态碘，即元素碘和有机碘的形式。由于干沉积是进行结果分析时区分每种化学形式的碘的重要特征，因此还研究了表示干沉积的机理和数学公式。通过对131I单元释放进行结果分析来证明所提出的方法，提出并讨论了不同化学形式的碘的浓度和剂量趋势。对于相同量的碘释放，元素碘（I2）的表面沉积较高，因为它具有较高的干沉积速度，而代表性有机碘（CH3I）的空气浓度则由于其较低的干沉积速度而较高，这意味着空气浓度降低。尽管元素碘的空气浓度较低，但在计算剂量时，其较高的吸入途径剂量系数可以对此进行补偿。此外，在延长接触时间时考虑重新悬浮吸入时，吸入剂量会增加。