Ahangari R, Noori-Kalkhoran O
Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran.
Faculty of Engineering, Shahid Beheshti University, Tehran, Iran.
Radiat Environ Biophys. 2019 May;58(2):277-285. doi: 10.1007/s00411-018-00775-w. Epub 2019 Jan 8.
In this work, protective actions have been studied assuming a hypothetical severe accident of the Bushehr nuclear power plant at different meteorological conditions. Simulations of the atmospheric dispersion of accidental airborne releases were performed using the RASCAL code. Total effective dose equivalent (TEDE) and thyroid dose received by members of the public living within a radius of 40 km around the reactor site were calculated for various atmospheric stability classes and weather conditions. According to the results of the dose assessment and by following the protective action guide of the Environmental Protection Agency (EPA), the critical zone and appropriate protective actions were determined depending on various metrological conditions. It was found that, for atmospheric stability class F and calm weather conditions, the maximum distance from the site of release for which TEDE is greater than the corresponding dose limit and for which sheltering or evacuation response actions are required, is 11 km. For the same weather conditions, the corresponding maximum distance for which iodine prophylaxis is required is 32 km. Based on the present simulations, it can be concluded that the metrological condition has a great influence on the radionuclide atmospheric dispersion and, consequently, on the critical zone where protective actions are required after the assumed accident condition.
在这项工作中,假设布什尔核电站发生假想的严重事故,研究了在不同气象条件下的防护行动。使用RASCAL代码对事故性空气传播释放的大气扩散进行了模拟。针对反应堆场址周围40公里半径范围内居住的公众成员,计算了各种大气稳定度类别和天气条件下的总有效剂量当量(TEDE)和甲状腺剂量。根据剂量评估结果,并遵循环境保护局(EPA)的防护行动指南,根据各种气象条件确定了关键区域和适当的防护行动。结果发现,对于大气稳定度类别F和平静天气条件,TEDE大于相应剂量限值且需要采取掩蔽或疏散应对行动的释放场址的最大距离为11公里。对于相同的天气条件,需要进行碘预防的相应最大距离为32公里。基于目前的模拟,可以得出结论,气象条件对放射性核素的大气扩散有很大影响,因此,对假设事故条件后需要采取防护行动的关键区域也有很大影响。