IBMEC, Faculty of Engineering, Rio de Janeiro, Brazil.
Defense Engineering Graduate Program, Military Institute of Engineering, Rio de Janeiro, Brazil.
J Environ Radioact. 2019 Nov;208-209:106034. doi: 10.1016/j.jenvrad.2019.106034. Epub 2019 Aug 24.
A radiological dispersal device (RDD) is built using an explosive device laced with radioactive materials. The RDD appears as a speculative radiological weapon with the aim of spreading radioactive material across an inhabited area. This study seeks to evaluate how the official decision-making process is influenced by the radiation vertical profile dose, using the hypothetical scenario of a simulated RDD detonation in a densely populated urban area. A simulated plume of strong radiation was generated from the explosion site, contaminating the surrounding area. Several atmospheric conditions impact on the contamination. However, this study focusses on the following main variables considered by HotSpot for a conservative simulation: (a) the atmospheric stability conditions (Pasquill-Gifford - PG classes); (b) the explosive power, and (c) the source-term. Gaussian modeling was used for its speed, and for its capacity to estimate the time-integrated atmospheric concentration of an aerosol at any point in 3D space. The simulation provided information about four main outcomes: (a) contamination plume area; (b) radiological risk dependency on PG classes; (c) total effective dose equivalent (TEDE) with a possible dependence on receptor height; and (d) potentially affected population's size. The findings suggest that a protocolled response from authorities should be implemented in order to effectively follow possible changes in the PG class. Which, in turn, may negatively impact the decision-making process.
放射性弥散装置（RDD）是使用带有放射性物质的爆炸装置构建的。RDD 作为一种推测性的放射性武器，旨在将放射性物质散布到有人居住的区域。本研究旨在评估官方决策过程如何受到辐射垂直剖面剂量的影响，使用模拟 RDD 在人口密集的城市地区爆炸的假设场景。从爆炸现场产生了一股强烈辐射的模拟羽流，污染了周围区域。几个大气条件会对污染产生影响。然而，本研究主要关注 HotSpot 进行保守模拟时考虑的以下主要变量：（a）大气稳定条件（Pasquill-Gifford-PG 类）；（b）爆炸威力；（c）源项。高斯模型因其速度和能够估算气溶胶在 3D 空间中任何点的时间积分大气浓度而被使用。该模拟提供了关于四个主要结果的信息：（a）污染羽流区域；（b）放射性风险对 PG 类别的依赖性；（c）总有效剂量当量（TEDE）可能取决于受体高度；（d）可能受影响的人口规模。研究结果表明，当局应实施既定的应对措施，以便有效地跟踪 PG 类别的可能变化。这反过来可能会对决策过程产生负面影响。
