Fires and explosions in pyrotechnics retail markets recur worldwide with predictable regularity, killing dozens to hundreds of people in single events. This paper argues that the global topology of the market is the dominant determinant of mortality, acting through two independent geometric channels. The first, propagation, concerns ballistic dispersal of ignited articles: the probability that fire spreads between blocks scales with the spatial density of blocks within the dispersal range. The second, evacuation, concerns the distance an occupant must traverse to reach the perimeter, which is set by the global geometry of the market footprint, not by any stall-level parameter. Because mortality risk grows approximately exponentially in evacuation time, topology amplifies modest differences in egress distance into large differences in casualties. Current standards in the United States, the European Union, and Mexico prescribe local parameters such as aisle width and stall separation, but leave the global topology of the market unregulated. We argue that topology should be a regulable design variable, and propose a market geometry that simultaneously slows propagation and shortens evacuation, derived from contact-process models of seed dispersal in spatial ecology.

翻译：全球各地的烟火零售市场反复发生火灾和爆炸，此类事件具有可预测的规律性，单次事故可导致数十至数百人死亡。本文认为，市场的整体拓扑结构是决定死亡率的主要因素，并通过两个独立的几何通道发挥作用。其一为传播效应，涉及点燃物品的弹道散落：火势在不同摊位间蔓延的概率，与散落范围内摊位的空间密度成正比。其二为疏散效应，涉及人员必须穿越到达市场边缘的距离，该距离由市场占地范围的全局几何结构决定，而非任何摊位级别的参数。由于死亡风险大致随疏散时间呈指数增长，拓扑结构将疏散距离上的微小差异放大为伤亡人数的巨大差异。美国、欧盟及墨西哥的现行标准仅规定了通道宽度、摊位间距等局部参数，但未对市场的全局拓扑结构加以约束。我们认为，拓扑结构应成为可监管的设计变量，并借鉴空间生态学中种子传播的接触过程模型，提出一种既能减缓火势传播又能缩短疏散距离的市场几何设计方案。