Detailed characterization of respirable coal mine dust is critical to understanding occupational health outcomes, as well as improving exposure monitoring and dust controls in mines. However, data on characteristics such as particle size and mineralogy are still scarce, and there are virtually no datasets available that allow direct comparisons across many mines. Following up on a previous effort to characterize dust from eight underground mines in the Appalachian region of the United States, the current study expands the dataset to cover a total of 25 mines across the country. A total of 171 respirable dust samples were collected in standard locations of each mine and analyzed by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). Results demonstrate that significant differences in particle size and mineralogy distributions exist both within and between mines based on sampling location, mine region and/or mining method–and characteristics can be indicative of dust sources. In locations nearby to production or roof bolting, the respirable dust was clearly sourced from the mine strata. Interestingly, in the production location rock-strata sourced dust appeared to be inordinately abundant relative to the actual coal and rock strata heights being mined during sampling. With respect to particle size, diesel particulates and coal dust were generally found to be finer than mineral dust; and mineral dust likely sourced from the rock strata in the mine was finer than that associated with rock dusting products. On average, when considering all particles analyzed between 100 and 10,000 nm, results indicate that about 75% are in the submicron range, however these particles are estimated to account for only about 6% of the mass.

可吸入煤矿粉尘的详细表征对于了解职业健康结果以及改善矿井中的暴露监测和粉尘控制至关重要。然而，关于粒度和矿物学等特征的数据仍然很少，而且几乎没有可用的数据集可以直接比较许多矿山。继之前对美国阿巴拉契亚地区 8 个地下矿山的粉尘进行表征的努力之后，当前的研究将数据集扩展到覆盖全国总共 25 个矿山。在每个矿山的标准位置共收集了 171 个可吸入粉尘样本，并通过扫描电子显微镜和能量色散 X 射线光谱 (SEM-EDX) 进行了分析。结果表明，根据采样位置、矿区和/或采矿方法，矿井内部和矿井之间在粒度和矿物分布方面存在显着差异——并且特征可以指示粉尘来源。在靠近生产或屋顶螺栓的位置，可吸入粉尘显然来自矿层。有趣的是，与采样期间开采的实际煤层和岩层高度相比，生产地点的岩层来源粉尘似乎异常丰富。在粒度方面，柴油颗粒和煤尘通常比矿物粉尘更细；可能来自矿山岩层的矿物粉尘比与岩粉产品相关的粉尘更细。平均而言，当考虑在 100 到 10 之间分析的所有粒子时，