Size distributions of airborne fibres generated from man-made mineral fibre products.
Size distributions of airborne fibres generated from man-made mineral fibre products.
复制标题
人造矿物纤维产品产生的气载纤维的尺寸分布。
DOI：
10.1093/annhyg/27.2.157
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
J. Skotte
中科院分区：
文献类型：
--
作者：
T. Schneider;E. Holst;J. Skotte
空气尘埃样品中纤维的最终尺寸分布是几个因素的结果：（a）制造过程给出了一定的直径分布;制造商通常确定这种直径分布（中值被称为标称直径）。（B）据认为，这种累积长度直径分布可以不变地进入分散状态，例如在锯切期间，（c）以通常的方式通过对纤维进行计数来对这种分散的粉尘中的纤维进行分级，导致与标称直径相比，中值直径明显减小。在假定粉尘的长度和直径服从对数正态分布的基础上，给出了降尘的数学公式。（4）沉降和通风使粉尘的分布进一步向小直径方向移动。根据一个假定搅拌沉降和纤维均匀分散的模型进行的计算表明，通风条件和大量样品中直径的几何标准偏差对所得到的稳态粉尘云直径分布的影响与标称直径的典型变化一样大。空气供应和排气以及纤维生产时间的变化估计对这些一般结论的影响很小，特别是如果考虑长期的个人暴露，（e）估计了用于纤维常规评价的取样器的影响。每cm ~ 3纤维的总长度和累积长度直径分布被认为是一个有用的预测健康风险，这个预测是密切相关的散装材料和纤维的空气动力学性能。
The ultimate size distribution of fibres in a sample of airborne dust is the result of several factors: (a) Manufacturing processes give a certain distribution of diameters; manufacturers often determine this diameter distribution (the median is termed the nominal diameter) by the accumulated length method, (b) This accumulated length diameter distribution, it is argued, can go unchanged into the dispersed state, e.g. during sawing, (c) The sizing of fibres in this dispersed dust in the usual way by counting fibres by number causes an apparent reduction in the median diameter as compared with the nominal diameter. A mathematical formula for this reduction is given based on the assumption that length and diameter of the dispersed dust are bivariate log-normally distributed, (d) Settling and ventilation further shift the distribution towards lower diameters. Calculations based on a model assuming stirred settling and uniform fibre dispersion show that ventilation conditions and geometric standard deviation of diameters in the bulk sample influence the resulting diameter distribution of the steady-state dust cloud as much as typical variations in nominal diameters, (e) Influences from spatial variations of fibre production, air supply and exhaust as well as variation in time of fibre production are estimated to have a minor effect on these general conclusions especially if long-term personal exposure is considered, (e) The influence from a sampler used for routine evaluation of fibres is estimated. The total length of fibres per cm3and the accumulated length diameter distribution is suggested to be a useful predictor of health risk and this predictor is closely related to the bulk material and the aerodynamic properties of fibres.