Føreland Solveig, Bakke Berit, Vermeulen Roel, Bye Erik, Eduard Wijnand
National Institute of Occupational Health, Oslo, Norway.
Ann Occup Hyg. 2013 May;57(4):417-31. doi: 10.1093/annhyg/mes086. Epub 2012 Dec 1.
The aim of this study was to identify important determinants of dust exposure in the Norwegian silicon carbide (SiC) industry and to suggest possible control measures.
Exposure to total dust, respirable dust, quartz, cristobalite, SiC, and fiber was assessed in three Norwegian SiC plants together with information on potential determinants of exposure. Mixed-effect models were constructed with natural log-transformed exposure as the dependent variable.
The exposure assessment resulted in about 700 measurements of each of the sampled agents. Geometric mean (GM) exposure for total dust, respirable dust, fibers, and SiC for all workers was 1.6mg m(-3) [geometric standard deviation (GSD) = 3.2], 0.30mg m(-3) (GSD = 2.5), 0.033 fibers cm(-3) (GSD = 5.2), and 0.069mg m(-3) (GSD = 3.1), respectively. Due to a large portion of quartz and cristobalite measurements below the limit of detection in the processing and maintenance departments (>58%), GM for all workers was not calculated. Work in the furnace department was associated with the highest exposure to fibers, quartz, and cristobalite, while work in the processing department was associated with the highest total dust, respirable dust, and SiC exposure. Job group was a strong determinant of exposure for all agents, explaining 43-82% of the between-worker variance. Determinants associated with increased exposure in the furnace department were location of the sorting area inside the furnace hall, cleaning tasks, building and filling furnaces, and manual sorting. Filling and changing pallet boxes were important tasks related to increased exposure to total dust, respirable dust, and SiC in the processing department. For maintenance workers, increased exposure to fibers was associated with maintenance work in the furnace department and increased exposure to SiC was related to maintenance work in the processing department.
Job group was a strong determinant of exposure for all agents. Several tasks were associated with increased exposure, indicating possibilities for exposure control measures. Recommendations for exposure reduction based on this study are (i) to separate the sorting area from the furnace hall, (ii) minimize manual work on furnaces and in the sorting process, (iii) use remote controlled sanders/grinders with ventilated cabins, (iv) use closed systems for filling pallet boxes, and (v) improve cleaning procedures by using methods that minimize dust generation.
本研究旨在确定挪威碳化硅（SiC）行业粉尘暴露的重要决定因素，并提出可能的控制措施。
在挪威的三家SiC工厂对总粉尘、可吸入粉尘、石英、方石英、SiC和纤维的暴露情况进行了评估，并收集了有关暴露潜在决定因素的信息。以自然对数转换后的暴露量作为因变量构建混合效应模型。
暴露评估对每种采样物质进行了约700次测量。所有工人的总粉尘、可吸入粉尘、纤维和SiC的几何平均（GM）暴露量分别为1.6mg/m³[几何标准差（GSD）=3.2]、0.30mg/m³（GSD=2.5）、0.033根/立方厘米（GSD=5.2）和0.069mg/m³（GSD=3.1）。由于加工和维修部门中大部分石英和方石英的测量值低于检测限（>58%），因此未计算所有工人的GM值。炉窑部门的工作与纤维、石英和方石英的最高暴露相关，而加工部门的工作与总粉尘、可吸入粉尘和SiC的最高暴露相关。工种是所有物质暴露的一个重要决定因素，解释了工人之间43%-82%的差异。与炉窑部门暴露增加相关的决定因素包括炉窑大厅内分选区域的位置、清洁任务、建造和填充炉窑以及人工分选。填充和更换托盘箱是与加工部门总粉尘、可吸入粉尘和SiC暴露增加相关的重要任务。对于维修工人，纤维暴露增加与炉窑部门的维修工作有关，SiC暴露增加与加工部门的维修工作有关。
工种是所有物质暴露的一个重要决定因素。多项任务与暴露增加相关，这表明有采取暴露控制措施的可能性。基于本研究的降低暴露建议如下：（i）将分选区域与炉窑大厅分开；（ii）尽量减少炉窑作业和分选过程中的体力劳动；（iii）使用带通风舱的遥控砂光机/研磨机；（iv）使用封闭系统填充托盘箱；（v）通过采用减少粉尘产生的方法改进清洁程序。
