美国长壁工作面的作业人员发现,目前尚难达到联邦政府制订的呼吸性粉尘标准.法斯特梅勒有限公司(FMI)及美国矿业局(USBM)也发现许多工作面存在着进风风流被严重污染的问题.目前,美国大部分工作面采用从下顺槽向上顺槽通风;风流经石门进入下顺槽,之后流入工作面,最后进入上顺槽回风巷.新鲜风流在进入工作面前就受到了污染.污染 Operators at the U.S. long-wall face found it hard to reach the federal government’s respirable dust standards at the moment. FMI and the U.S. Bureau of Mines (USBM) Most of the working face in the United States is ventilated upward and downward from the lower trough, the wind flows into the lower trough through the Shihmen, and then flows into the working face and finally enters the upper trough air return lane. In front of it was polluted