Résumé
<p><b>OBJECTIVE</b>The main purpose of this work was to give the evidence of reasonable and feasible dust control measures which will be taken in the future by analyzing the trend of dust concentration from 1991 to 2010 and identifying working faces with the severe dust contamination in one underground iron mine.</p><p><b>METHODS</b>The data was from routine monitoring between the years 1991 and 2010, which enclosed the total dust concentrations and silica contents. China National Standard of Occupational exposure limits for hazardous agents in the workplace used to judge whether the dust concentration exceeded the National Standard.</p><p><b>RESULTS</b>The general trend of total dust concentration from 1991 to 2010 was decreased, especially maximum and average levels. The highest exceeding rate was 43.16% in 1993 and the best years were 2009 and 2010, but the exceeding rates were still over 30%. The dust exposure levels varied with different work faces. The mining and supporting were the most severe dust pollution faces which the highest ultra exceeding rates were 51.61% and 51.48% and the maximum exceeding times were 64.6 and 16.4 respectively. The next was constructing face with 40.23% exceeding rate and 24.6 times more than standard.</p><p><b>CONCLUSION</b>The trend of total dust concentration from 1991 to 2010 was decreased, but the dust exceeding rate was still high. The strong measures should be taken to control the dust pollution in this iron mine, especially mining and supporting faces.</p>