Metal and non-metal miners' exposure to crystalline silica, 1998-2002.
BACKGROUND
Crystalline silica is well known to cause silicosis and other diseases. Exposure is common in the mining industry and consequently, the US Mine Safety and Health Administration (MSHA) evaluates miners exposure to silica to determine compliance with its exposure limit.


METHODS
MSHA exposure measurements were obtained for the 5-year period from 1998 to 2002 and average exposure was calculated classified by occupation and by mine. Evaluation criteria were whether average values exceeded MSHA's permissible exposure limit or the limit recommended by the National Institute for Occupational Safety and Health (NIOSH), whether there was a risk of exposure to freshly fractured silica, and whether there was a risk of a high rate of exposure to silica.


RESULTS
Miners in certain jobs are exposed to silica above permissible and recommended exposure limits. Some miners may also be exposed at a high rate or to freshly fractured silica.


CONCLUSIONS
Known dust control methods should be implemented and regular medical surveillance should be provided.
Weeks
James L
JL
Advanced Technologies & Laboratories International, Germantown, Maryland 20854, USA. jweeks@atlintl.com
Rose
Cecile
C
D000395:Air Pollutants, Occupational / Q000592:standards*; D000704:Analysis of Variance; D004391:Dust / Q000032:analysis; D004784:Environmental Monitoring / Q000592:standards / Q000706:statistics & numerical data*; D006801:Humans; D019570:Inhalation Exposure / Q000706:statistics & numerical data*; D008452:Maximum Allowable Concentration; D008906:Mining; D009314:National Institute for Occupational Safety and Health, U.S. / Q000592:standards / Q000706:statistics & numerical data; D016273:Occupational Exposure / Q000592:standards / Q000706:statistics & numerical data*; D016272:Occupational Health; D012189:Retrospective Studies; D012307:Risk Factors; D012822:Silicon Dioxide / Q000592:standards; D014481:United States
D000395:Air Pollutants, Occupational; D004391:Dust; D012822:Silicon Dioxide