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Silicosis: Respirable Cristobalite Exposures

Respirable cristobalite: Geometric mean exposures and percent exceeding designated occupational exposure limits, MSHA and OSHA samples, 1979-2003
Table showing Respirable cristobalite: Geometric mean exposures and percent exceeding designated occupational exposure limits, MSHA and OSHA samples, 1979-2003

- indicates incalculable field.PEL - permissible exposure limitREL - recommended exposure limitGM

Note:  Before March 1, 1989 and after March 22, 1993, the OSHA PEL is [(5 mg/m3) / (% cristobalite + 2)], for respirable dust containing at least 1 percent cristobalite. From March 1, 1989 to March 22, 1993, the OSHA PEL was 0.05 mg/m3 for respirable cristobali

Source:  MSHA metal/nonmetal mine data. OSHA Integrated Management Information System.

Reference Number: 2007T03-21

Date Posted: June 2008

Archived Versions:
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