Publication Date |
1977 |
Personal Author |
Dement, J. M.; Zumwalde, R. D. |
Page Count |
160 |
Abstract |
Bulk samples of talc were collected and personal air sampling was conducted in the mine and the mill. X-ray diffraction and optical or electron microscope analysis was conducted by NIOSH and two independent laboratories. All laboratories confirmed the presence of asbestiform tremolite and anthophyllite in the bulk talc samples at concentrations of 67 to 88 and 4 to 12 percent, respectively. Time weighted average (TWA) values for fiber and dust personal exposures for almost 30 job categories ranged from 1.7 to 9.8 fibers greater than 5 microns per cubic centimeter, and 0.25 to 2.96 milligrams per cubic meter, respectively. Free silica exposures were very low. Analysis of the impinger samples revealed excessive exposure to asbestos at almost every mine and mill operation. The authors conclude that excessive exposures to airborne fibers exist in both mine and mill. Recommendations include improved ventilation, upgraded equipment maintenance, and provision of respiratory protection to employees. |
Keywords |
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Source Agency |
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NTIS Subject Category |
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Corporate Authors |
National Inst. for Occupational Safety and Health, Cincinnati, OH. Div. of Surveillance, Hazard Evaluations and Field Studies. |
Supplemental Notes |
See also PB81-224719. Portions of this document are not fully legible. |
Document Type |
Technical Report |
Title Note |
Final rept., |
NTIS Issue Number |
198901 |