Selection and characterization of fibrous and nonfibrous amphiboles for analytical methods development.
Haartz-JC; Lange-BA; Draftz-RG; Scholl-RF
Workshop on Asbestos: Definitions and Measurement Methods. Washington, DC: National Bureau of Standards, U.S. Department of Commerce, NBS Special Publication No. 506, 1978 Nov; :295-312
Mineral samples were characterized to determine their suitability for use as reference materials in the development of new analytical methods to determine workplace contaminants. Fifty fibrous and prismatic (nonfibrous) amphibole (1332214) samples were collected from various sources. Only 38 were carried through the preliminary characterization steps before 11 were chosen for closer study. Specimens that required beneficiation to liberate pure minerals were separated by hand. Fibrous amphiboles were ground in a fiber mill for size reductions. Prismatic amphiboles were ground using a jet mill. Fibrous and prismatic tremolite (14567738) samples with a mean particle length or diameter of less than 3.0 micrometers were studied by chemical analysis, X-ray diffraction, and differential thermal analysis. All the samples were determined to be tremolite according to the chemical analysis. Samples as small as 20 micrograms could be quantified using X-ray diffraction. Peak intensities were determined. The peak ratios for prismatic tremolite were larger than for samples of fibrous tremolite. Differential thermal analysis gave good calibration curves but was not sensitive enough to detect microgram quantities of tremolite. The authors conclude that X-ray diffraction analysis has potential applications for analysis of workplace contaminants.
Air-sampling; Dusts; Asbestos-dusts; Air-contamination; Chemical-analysis; Airborne-dusts; Fibrous-dusts; Air-monitoring; Silica-dusts; Mineral-dusts; Analytical-methods; X-ray-diffraction-analysis; Airborne-contaminants; Chemical-processing; Mineral-processing
1332-21-4; 14567-73-8; 60649-53-8; 17499-08-0
Workshop on Asbestos: Definitions and Measurement Methods, National Bureau of Standards, U.S. Department of Commerce, NBS Special Publication No. 506