Page:NIOSH Manual of Analytical Methods - 9000.pdf/2

 CHRYSOTILE ASBESTOS (BULK): METHOD 9000, Issue 2, dated 15 August 1994 - Page 2 of 6 REAGENTS: 1.

2. 3. 4.

EQUIPMENT:

Chrysotile*, available from: Analytical Reference Minerals, Measurements Research Branch, DPSE, NIOSH, 4676 Columbia Parkway, Cincinnati, OH 45226; or UICC Asbestos Reference Sample Set, UICC MRC Pneumoconiosis Unit Llandough Hospital, Penarth, Glamorgan, CF6 1XW, UK.2. 2-Propanol.* Desiccant. Glue or tape for securing Ag filters to XRD holders.



See SPECIAL PRECAUTIONS.

1. Vials, plastic (for bulk sample). 2. Freezer mill, liquid N 2-cooled, (Spex Model 6700 or equivalent), grinding vials (Spex 6701), extractor (Spex 6704). 3. Ultrasonic bath. 4. Sieve, 10-µm, for wet-sieving. 5. Filters, polycarbonate, 1.0-µm, 37-mm (Nuclepore or equivalent). 6. Filtration apparatus and side-arm vacuum flask with 25- and 37-mm filter holders. 7. Oven, drying, 110 °C. 8. Analytical balance, readable to 0.01 mg. 9. Beaker, Griffin, 50-mL, with watchglass cover. 10. Filters, silver membrane, 25-mm diameter, 0.45-µm pore size (Millipore Corp., Poretics Corp., or equivalent). 11. Desiccator. 12. Bottles, glass, 1-L, with ground glass stoppers. 13. Wash bottle, polyethylene. 14. Magnetic stirrer. 15. X-ray powder diffractometer with copper target x-ray tube and scintillation detector. 16. Reference specimen (mica, Arkansas stone or other stable standard) for data normalization. 17. Volumetric pipettes and flasks.

SPECIAL PRECAUTIONS: Asbestos, a human carcinogen, should be handled in a hood [4]. 2-Propanol is flammable.

SAMPLING: 1.

Place several grams of the dust to be analyzed in a plastic vial, seal the vial securely and ship in a padded carton.

SAMPLE PREPARATION: 2. 3.

4.

Place ca. 0.5 g of sample dust in a grinding vial and grind in a liquid nitrogen-cooled mill for 2 to 10 min. Wet sieve the ground dust using a 10-µm sieve and 2-propanol. Place the dust on the sieve and place the sieve directly in an ultrasonic bath or in a wide dish in the bath. Use enough 2-propanol to cover the dust (put water in the bath if a dish is used to contain the 2-propanol). Apply ultrasonic power to sieve the dust. NOTE: It may take some time to obtain several mg of dust. Heating of the 2-propanol is likely and cooling periods may be required. Recover the sieved sample dust from the 2-propanol by filtering the suspension through a non-fibrous filter (polycarbonate) or by driving off the 2-propanol on a hot plate. Dry the sieved sample in 110 °C oven for 4 h or more.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94