National Institute for Occupational Safety and Health, NIOSH Manual of Analytical Methods… (1994)
“ Place 1 spatula full of dust (approximately 0.1 cm3; the size of a small pea) to be tested in a 15-mL clear plastic centrifuge tube. Add extraction solution up to the 2-mL mark. Cap the tube and shake vigorously. 2. Allow the tube to stand for 10 minutes, or longer, with occasional shaking. NOTE: Gently heating the tube in hot water will increase the sensitivity of the test. 3. Uncap the centrifuge tube and add deionized water to the 7-mL mark. Mix and allow the residue to settle. 4. Decant or pipet approximately 3 mL of the supernatant liquid into a second tube. ”
