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ASBESTOS by TEM: METHOD 7402, Issue 2, dated 15 August 1994 - Page 2 of 7 <br /> REAGENTS: <br /> 1 1: Acetone. (See SPECIAL PRECAUTIONS.) <br /> i <br /> EQUIPMENT: <br /> 1. Sampler: field monitor, 25-mm, three-piece cassette with ca. 50-mm electrically-conductive <br /> embrahe filter, 0.45-to 1.2-Nm pore size, and backup pad. <br /> extension cowl, cellulose ester m <br /> NOTE 1: Analyze representative filters for fiber background before use. Discard the filter lot if <br /> mean count is >5 fibers/100 fields. These are defined as laboratory blanks. <br /> NOTE 2: Use an electrically-conductive extension cowl to reduce electrostatic effects on fiber <br /> sampling and during sample shipment. Ground the cowl when possible during <br /> sampling. <br /> ended for personal sampling_ 0.45-}gym filters are <br /> NOTE 3: 0.8-Nm pore size filters are recomm <br /> recommended for sampling when performing TEM analysis on the samples because the <br /> particles deposit closer to the filter surface. However,the higher pressure drop through <br /> these filters normally preclude their use with personal sampling pumps_ . <br /> connecting <br /> tubing. <br /> conn 9 <br /> with flexible 9 <br /> 2. Personal sampling pump, 0.5 to 16 Umin, wtt <br /> 3. Microscope, transmission electron, operated at ca. 100 kV, with electron diffraction and <br /> energy-dispersive X-ray capabilities, and having a fluorescent screen with inscribed or overlaid <br /> calibrated scale (Step 15). <br /> NOTE: The scale is most efficient if it consists of a series of lines inscribed on the screen or partial <br /> circles every 2 cm distant from the center. <br /> 4. Diffraction grating replica with known number of lines/mm. <br /> 5. Slides, glass, pre-cleaned, 25- x 75-mm. <br /> ,I 6. Knife, surgical steel, curved-blade. <br /> 7. Tweezers_ <br /> 8. Grids, 200-mesh TEM copper, (optional: carbon-coated). <br /> 9. Petri dishes, 15-mm depth. The top and bottom of the petri dish must fit snugly together. To assure <br /> a tight fit, grind the top and bottom pieces together with an abrasive such as carborundum to <br /> produce a ground-glass contact surface. <br /> 10. Foam, clean polyurethane, spongy, 12-mm thick. <br /> 11. Filters, Whatman No. 1 qualitative paper, or equivalent, or lens paper. <br /> 12. Vacuum evaporator. <br /> 13. Cork borer, (about 8-mm). <br /> 14_ Pen, waterproof, marking_ <br /> 15. Reinforcement, page, gummed. <br /> 16. Asbestos standard bulk materials for reference;e.g.SRM#1866,available from the National Institute <br /> of Standards and Technology. <br /> 17. Carbon rods, sharpened to 1 mm x 8 mm. <br /> ith Walton-Beckett graticule (see method 7400). <br /> 18. Microscope, light, phase contrast(PCM), w <br /> 19. Grounding wire, 22-gauge, multi-strand. <br /> 20. Tape, shrink- or adhesive-. <br /> SPECIAL PRECAUTIONS: Acetone is extremely flammable(flash point=0°F). Take precautions not <br /> to ignite it. Heating of acetone must be <br /> done in a fume hood using a flameless, spark-free heat source. <br /> Asbestos is a confirmed human carcinogen. Handle only in a well-ventilated fume hood. <br /> NIOSH Manual of Analytical Methods(NMAM),Fourth Edition,8/15194 <br />