Page:NIOSH Manual of Analytical Methods - 5042.pdf/3

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BENZENE-SOLUBLE & TOTAL PARTICULATE (ASPHALT FUME): METHOD 5042, Issue 1, dated 15 January 1998 - Page 3 of 7

EQUIPMENT:

REAGENTS:

1. Benzene,* 5 ppm evaporation residue, e.g., 1. Sampler: 37-mm, 2-µm pore size, PTFE membrane filter laminated to PTFE (Zefluor, Aldrich Chemical Co. Cat. No. 27,070-9 or Pall Gelman Sciences, Cat. No. P5PJ037; equivalent. Supelco, Cat. No. 2-0043; SKC Cat. No. 2252. Acetone,* HPLC grade. 17-07; or equivalent hydrophobic filter), with 3. Hexane,* HPLC grade. cellulose support pad in a 37-mm cassette filter 4. Nitrogen,* purified and filtered. holder. 2. Personal sampling pump, 1 to 4 L/min, with flexible connecting tubing. 3. Balance, readable to 0.001 mg. 4. Static neutralizer, 210Po; replace according to manufacturer’s recommendations. 5. Environmental chamber or room for balance

  • See SPECIAL PRECAUTIONS.

(e.g., 20 ± 1 C, constant ± 5% relative humidity, and dust-free). 6. Weighing cups,* PTFE, 2-mL (Fisher Cat. No. 2006529, or equivalent), in a carrying rack. 7. Vacuum oven, equipped with in-line filter on vacuum release valve to remove dust. NOTE: Keep the interior of the vacuum oven dust-free for maximum sensitivity, reproducibility, and accuracy. 8. Forceps. 9. Test tubes,** glass, 13-mm x 100 mm, with PTFE-lined screw caps. 10. Pipet,** glass, volumetric, 3-mL, with bulb. 11. Pipet,** glass, Mohr, 2-mL, with bulb. 12. Clarification units, 6-mL PTFE-treated reservoir with 1-µm PTFE frit (Daigger and Company, Inc., Lincolnshire, IL, Cat. No. LID-2102-10US, or equivalent). 13. Pressure regulator, valve, tubing, in-line filter to remove dust and organics, with adapter for applying nitrogen pressure to the clarification unit. 14. Ultrasonic bath.

  • Rinse the weighing cups as follows.

a. Wash with acetone until all visible residue is removed. b. Rinse with hexane for several seconds. c. Air dry. d. Discard any weighing cups that are not visibly clean.

    • Rinse all glassware with acetone then hexane;

air dry. SPECIAL PRECAUTIONS: Benzene is a suspect carcinogen [4]. Asphalt fumes are considered a potential occupational carcinogen [4]. Benzene, hexane, and acetone are highly flammable. Prepare samples and standards in a well-ventilated hood and avoid skin contact. Use care when working with compressed gases.

PREPARATION OF FILTERS BEFORE SAMPLING:

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition