Page:NIOSH Manual of Analytical Methods - 7029.pdf/2

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COPPER (dust and fume): METHOD 7029, Issue 2, dated 15 August 1994 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4.

5. 6. 7.

Nitric acid, conc. Hydrochloric acid, conc. Hydrochloric acid, 0.5 N. Add 41.5 mL conc. HCl to water, dilute to 1 L. Calibration stock solution, 1000 µg/mL. Commercially available, or dissolve 1.000 g Cu metal in minimum volume of (1:1) HNO 3. Dilute to 1 L with 0.5 N HCl. Distilled-deionized water. Air, filtered. Acetylene.

See SPECIAL PRECAUTIONS.

1. Sampler: cellulose ester membrane filter, 0.8-µm pore size, 37 mm-diameter; in cassette filter holder. 2. Personal sampling pump, 1 to 3 L/min, with flexible connecting tubing. 3. Atomic absorption spectrophotometer with an air-acetylene burner head and copper hollow cathode lamp and two-stage regulators for air and acetylene. 4. Beakers, Phillips, 125-mL, or Griffin, 50-mL, with watchglass covers.* 5. Volumetric flasks, 25-mL.* 6. Assorted volumetric pipets, as needed.* 7. Hotplate, surface temperature 140 °C and 400 °C. 8. Equipment for fume/dust separation step: a. cellulose ester membrane filters, 47-mm, 0.3-µm pore size (Millipore PHWP or equivalent); b. cellulose ester membrane filter, 47-mm, 5-µm pore size (Millipore SMWP or equivalent); c. filtration apparatus (Gelman No. 1107 or equivalent).

Clean all glassware with conc. nitric acid and rinse thoroughly with distilled or deionized water before use.

SPECIAL PRECAUTIONS: Perform all acid digestions in a fume hood.

SAMPLING: 1. 2.

Calibrate each personal sampling pump with a representative sampler in line. Sample at an accurately known flow rate between 1 and 3 L/min for a sample size of 50 to 1500 L. Do not exceed a total filter loading of ca. 2 mg total dust.

SAMPLE PREPARATION:

3.

NOTE: The following sample preparation gave quantitative recovery (see EVALUATION OF METHOD). Other quantitative ashing techniques (e.g., HNO 3-HClO 4 [Method 7300]) may be useful alternatives, especially if several metals are to be determined on a single filter. Proceed to step 4 if fume/dust separation is not desired. For fume/dust separation: a. Using forceps, prewet a 47-mm, 0.3-µm pore size cellulose ester membrane filter by placing it on the surface of distilled water. Remove the filter, tap off excess water, and mount it on the filtration unit. b. Transfer the sample filter from the cassette filter holder to the filtration unit, placing it concentrically on top of the 47-mm filter with the fume deposit up. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94