Page:NIOSH Manual of Analytical Methods - 5503.pdf/2

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POLYCHLOROBIPHENYLS: METHOD 5503, Issue 2, dated 15 August 1994 - Page 2 of 5 REAGENTS:

EQUIPMENT:

1. Hexane, pesticide quality. 2. Florisil, 30/48 mesh sieved from 30/60 mesh. After sieving, dry at 105 °C for 45 min. Mix the cooled Florisil with 3% (w/w) distilled water. 3. Nitrogen, purified. 4. Stock standard solution of the PCB in methanol or isooctane (commercially available).*

See SPECIAL PRECAUTIONS.

1. Sampler: 13-mm glass fiber filter without binders in a Swinnex cassette (Cat. No. SX 0001300, Millipore Corp.) followed by a glass tube, 7 cm long, 6-mm OD, 4-mm ID containing two sections of 30/48 mesh deactivated Florisil. The front section is preceded by glass wool and contains 100 mg and the backup section contains 50 mg; urethane foam between sections and behind the backup section. (SKC 226-39, Supelco ORBO-60, or equivalent) Join the cassette and Florisil tube with PVC tubing, 3/8" L x 9/32" OD x 5/32" ID, on the outlet of the cassette and with another piece of PVC tubing, 3/4" L x 5/16" OD x 3/16" ID, complete the union. 2. Personal sampling pump, 0.05 to 0.2 L/min, with flexible connecting tubing. 3. Tweezers. 4. Vials, glass, 4- and 7-mL, with aluminum or PTFE-lined caps 5. Gas chromatograph, electron capture detection ( 63Ni), integrator and column (page 5503-1). 6. Volumetric flasks, 10-mL and other convenient sizes for preparing standards. 7. Syringe, 10-µL.

SPECIAL PRECAUTIONS: Avoid prolonged or repeated contact of skin with PCB and prolonged or repeated breathing of the vapor [9-11].

SAMPLING: 1. 2. 3.

4.

Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the Florisil tube immediately before sampling. Connect Florisil tube to Swinnex cassette and attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.05 and 0.2 L/min for a total sample size of 1 to 50 L. NOTE: At low PCB concentrations, the sampler was found to be efficient when operated at flow rates up to 1 L/min, for 24 hours [4]. Under these conditions, the limit of detection was 0.02 µg/m 3. Transfer the glass fiber filters to 7-mL vials. Cap the Florisil tubes with plastic (not rubber) caps and pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the glass wool and 100-mg Florisil bed in the same 7-mL vial in which the filter was stored. Add 5.0 mL hexane. In a 4-mL vial, place the 50-mg Florisil bed including the two urethane plugs. Add 2.0 mL hexane. Allow to stand 20 min with occasional agitation. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94