Page:NIOSH Manual of Analytical Methods - 5517.pdf/2

 POLYCHLOROBENZENES: METHOD 5517, Issue 2, dated 15 August 1994 - Page 2 of 5 REAGENTS: 1. 2. 3. 4. 5.

6.

EQUIPMENT:

Hexane, distilled in glass.* Pentachlorobenzene, 98%.* 1,2,4,5-Tetrachlorobenzene, 98%.* 1,2,4-Trichlorobenzene, 99%.* Calibration stock solution, 100 mg/mL. Dilute accurately weighed 500-mg portions of each analyte to 5 mL with hexane. Store in airtight container. Stock solution is stable indefinitely. Amberlite, XAD-2, 20/50 mesh. Cleanse by Soxhlet extraction for 4 h with 4:1 (v/v) acetone/methanol, 4 h with hexane, and drying overnight at 70 to 100 °C under vacuum. NOTE: During method evaluation, the capacity of cleansed bulk Amberlite XAD-2 was much higher than that of Amberlite XAD-2 obtained from some commercially available sorbent tubes.

1.

2. 3.

See SPECIAL PRECAUTIONS. 4. 5. 6. 7. 8. 9. 10.

SAMPLING: 1.

2. 3. 4.

Two-stage sampler: a. Filter: PTFE filter, 13-mm, 5-µm pore size, unlaminated (Millipore, SKC, Inc., or equivalent) in stainless steel holder, Swinny-type (Millipore, SKC, or equivalent). b. Sorbent tube: glass, 7 cm long, 6.4-mm OD, 4-mm ID, flame sealed with plastic caps, containing two sections of cleansed Amberlite XAD-2 (front = 100 mg; back = 50 mg), separated and held in place by 4-mm silanized glass wool plugs. Tubes are commercially available (SKC, Inc. or equivalent). c. Assembly: To outlet (male luer tip) of filter holder, attach a short (ca. 1.5") piece of PTFE tubing, 6-mm OD, 4mm ID. Attach sorbent tube to PTFE tube on filter holder with a short piece of flexible tubing. Seal inlet of filter holder and outlet of sorbent tube with PTFE tape and plastic caps. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. Gas chromatograph, 63Ni electron capture detector, integrator, and column (see page 5517-1). Vials, 5-mL, PTFE-lined caps. Syringe, 10-µL, readable to 0.1 µL. Volumetric flasks, 5-mL, and convenient sizes for making dilutions. Pipets, 2-mL, and convenient sizes for making dilutions. Ultrasonic bath. Balance, readable to 1 mg. PTFE tape.

SPECIAL PRECAUTIONS: Hexane (flash point = -22 °C) is highly flammable. Prepare samples and standards in well-ventilated hood.

Calibrate each personal sampling pump Chlorinated benzenes may irritate skin, eyes, and with a representative sampler in line. NOTE: The filter stage permits measurement of exposures to polychlorobenzene aerosols. If it is known that such exposure is not likely, the filter may be omitted. Remove caps from sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for total sample size of 3 to 12 L. Separate filter from sorbent tube and seal both with PTFE tape and caps. Pack securely for shipment.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94