Page:NIOSH Manual of Analytical Methods - 1006.pdf/2

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FLUOROTRICHLOROMETHANE: METHOD 1006, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1.

2. 3. 4. 5.

EQUIPMENT:

Eluent: carbon disulfide,* chromatographic quality, containing 0.1% (v/v) nonane as internal standard. Fluorotrichloromethane, 99%. Nitrogen, purified. Hydrogen, prepurified. Air, filtered, compressed.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 10 cm long, 8-mm OD, 6-mm ID, flame-sealed ends with plastic caps, containing two sections of 20/40 mesh activated (600 °C) coconut shell charcoal (front = 400 mg; back = 200 mg) separated by a 2-mm urethane foam plug. A silylated glass wool plug precedes the front section and a 3-mm urethane foam plug follows the back section. Pressure drop across the tube at 1 L/min airflow must be less than 3.4 kPa. Tubes are commercially available. 2. Personal sampling pump, 0.01 to 0.05 L/min, with flexible connecting tubing. 3. Refrigerant, bagged. 4. Gas chromatograph, flame ionization detector, integrator, and column (see page 1006-1). 5. Vials, glass, 10-mL, PTFE-lined septum crimp caps. 6. Syringes, 10-µL, readable to 0.1 µL. 7. Syringes, gas-tight, 10-µL to 10-mL. 8. Syringe needle, 22-gauge. 9. Volumetric flasks, 10-mL. 10. Pipet, TD, 5-mL. 11. Balance, 0.1-mg sensitivity.

SPECIAL PRECAUTIONS: Carbon disulfide is toxic and a serious fire and explosion hazard (flash point = -30 °C). Work with it only in a hood and away from spark sources.

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.01 and 0.05 L/min for a total sample size of 0.3 to 7 L. Cap the sampler. Pack securely for shipment in an insulated container with bagged refrigerant.

SAMPLE PREPARATION: 5. 6. 7. 8.

Place the front and back sorbent sections of the sampler in separate vials. Discard the glass wool and foam plugs. Seal each vial with a septum and crimp seal. Insert a syringe needle through the septum to serve as a vent. Add 5.0 mL eluent to each vial with a syringe. Remove the vent from the septum. Allow to stand 30 min with occasional agitation.

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