Page:NIOSH Manual of Analytical Methods - 1600.pdf/2

 CARBON DISULFIDE: METHOD 1600, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3.

4. 5. 6. 7.

EQUIPMENT:

Carbon disulfide, chromatographic quality.* Toluene, chromatographic quality. Calibration stock solution, 0.0253 mg/µL. Dilute 0.253 g CS 2 (0.200 mL at 20 °C) to 10 mL with toluene. Prepare in duplicate. Oxygen, purified. Nitrogen or helium, purified. Hydrogen, prepurified. Air, filtered compressed.



See SPECIAL PRECAUTIONS.

1. Sampler: a. Drying tube: glass tube, 7 cm long, 6-mm OD, 4-mm ID; single 270-mg section of granular anhydrous sodium sulfate between two silylated glass wool plugs. This removes moisture equivalent to 6 L of air at 100% RH and 22 °C. b. Sorbent tube: glass tube, 7 cm long, 6-mm OD, with flame-sealed ends and plastic caps, containing two sections of activated (600 °C) coconut shell charcoal (front = 100 mg; back = 50 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. Available commercially. 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. PTFE tubing, 5-mm ID. 4. Refrigerant, bagged (0 °C). 5. Gas chromatograph, FPD with sulfur filter, integrator and column (see page 1600-1). NOTE: A valve to vent the solvent peak when it elutes from the column is useful to protect the detector. 6. Vials, glass, 25-mL, PTFE-lined caps. 7. Volumetric flasks, 10-mL. 8. Syringe, 10-µL, readable to 0.1 µL. 9. Delivery pipets, 1- to 100-µL and 1-mL, with pipet bulb.

SPECIAL PRECAUTIONS: Carbon disulfide is toxic and an acute fire and explosion hazard (flash point = -30 °C) [3,7]; work with it only in a hood.

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. Connect the drying tube to the front section of the charcoal tube with a 20-mm section of PTFE tubing. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 2 to 25 L. NOTE: Samples may be taken up to 1 L/min if ambient humidity is low [3,4]. Keep the drying tube connected to the charcoal tube during shipping. Refrigerate (0 °C) to prevent CS 2 migration to the back section. Cap the open ends. Pack securely for shipment. NOTE: Store samples away from any source of CS 2 to avoid contamination.

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