Page:NIOSH Manual of Analytical Methods - 1019.pdf/2

 1,1,2,2-TETRACHLOROETHANE: METHOD 1019, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4. 5. 6.

EQUIPMENT:

Carbon disulfide (CS 2), chromatographic quality.* 1,1,2,2-Tetrachloroethane, reagent grade.* DE stock solution, 50 mg/mL. Dilute 0.5 g 1,1,2,2-tetrachloroethane to 10 mL with CS 2. Nitrogen, purified. Hydrogen, prepurified. Air, filtered, compressed.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 7 cm long, 6-mm OD, 4mm ID, flame-sealed ends with plastic caps, containing two sections of 20/40 mesh activated petroleum-based 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. Tubes are commercially available (SKC 226-38, or equivalent). 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. Gas chromatograph, flame ionization detector, integrator, and column (see page 1019-1). 4. Vials, 2-mL, PTFE-lined caps. 5. Syringes, 10-µL, readable to 0.1 µL. 6. Volumetric flasks, 10-mL. 7. Pipet, TD, 1-mL.

SPECIAL PRECAUTIONS: 1,1,2,2-Tetrachloroethane is a powerful narcotic, liver poison, and suspected carcinogen, and can be absorbed through the skin [4-6]. Carbon disulfide is toxic and a serious fire and explosion hazard (flash point = -30 °C). Work with these substances 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. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 3 to 30 L. Cap the samplers. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the front and back sorbent sections of the sampler tube in separate vials. Discard the glass wool and foam plugs. Add 1.0 mL CS 2 to each vial. Cap each vial. Allow to stand 30 min with occasional agitation.

CALIBRATION AND QUALITY CONTROL: 8.

Calibrate daily with at least six working standards. a. Add known amounts of 1,1,2,2-tetrachloroethane to CS 2 in 10-mL volumetric flasks and dilute to the mark. Use serial dilutions as needed to obtain 1,1,2,2-tetrachloroethane concentrations in the range 0.01 to 1 mg/mL. b. Analyze with samples and blanks (steps 11 and 12). c. Prepare calibration graph (peak area vs. mg 1,1,2,2-tetrachloroethane).

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