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VINYLIDENE CHLORIDE: METHOD 1015, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4.

5.

6. 7. 8.

EQUIPMENT:

Carbon disulfide (CS 2), chromatographic quality.* Vinylidene chloride, 99%.* Cyclohexane. Calibration stock solution, 10 mg/mL. Dissolve 0.1 g vinylidene chloride in CS 2 to make 10 mL solution. Prepare in duplicate. DE stock solution, 10 mg/mL. Dissolve 0.1 g vinylidene chloride in cyclohexane to make 10 mL solution. Prepare in duplicate. Nitrogen or helium, purified. Hydrogen, prepurified. Air, filtered.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 7-cm long, 6-mm OD, 4-mm ID, flame-sealed ends with 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. Tubes are commercially available. 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. Gas chromatograph, FID, integrator and column (page 1015-1). 4. Vials, glass, 2-mL, PTFE-lined caps. 5. Syringe, 10-µL, readable to 0.1 µL. 6. Volumetric flasks, 10-mL. 7. Pipets, volumetric, 10- to 100-µL, and 1.0-mL, with pipet bulb.

SPECIAL PRECAUTIONS: Vinylidene chloride is a suspect carcinogen [3]. Carbon disulfide and vinylidene chloride are toxic and severe fire and explosion hazards (flash point = -30 °C for CS 2 and -10 °C for vinylidene chloride). Work with both compounds only in a hood. Vinylidene chloride polymerizes above 0 °C, especially in the presence of oxygen or catalysts; explosive reaction products may result [4].

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 2.5 to 7 L. Cap the samplers. Pack securely for shipment. NOTE: Refrigerated shipment will decrease migration of vinylidene chloride to back sorbent section.

SAMPLE PREPARATION: 5. 6. 7.

Allow samples to equilibrate to room temperature before uncapping. Place the front and back sorbent sections of the sampler tube in separate vials. Add 1.0 mL CS 2 to each vial. Cap vial immediately. Allow to stand 30 min with occasional agitation.

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

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