Page:NIOSH Manual of Analytical Methods - 1013.pdf/2

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PROPYLENE DICHLORIDE: METHOD 1013, Issue 2, dated 15 August 1994 - Page 2 of 4

REAGENTS:

EQUIPMENT:

1. Acetone, distilled in glass.* 2. Cyclohexane, distilled in glass.* 3. Eluent: 15% (v/v) acetone in cyclohexane. 4. Propylene dichloride, reagent grade.* 5. Nitrogen, high purity, for GC carrier gas. 6. Hydrogen, prepurified, for Hall detector. 7. Electrolyte solution for Hall detector: 2-propanol and distilled, deionized water, 50% (v/v). 8. Calibration stock solution, 34.7 mg/mL. Dilute 3.00 mL (3.47 g) 1,2-dichloropropane to 100 mL with eluent. Stable indefinitely at room temperature in airtight container.

  • 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 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 0.2 L/min airflow must be less than 3.4 kPa. Tubes are commercially available (SKC No. 226-65 or equivalent). 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. PTFE tape. 4. Gas chromatograph with Hall electrolytic conductivity detector and column (page 1013-1). 5. Vials, 1-mL, with PTFE-lined silicone rubber septa and serum caps.† 6. Syringes, 10-mL and other convenient sizes for making dilutions. 7. Pipets, 1-mL and other convenient sizes for making dilutions.† 8. Volumetric flasks, 10- and 100-mL.† 9. Ultrasonic bath. Clean thoroughly and rinse with, in order, 50% (v/v) HNO3, distilled water, acetone, and cyclohexane.

SPECIAL PRECAUTIONS: Propylene dichloride vapor is a narcotic and an eye irritant [3]. Acetone and cyclohexane are extremely flammable. Work with these in a fume hood. SAMPLING: 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Break the ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. 3. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 0.1 to 3.5 L. 4. Cap the samplers with PTFE tape. Pack securely for shipment. Store samplers in the dark. 5. Refrigerate the samplers in an airtight container upon receipt. SAMPLE PREPARATION: 6. Bring the samplers to room temperature before uncapping to prevent moisture condensation on the sorbent. 7. Place the front and back sorbent sections of the sampler tube in separate vials. Place the glass wool plug with the front sorbent section and the foam plugs with the back sorbent section. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition