Page:NIOSH Manual of Analytical Methods - 6005.pdf/2

This page needs to be proofread.

IODINE: METHOD 6005, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4. 5. 6. 7.

8.

EQUIPMENT:

Deionized, filtered water with specific conductance ≤10 µS/cm. Sodium carbonate (Na 2CO 3), reagent grade. Potassium iodide (KI), reagent grade. Iodine (I 2), reagent grade.* Toluene, distilled in glass. Eluent: 10 m M Na 2CO 3. Dissolve 4.240 g Na 2CO 3 in 4 L filtered, deionized water. Calibration stock solution, 1000 µg/mL of I ¯. Dissolve 0.1308 g KI in filtered, deionized water to make 100 mL solution. Desorption Efficiency (DE) stock solution, 50 µg/µL. Dissolve 500 mg I 2 in toluene to make 10 mL solution.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 7 cm long, 6-mm OD, 4mm ID, flame-sealed ends and plastic caps, containing two sections of 20/40 mesh alkali-treated charcoal (Barnebey-Cheney Type 580-19) (front = 100 mg; back = 50 mg) separated by 2-mm urethane foam plug. A glass wool plug and metal retaining spring precede the front section and a 3-mm foam plug follows the back section. Pressure drop ≤2.1 kPa across the tube at 1.2 L/min airflow. Tubes are commercially available (SKC No. 226-67, SKC, Inc., Eighty-Four, PA, or equivalent). 2. Personal sampling pump, 0.5 to 1 L/min, with flexible connecting tubing. 3. Ion chromatograph (IC), anion separator and guard columns, anion suppressor (page 6005-1), conductivity detector, integrator (optional) and strip chart recorder. 4. File, triangular. 5. Ultrasonic bath. 6. Vials, 20-mL, glass, with PTFE-lined screw caps. 7. Syringes, 3-mL, polyethylene with luer tip. 8. Filters, luer tip, with PTFE filter, 13-mm diameter, 5-µm pore size. 9. Volumetric flasks, 10-, 50-, and 100-mL. 10. Bottles, polyethylene, 100-mL. 11. Pipets, 0.05- to 3-mL. 12. Syringe, 5-µL, readable to 0.1 µL.

SPECIAL PRECAUTIONS: Iodine is a severe irritant to the eyes and respiratory system and, to a lesser extent, the skin [4]. SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Break ends of sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.5 and 1.0 L/min for a total sample size of 15 to 225 L. Cap samplers. Pack securely for shipment. NOTE: Refrigerate samples if stored longer than 7 days.

SAMPLE PREPARATION: 5. 6. 7. 8. 9.

Allow refrigerated samples to equilibrate at room temperature. Score sampler with a file in front of primary sorbent section. Break sampler at score line. Transfer front sorbent section with glass wool plug to vial. Place back sorbent section with foam plugs in separate vial. Add 3.0 mL eluent to each vial. Cap immediately. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94