Page:NIOSH Manual of Analytical Methods - 2008.pdf/2

 CHLOROACETIC ACID: METHOD 2008, Issue 2, dated 15 August 1994 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4. 5.

Water, filtered, deionized. Specific conductance ≤10 µS/cm. Sodium bicarbonate (NaHCO 3), reagent grade. Chloroacetic acid, ≥99%.* Eluent: 1.5 m M NaHCO 3. Dissolve 0.504 g NaHCO 3 in 4 L filtered, deionized water. Calibration stock solution, 1000 µg/mL. Dissolve 100 mg chloroacetic acid in 100 mL filtered, deionized water.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 7 cm long, 6-mm OD, 4-mm ID, with plastic caps, containing two sections of 20/40 mesh silica gel (front = 100 mg; back = 50 mg) contained and separated by three silanized glass wool plugs. Pressure drop across the tube at 0.2 L/min is ca. 0.6 kPa (2.6 in. H 2O). Tubes are commercially available (SKC, Inc. 226-47-01, or equivalent). NOTE: Chloroacetic acid is irreversibly adsorbed on urethane plugs. Use sorbent tubes with glass wool plugs. 2. Personal sampling pump, 0.05 to 0.2 L/min, with flexible connecting tubing. 3. Ion chromatograph (IC), anion separator and guard column, anion suppressor (page 2008-1), conductivity detector, integrator, and strip chart recorder. 4. Ultrasonic bath. 5. Vials, 20-mL, glass, with aluminum-lined plastic screw caps. 6. Syringes, 3-mL, polyethylene with luer tip. 7. Filter holder, luer tip, 13-mm, with PTFE filter, 5-µm pore size, or PTFE syringe filter. 8. Pipets, 10-µL to 2-mL. 9. Flasks, volumetric, 10- and 100-mL.

SPECIAL PRECAUTIONS: Chloroacetic acid is irritating to skin and mucous membranes [4]. Work with the concentrated material only in a hood.

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 0.05 to 0.2 L/min for a total sample size of 1 to 100 L. Cap the samplers. Pack securely for shipment. NOTE: Store samples in the dark. Refrigerate samples if stored longer than 7 days.

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

Allow refrigerated samples to equilibrate to room temperature. Transfer front sorbent section with front glass wool plug to vial. Place back sorbent section and other two glass wool plugs in separate vial. Add 2.0 mL deionized water to each vial. Cap immediately. Agitate vials in ultrasonic bath for 30 min at room temperature. Draw sample extract through 13-mm PTFE filter with 3-mL syringe.

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