Page:NIOSH Manual of Analytical Methods - 3509.pdf/2

 AMINOETHANOL COMPOUNDS II: METHOD 3509, Issue 2, dated 15 August 1994 - Page 2 of 5 REAGENTS: 1.

2. 3. 4. 5. 6. 7.

8.

EQUIPMENT:

Hexanesulfonic acid (HSA), 2 m M (diluted from 0.1 M solution obtained from Dionex Corp.). Acetonitrile, reagent grade. Ethanolamine*, high purity. Diethanolamine*, high purity. Triethanolamine*, high purity. Water, distilled. Regenerant for IC suppressor. For fiber suppressor use 40 m M tetramethylammonium hydroxide (TMAOH) at 2 mL/min. For cation micromembrane suppressor use 2 m M TMAOH at 4 mL/min. Prepare fresh weekly and protect from atmospheric CO 2 (which can lead to high background). Calibration stock solution, 1 µg/µL. Weigh 0.10 g of each amine into 100-mL volumetric flask and dilute to mark with 2 m M hexanesulfonic acid. Store in a polyethylene bottle.

1. Sampler: midget impinger containing 15 mL of 2 mM HSA. 2. Personal sampling pump, 0.5 to 1 L/min, with flexible connecting tubing and glass wool trap. 3. Ion chromatograph, with ion-pairing guard and separator columns, cation suppressor (fiber suppressor or micromembrane suppressor), integrator and strip chart recorder (page 3509-1). 4. Marker, China. 5. Vials, scintillation, plastic, 20-mL, for shipping and storage of samples. 6. Syringes, 10-mL, polypropylene, with luer tip. 7. Filters, luer tip, with membrane filter, 13- or 25-mm, 0.45-µm pore size. 8. Micropipets (or microliter syringes), 1- to 500-µL. 9. Flasks, volumetric, 50-, and 100-mL. 10. Bottles, polyethylene, 100-mL. 11. Pipet, 15-mL.

See SPECIAL PRECAUTIONS.

SPECIAL PRECAUTIONS: Ethanolamines can cause skin and eye irritation [4]. Usual laboratory safety procedures should be exercised.

SAMPLING: 1. 2. 3. 4. 5. 6.

Calibrate each personal sampling pump with a representative sampler in line. Fill the impinger with 15 mL of 2 m M HSA. Mark the initial liquid level. Attach impinger to sampling pump with flexible tubing. Insert a glass wool trap between the impinger and sampling pump to prevent splashover. Sample at an accurately known flow rate between 0.5 and 1 L/min for a total sample size of 5 to 300 L. Fill the sample solution in the impinger to the 15-mL mark with distilled water. Transfer each impinger solution to a vial for shipment. Pack securely to avoid spillage during transit.

CALIBRATION AND QUALITY CONTROL: 7.

Calibrate daily with at least six working standards over the range of interest. a. Add known aliquots of calibration stock solution to 50-mL volumetric flasks and dilute to the mark with eluent. b. Store working standards in tightly-capped polyethylene bottles (glass may introduce sodium ions, a chromatographic interference). Prepare fresh weekly. c. Analyze working standards together with samples and blanks (steps 8 through 11). d. Prepare a calibration graph for each analyte (peak height vs. µg analyte).

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