Page:NIOSH Manual of Analytical Methods - 5021.pdf/2

 o-TERPHENYL: METHOD 5021, Issue 2, dated 15 August 1994 - Page 2 of 3 EQUIPMENT:

REAGENTS: 1. 2. 3. 4.

5. 6. 7.

Carbon disulfide, chromatographic quality.* ortho-Terphenyl, reagent grade.* Hexane, chromatographic quality.* Calibration stock solution, 1 mg/mL. Dissolve an accurately weighed 100 mg o-terphenyl in hexane and dilute to 100 mL. Air, filtered, compressed. Nitrogen, purified. Hydrogen, prepurified.

1.

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



See SPECIAL PRECAUTIONS. 8. 9. 10.

Sampler: PTFE laminated membrane filters, 2.0-µm, 37-mm (Zefluor, Membrana Corp., Pleasonton, CA, or equivalent) backed by a gasket (37-mm OD, 32-mm ID) cut from a cellulose acetate support pad (available SKC, Inc. #225-23) in cassette filter holder. Personal sampling pump, 1 to 3 L/min, with flexible connecting tubing. Vials, scintillation, screw cap, 20-mL. Tweezers. Gas chromatograph, FID, integrator, and column (page 5021-1). Beakers, 50-mL. Centrifuge tubes, graduated, calibrated at 0.5 mL. Volumetric flasks, 10- and 100-mL. Pipets, 1.0 to 100-µL. Syringe, 10-µL, readable to 0.1 µL.

SPECIAL PRECAUTIONS: Exposure to terphenyls may cause eye, skin, and respiratory irritation [3]. Carbon disulfide presents a severe hazard owing to its toxic properties and fire and explosion potential (flash point = -30 °C). All work with this solvent should be performed in a fume hood. Hexane has a flash point = -22 °C.

SAMPLING: 1. 2. 3.

Calibrate each personal sampling pump with a representative sampler in line. Sample at an accurately known flow rate between 1 and 3 L/min for a total sample size of 2 to 30 L. Transfer the filter from the cassette within 1 h of sampling to a clean vial. Handle the filter only with clean tweezers.

SAMPLE PREPARATION: 4. 5. 6.

Remove filter from vial and place in 50-mL beaker. Rinse vial with 1 mL CS 2. Extract filter three times with 1-mL portions of CS 2. Transfer the extracts and vial rinsing to a graduated centrifuge tube. Gently evaporate the solution with a stream of nitrogen to a final volume of 0.5 mL.

CALIBRATION AND QUALITY CONTROL: 7.

Calibrate daily with at least six working standards over the range 0.002 to 0.5 mg o-terphenyl per sample. a. Add known amounts of calibration stock solution to CS 2 in 10-mL volumetric flasks and dilute to the mark. b. Analyze together with samples and blanks (steps 10 and 11). c. Prepare calibration graph (peak area vs. mg of o-terphenyl).

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