Page:NIOSH Manual of Analytical Methods - 2505.pdf/2

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FURFURYL ALCOHOL: METHOD 2505, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS:

EQUIPMENT: 1.

1. 2. 3. 4.

5. 6. 7.

Furfuryl alcohol* (purify as in APPENDIX). Acetone, distilled in glass. Benzene,* distilled in glass. DE stock solution, 0.1 mg/µL. Dilute 1.0 g furfuryl alcohol to 10 mL with benzene. NOTE: Acetone may be substituted for benzene if desorption efficiency is adequate. Nitrogen, purified. Hydrogen, prepurified. Air, filtered.

See Special Precautions.

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

Sampler: glass tube, flame-sealed with plastic caps, 8.5 cm long, 6-mm OD, 4-mm ID; two sections of 50/80 mesh pre-extracted Porapak Q (front = 150 mg; back = 75 mg) separated by a 2-mm section of urethane foam and held in place with plugs of silanized glass wool. Tubes are commercially available. Personal sampling pump, 0.01 to 0.05 L/min, with flexible connecting tubing. Gas chromatograph, flame ionization detector, integrator and column (page 2505-1). Vials, glass, 2-mL, PTFE-lined crimp caps. Syringes, 10- to 50-µL, readable to 0.1 µL. Volumetric flasks, 10-mL and other convenient sizes. Pipets, TD, 1.0-mL and other convenient sizes.

SPECIAL PRECAUTIONS: Furfuryl alcohol is toxic and reacts violently with acids [5]. Benzene SAMPLING: is a suspected human carcinogen [5]. Perform all work with this solvent in a hood. 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 0.05 L/min for a total sample size of 3 to 25 L. 4. Cap the samplers and pack securely for shipment. SAMPLE PREPARATION: 5. Place the front and back sorbent sections of the sampler tube in separate vials. Discard the glass wool and foam plugs. 6. Add 1.0 mL acetone to each vial. Cap each vial. 7. Allow to stand 15 min with occasional agitation. CALIBRATION AND QUALITY CONTROL: 8. Calibrate daily with at least six working standards over the range 0.01 to 3.6 mg furfuryl alcohol per sample. a. Add known amounts of pure furfuryl alcohol to acetone or benzene in 10-mL volumetric flasks and dilute to the mark. Use serial dilutions to prepare the lower concentrations. b. Analyze together with samples and blanks (steps 11 and 12). c. Prepare calibration graph (peak area vs. mg furfuryl alcohol). 9. Determine desorption efficiency (DE) at least once for each lot of Porapak Q used for sampling in the calibration range (step 8). Prepare three tubes at each of five levels plus three media blanks. a. Remove and discard back sorbent section of a media blank sampler. b. Inject a known amount of DE stock solution or a serial dilution thereof, directly onto front sorbent section with a microliter syringe. c. Cap the tube. Allow to stand overnight. d. Desorb (steps 5 through 7) and analyze together with working standards (steps 11 and 12). e. Prepare a graph of DE vs. mg furfuryl alcohol recovered. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94