Page:NIOSH Manual of Analytical Methods - 2523.pdf/2

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1,3-CYCLOPENTADIENE: METHOD 2523, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1.

2.

3. 4. 5. 6.

7. 8. 9.

EQUIPMENT:

Analyte: 5-norbornene-2,3-dicarboxylic anhydride (Eastman Chemicals). NOTE: This is the Diels-Alder adduct formed by reaction of 1,3-cyclopentadiene and maleic anhydride.* Both endo- and exoforms are present. Calibration stock solution, 50 mg/mL. Dissolve 500 mg analyte in ethyl acetate* to make 10 mL solution. Acetone.* Ethyl acetate.* Maleic anhydride.* Sorbent: acrylonitrile-divinyl benzene copolymer, 60/80 mesh, with surface area 100 to 200 m 2/g (Chromosorb 104, Johns-Manville). Nitrogen, purified. Hydrogen, prepurified. Air, filtered.

See SPECIAL PRECAUTIONS.

SPECIAL PRECAUTIONS: Maleic anhydride is a powerful irritant and can cause burns and pulmonary edema. Avoid exposure to concentrated vapor. Avoid contact with skin, eyes

SAMPLING: 1. 2. 3. 4.

1. Sampler: glass tube, 8.5 cm long, 6-mm OD, 4-mm ID, with plastic caps, containing two sections of coated sorbent (front = 100 mg; back = 50 mg), held in place and separated with glass wool plugs. Prior to packing, rinse the empty tube with acetone and dry to eliminate static adhesion of sorbent onto the tube wall. Pressure drop across sampler ≤2.5 kPa (25 cm water) at 0.05 L/min airflow. NOTE: See APPENDIX for preparation of coated sorbent. Use the coated sorbent within 20 days of preparation. Tubes available by special order (SKC, Inc.). 2. Personal sampling pump, 0.01 to 0.05 L/min, with flexible connecting tubing. 3. Gas chromatograph with FID, integrator, and column (page 2523-1). 4. Vials, 20-mL, with PTFE-lined caps. 5. Flask, round-bottom, 250-mL. 6. Rotary evaporator. 7. Vacuum oven. 8. Syringes, 10-µL, readable to 0.1 µL. 9. Pipet, volumetric, 10-mL, with pipet bulb. 10. Pipets, micro, 10- to 1000-µL.

Calibrate each personal sampling pump with a representative sampler in line. Uncap the ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.01 and 0.05 L/min for a total sample size of 1 to 5 L. Cap the samplers. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the front and back sorbent sections of the sampler tube in separate vials. Discard the glass wool plugs. Add 10.0 mL ethyl acetate to each vial. Attach cap to each vial. Allow to stand 15 min with occasional agitation.

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