Page:NIOSH Manual of Analytical Methods - 1009.pdf/2

This page needs to be proofread.

VINYL BROMIDE: METHOD 1009, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3.

4. 5. 6.

EQUIPMENT:

Ethanol, absolute.* Vinyl bromide (liquid), ≥ 98% purity.* Calibration stock solution, ca. 30 µg/µL. a. Accurately weigh ca. 5 mL ethanol in a stoppered 10-mL volumetric flask. b. Chill (0 °C) the flask, vinyl bromide and a 1-mL gas-tight syringe. c. Transfer 0.2 mL vinyl bromide to the volumetric flask with the gas-tight syringe. d. Allow flask to return to room temperature. Reweigh flask to determine mass of vinyl bromide transferred. e. Fill flask to mark with ethanol and calculate solution concentration. Nitrogen, purified. Hydrogen, prepurified. Air, filtered.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 10 cm long, 8-mm OD, 6-mm ID, with flame-sealed ends containing two sections of 20/40 mesh activated (600 °C) coconut shell charcoal; (front = 400 mg; back = 200 mg) separated by a urethane foam plug. A silyated glass wool plug precedes the front section and a urethane foam plug follows the back section. Pressure drop across the tube at 1 L/min airflow must be less 3.4 kPa. Tubes are commercially available (Supelco ORBO-32; SKC ST 226-09). 2. Personal sampling pumps, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. Ultrasonic bath. 4. Gas chromatograph, FID, integrator and column (page 1009-1). 5. Vials, glass, 25-mL, crimp seals or caps with FTFE-lined silicone rubber septa. 6. Pipet, 15-mL, with pipet bulb. 7. Syringes, 10-µL, readable to 0.1 µL; 1-mL, gas-tight, with valve. 8. Balance, readable to 1 mg. 9. Flasks, volumetric, 2-, 5-, 10- and 25-mL. 10. File, triangular. 11. Ice.

SPECIAL PRECAUTIONS: Ethanol (flash point = 12 °C) is a fire hazard. Vinyl bromide is suspect carcinogen. Prepare samples and standards in a well-ventilated hood.

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately know flow rate between 0.01 and 0.2 L/min for at total sample size of 2 to 10 L. Cap the samplers with plastic (not rubber) caps and pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the glass wool and front sorbent section in one vial. Place the back sorbent section and foam plugs into another vial. Add 15.0 mL ethanol to each vial. Attach crimp cap to each vial. Place vials in an ultrasonic bath for 30 min.

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