ALLYL CHLORIDE: METHOD 1000, Issue 2, dated 15 August 1994 - Page 2 of 3
REAGENTS:
EQUIPMENT:
1. Benzene, chromatographic quality.* 2. Allyl chloride. 3. Hexane. 4. Calibration stock solution, 7.5 µg/µL. Dilute 75 mg allyl chloride (80.0 µL at 20 °C) to 10 mL with hexane. 5. Nitrogen, purified. 6. Hydrogen, prepurified. 7. Air.
- See SPECIAL PRECAUTIONS.
1. Sampler: glass tube, 7 cm long, 6-mm OD, 4-mm ID, flame-sealed ends, containing two sections of activated (600 °C) coconut shell charcoal (front = 100 mg, back = 50 mg) separated by a 2-mm urethane foam plug. A silylated glass wool plug precedes the front section and a 3-mm urethane foam plug follows the back section. Pressure drop across the tube at 1 L/min airflow must be less than 3.4 kPa. Tubes are commercially available. 2. Personal sampling pump, 0.01 to 1 L/min, with flexible connecting tubing. 3. Gas chromatograph, flame ionization detector, integrator, and column (page 1000-1). 4. Vials, 2-mL, PTFE-lined caps. 5. Syringe, 10-µL, readable to 0.1 µL. 6. Volumetric flasks, 10-mL.
SPECIAL PRECAUTIONS: Benzene is a suspected human carcinogen. All work should be performed in a hood. SAMPLING: 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 1 L/min for a total sample size of 16 to 100 L. 4. Cap the samplers with plastic (not rubber) caps 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 benzene to each vial. Attach crimp cap to each vial. 7. Allow to stand 30 min with occasional agitation. CALIBRATION AND QUALITY CONTROL: 8. Calibrate daily with at least six working standards over the range 0.01 to 1.5 mg allyl chloride per sample. a. Add known amounts of calibration stock solution to benzene in 10-mL volumetric flasks and dilute to the mark. b. Analyze together with samples and blanks (steps 11 and 12). c. Prepare calibration graph (peak area vs. mg allyl chloride). 9. Determine desorption efficiency (DE) at least once for each batch of charcoal 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 calibration stock solution directly onto front sorbent section with a microliter syringe. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition
