National Institute for Occupational Safety and Health

“ Sampler: glass tube, 7 cm long, 6-mm OD, 4mm 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 0.1 L/min, with flexible connecting tubing. 3. Gas chromatograph, FID, integrator and column (page 1002-1) . 4. Micro-distillation apparatus for vacuum distillation of chloroprene. 5. Vials, 2-mL, glass with PTFE-lined septa and crimp seals. 6. Syringe, 10-μL, readable to 0.1 μL. 7. Volumetric flasks, 10-mL. 8. Pipets, 1-mL, graduated in 0.1 mL, with pipet bulb.
SPECIAL PRECAUTIONS: Carbon disulfide is toxic and flammable. ”

“ Calibrate daily with at least six working standards over the range 0.03 to 0.5 mg chloroprene per sample. a. Add known amounts of calibration stock solution below the surface of CS 2 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 chloroprene) . 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 concentrations plus three media blanks. a. ”