National Institute for Occupational Safety and Health

“ 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. Connect the drying tube to the front section of the charcoal tube with a 20-mm section of PTFE tubing. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 2 to 25 L. NOTE: Samples may be taken up to 1 L/min if ambient humidity is low [3,4] . Keep the drying tube connected to the charcoal tube during shipping. ”

“ The working range is 10 to 200 mg/m 3 (3 to 64 ppm) for a 5-L air sample and is applicable to ceiling determinations. Better sensitivity may be obtained by using higher sampling rates if high humidity is not present [3,4] . This method has been used extensively in the viscose rayon industry and at carbon disulfide production facilities.
INTERFERENCES: No interference occurs from hydrogen sulfide [4] . Water vapor is a potential sampling interferant [4] which is removed by the drying tube. ”

“ Breakthrough (with drying tube preceding charcoal tube) occurred at 162 min (100% RH, 40 ppm CS 2, 0.2 L/min sampling rate) = 32.4 L; DE (0.28 to 1.12 mg/sample) = 0.86; storage stability (0.56 mg/sample) = 85% recovery after one week at 25 °C. At a 1 L/min sampling rate, breakthrough occurred at 19 L at 100 mg/m 3 [4] . A user check of this method gave an estimated LOD of 0.02 mg CS 2 per sample [2] .
REFERENCES: [1] Documentation of the NIOSH Validation Tests, S248, U.S. Department of Health, Education, and Welfare, Publ. ”