National Institute for Occupational Safety and Health

“ Calibrate daily with at least six working standards. a. Add known amounts of toluene to CS2 in 10-mL volumetric flasks and dilute to the mark to produce toluene concentrations in the range 0.01 to 10 mg/mL. b. Analyze with samples and blanks (steps 8 through 10) . c. Prepare calibration graph (peak area vs. mg/mL toluene) . 6. Determine desorption efficiency (DE) in the calibration range at least once for each lot of samplers used. Prepare three samplers at each of five concentrations plus three media blanks. a. Place the collection element of a media blank sampler into a vial and cap. ”

“ Make sure sampler inlets are unobstructed. Record start of sampling time. Follow manufacturer's recommendations to estimate appropriate sampling time based on relative humidity and suspected concentration of toluene. NOTE: The uptake constant is only valid for samplers in air with ambient velocity higher than ca. 10 cm/sec. For area samples, ensure adequate air movement. 2. Terminate sampling by sealing the sampler as recommended by the manufacturer or by transferring, in a toluene-free environment, the activated charcoal collection element to a vial and sealing the vial with a septum cap. ”

“ Generated concentrations were independently verified.
REFERENCES: [1] [2] [3] [4] [5]
Perkins, J. B., N. H. Price, L. Eggenberger and J. A. Burkart. Evaluation of Passive Organic Vapor Monitors, available as PB83-221028 from NTIS, Springfield, VA 22161 (1981) . NIOSH Manual of Analytical Methods, 3rd ed., V. 2, NMAM 1500, 1501. U.S. Department of Health and Human Services, Publ. (NIOSH) 84-100 (1984) . Rodriguez, S. T., D. W. Gosselink, and A. E. Mullins. "Determination of Desorption Efficiencies in the 3M 3500 Organic Vapor Monitor," Am. Ind. Hyg. Assoc. ”