Design and laboratory evaluation of a breath sampling respirator for organic solvent biological monitoring.
Morgan MS; Litzinger MH; Cordts ST
Appl Ind Hyg 1988 Feb; 3(2):41-46
A breath sampling respirator for organic solvent biological monitoring was described. The sampler was based on a half face dual cartridge respirator whose inhalation ports were fitted with standard air purifying elements. The upper part of the cartridge contained four layers of activated charcoal cloth mounted in pairs separated by Teflon gaskets which adsorbed organic solvent vapors. The lower section contained 70 grams (g) of 8 to 12 mesh molecular sieve of 3 angstrom pore size that collected water vapor in order to determine the volume of exhaled air. The loaded cartridge weighed about 180g. Airflow resistance due to the cartridge was not more than 2 centimeters of water at flow rates up to 1 liter per second. After sampling, adsorbed organic vapors were desorbed in carbon- disulfide and analyzed by gas chromatography. Collected water vapor was determined gravimetrically. In laboratory simulation experiments, controlled atmospheres containing 0.75 to 150.0mg/m3 toluene (108883) at relative humidities of 80 or 90 percent were passed through the sampler and the extent of toluene recovery was determined. Recovery was around 70 percent for toluene concentrations up to 60.0mg/m3. Six volunteers wore the sampler while at rest or walking on a treadmill. The volume of expired air and weight gain of the molecular sieve in the cartridge were measured. The weight of water vapor collected was well correlated with the volume of exhaled air. Nine male volunteers breathed 150mg/m3 toluene for 4 hours. Seventeen to 20 hours later they were tested using the sampler. The mean toluene concentration was the respirator/sampler can be used for monitoring of most solvents that are adsorbed on charcoal, with only minimal job disruption.
NIOSH-Publication; NIOSH-Grant; Industrial-hygiene; Organic-vapors; Air-sampling; Laboratory-testing; Aromatic-hydrocarbons; Humans; Equipment-design; Exposure-levels
Applied Industrial Hygiene
Environmental Health University of Washington Mail Stop SC-34 Seattle, Wash 98195