Passive Cryogenic Whole Air Field Sampler.
Fernandez-SJ; Motes-BG; Dugan-JP Jr.; Bird-SK; McManus-GJ
NIOSH 1991 Feb:653-655
A passive cryogenic sampler was developed for the collection of whole air samples without loss or concentration of any atmospheric constituents. The principle of operation was the collection by bulk gas flow and condensation of a whole air sample into a previously evacuated cylinder surrounded by a liquid nitrogen reservoir. The sample evaluation was performed in three phases. The first phase determined sample flow rate, sample size, resultant sample pressure, and sample collection lifetime as a function of the liquid nitrogen additions. The second phase analyzed simulated whole air samples for bulk composition, noble gases, selected chlorofluorocarbons, and tritium (10028178) before and after collection in the cryogenic air sampler. The third phase involved collection of actual field samples and analysis for bulk composition and chlorofluorocarbon content. Operation of the sampler did not require electrical power, so that it could be used where potentially explosive gas mixtures are found. The sampling lifetime can extend to 4 hours with refilling of the liquid nitrogen reservoir.
Air-sampling; Air-sampling-equipment; Environmental-contamination; Environmental-pollution; Sampling-methods; Halogenated-hydrocarbons; Organic-vapors; Toxic-gases; Explosive-atmospheres;
Field Screening Methods for Hazardous Wastes and Toxic Chemicals. Second International Symposium, February 12-14, 1991. Sponsored by U.S. EPA; U.S. DOE; U.S. Army Toxic and Hazardous Materials Agency; U.S. Army Chemical Research Development and Engineering Center; U.S.A.F.; Florida State Univ.; National Environmental Technology Applications Corp.; and NIOSH