Remote and In Situ Sensing of Hazardous Materials by Infrared Laser Absorption, Ion Mobility Spectrometry and Fluorescence.
NIOSH 1991 Feb:167-172
A remote sensing infrared differential absorption lidar based on the coherent detection of backscattered carbon-dioxide laser light was developed. The lidar can be used for the detection of a wide range of molecular pollutants in the atmosphere from ranges of a few kilometers along a path to a topographic target. Results of field measurements to detect molecular pollutant clouds are presented in the kilometer ranges. An ion mobility spectrometer was also discussed which has been developed for in-situ measurements of impurities in the air. Reliable detections of concentrations of 0.1 milligram per square centimeter for 2,2-dichlorovinyl-dimethyl- phosphate (62737) were achieved with a measurement time of less than 5 seconds. Compared with methods requiring probe sampling, this method operated without physical contact, was not influenced by the surface type, and was highly selective. The application of the method required spraying the contaminated area, illuminating it with ultraviolet light, detecting the frequency shifted fluorescent light, and evaluating the detector signal.
Analytical-chemistry; Chemical-analysis; Analytical-methods; Air-quality-monitoring; Environmental-pollution; Toxic-gases; Hazardous-materials;
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