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Most reported measurement efforts for visualizing gaseous exposure signatures aim to detect and analyze continuous releases of volatile chemicals. Recently, we became particularly interested in characterizing short-time explosive releases of chemical substances. To perform such experiments, we pursued the construction of a suitable device that generates appropriate short-time events in a reproducible manner. This device, which we refer to as an aerosol bomb, allows the controlled release of liquids from 10 to 200 mL within a timeframe of one to two seconds after being pressurized up to 80 bar. Furthermore, different spray profiles and, thus, different cloud shapes can be created using customized spray nozzles. These short-time chemical exposures, however, proved challenging to visualize by video recordings as dilution and volatilization led to the rapid disappearance of visible cloud shapes. Therefore, we utilized a dual setup of passive infrared (IR) Focal Plane Arrays to detect and identify these lower concentrations of chemicals. In preceding studies, we have already shown the application of an IR focal plane array detector for hyperspectral recording and analysis of measurement fields of various sizes with 128 x 128 pixels in a time grid of two seconds. After connecting two hyperspectral imaging measurement systems into a combined dual setup, we conducted a three-dimensional (3-D) characterization of short-time chemical exposures, whereby 3-D imaging is realized by intersecting beams of IR waves.
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