| abstract |
Devices, apparatus and methods are disclosed for non-contact pneumatic sampling and sampling of surfaces, persons, articles of clothing, buildings, furnishings, vehicles, baggage, packages, mail, and the like, for contaminating aerosols or vapors indicative of a hazard or a benefit, where the contaminating aerosols or vapors are chemical, radiological, biological, toxic, or infectious in character. In a first device, a central orifice for pulling a suction gas stream is surrounded by a peripheral array of convergingly-directed gas jets, forming a virtual sampling chamber. The gas jets are configured to deliver millisecond pneumatic pulses that erode particles and vapors from solid surfaces at a distance. In another aspect of the invention, a suction gas stream is split using an air-to-air concentrator so that a particle-enriched gas flow is directed to a particle trap and particles immobilized therein are selectively analyzed for explosives and explosives related materials under optimized conditions for analyzing particle-associated constituents and a bulk flow is directed to a vapor trap and free vapors immobilized therein are selectively analyzed for explosives and explosives related materials under optimized conditions for analyzing free vapors. Detection signals from the particle channel and the vapor channel are compared or integrated to detect trace residues associated with explosives. |