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People sniffer was the field name for a series of U.S. Army personnel detectors used during the Vietnam War. The purpose was to detect enemy soldiers in hidden positions, as very frequently happened in the jungle combat conditions of Vietnam.

The detection method used by people sniffers depended on effluents unique to human beings; such as those found in urine and sweat. The U.S. military used two different versions of the people sniffer, one backpack version and one helicopter-mounted version.