Detecting Explosives and Chemical Warfare Agents on Common Surfaces

Kurzfassung

The ability to detect harmful substances on surfaces is of high relevance in civil security applications as well as in military scenarios. Laser-based techniques, e.g. Raman and fluorescence spectroscopy, are frequently proposed for a variety of applications that require contactless and fast detection of surface-bound hazards. However, detection of chemicals and explosives on unknown surfaces is generally trying, due to the contribution of the background material to the spectral signatures. A dedicated data analysis can reduce the influence of the surface and improve the reliability of detection. In this study we investigated the potential of Raman and infrared reflexion spectroscopy for the detection of explosives as well as chemical warfare agents and simulants on different surface materials. The hazardous substances include organic and inorganic explosives, like RDX and ammonium nitrate, chemical warfare agent simulants, such as tributyl phosphate, and live agents, e.g. VX. The samples were investigated at a distance of about 75 cm in a standoff backscattering configuration in a laboratory setting. A live data analysis was performed during measurements using a real-time automated detection pipeline trained for the detection of explosives. For verification purposes of the pipeline results, a separate data analysis was performed afterwards. The results highlight the strengths and weaknesses of both detection methods, allowing for a more targeted system design according to specific needs of different scenarios.