Incidents in air cargo, such as hidden explosives in Ink cartridges from Yemen in 2011, clearly show the threads of terrorism. Although this cargo has been checked with X-ray systems several times, the explosives were detected very late. Innovative research and development of efficient and effective systems can make a decisive contribution to achieve a fast and reliable detection of hazardous substances in airfreight.
In the "ChemAir" project, an airfreight-specific detection system based on a mass spectrometer is developed. Airfreight can be reliably checked for hazardous substances in a short time. In order to provide suitable technology for the user, the system has to be able to detect a wide range of hazardous substances under realistic conditions: The new system enables the detection of even the smallest amounts of substances from the air, even in the interior of the cargo.
In order to achieve these project objectives, research must be carried out at different levels. In addition to developing the single technological components of the detection technology, an evaluation and operating software is to be developed.
The aim of the project was the development of a fast vacuum gas chromatography method to detect dangerous substances in air freight. For that reason, a Soft Ionization–Time of Flight–Mass Spectrometer (SI-TOF) and a Vacuum Gas Chromatograph (GC) were installed and tested at the Bundeswehr Research Institute for Protective Technologies and NBC-Protection. During the method development and optimisation, the ionization energies of the soft ionization time of flight mass spectrometer (SI-ToF) were varied between 10 eV and 70 eV. The investigated energies showed significantly different fragmentation pattern in the case of the tested substances. The combination of fragmentation pattern at the different energies allows the reliable detection and identification of the tested substances. For the conducted tests several explosives and simili of chemical warfare agents (CWA) were used as examples for hazardous materials on the TOF and the GC system. The results of the CWA-simili were compared with spectra of the same compounds which were measured on a Proton-Transfer-Reaction-Mass Spectrometer (PTR-MS). Finally, the project showed that it is possible to reduce the run-time of a GC-MS-System for the identification of dangerous goods significantly by the combination of the developed vacuum gas chromatograph and an advanced mass spectrometer.
Findings of the study are published in detail by several final reports of the project partners (German only) which are available online via the German National Library of Science and Technology (TIB):
Overall report (Bundeswehr Research Institute for Protective Technologies – NBC-Protection):
University of Bonn, Institute of Agricultural Engineering: