Promet (Zagreb) (May 2006)
Port Security: Container Cargo Control
Abstract
illicittrafficking of threat materials, especially explosives, chemicalsubstances and radioactive or nuclear material. The transportof the threat materials by using sea routes is an advantageto te"orists especially because of the possible use of ship containers.The container is the basis of world trade. It is assumed thatthe world total movement in containers is about 200 millionTEUs ("20-foot equivalent units") per year. The list of materialstransported by containers which should be subject to inspectionwith the aim of reducing the acts of te"orism includes explosives,narcotics, chemical weapons, hazardous chemicalsand radioactive materials.Of special interest is nuclear te"orism. The risk of nuclearte"orism carried out by sub-national groups should be considerednot only in the construction and/or use of nuclear device,but also in possible radioactive contamination of large urbanareas.The system of ship containers control is an essential componentof «smart border» concept. Modem personnel, parcel,vehicle and cargo inspection systems are non-invasive imagingtechniques based on the use of nuclear analytical techniques.The inspection systems use penetrating radiations: hard x-rays(300 keV or more) or gamma-rays from radioactive sources(137Cs and 60Co with energies from 600 to 1300 keV) that producea high resolution radiograph of the load. Unfortunately,this information is "non-specific" in that it gives no informationon the nature of objects that do not match_ the travel documentsand are not recognized by a visual analysis of the radiographicpicture. Moreover, there are regions of the containerwherex and gamma-ray systems are "blind" due to the high averageatomic number of the objects i"adiated that appear asblack spots in the radiographic image.The systems being developed are based on the use of fast, 14Me V, neutrons with detection of associated a-particle from nuclearreactionbywhichneutrons are produced (d+t>a+n).Jnsuch a way the possibility to determine object location inside aclosed container is obtained. This information is contained inthe measured time interval between the detection of the associateda-particle and the detection of y-rays produced by neutronsin the investigated object by (n, y) and/or (n, n'y) reactions.The object identification is performed by the analysis ofcoincidence gamma rays energy spectrum.Results obtained so far on the implementation of NATOSfP-980526 project «Control of Illicit Trafficking in ThreatMaterials» and EU FP6 project «European Illicit TraffickingCountermeasures Kit, EURITRACK» have shown that it ispossible to construct a multisensor system with a fast controlsensor using x-rays (whole container) followed by detailed elementalanalysis of suspect volume by a neutron sensor.
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