Bridging the Security Gap in Detection Systems

The traditional emphasis on verifying the security status of passenger baggage has resulted in a technically sophisticated array of x-ray screening equipment that can automatically detect a variety of potential threats. A parallel area of development can be found with regard to enhancing the skills of screening staff. When looking for suspect items, operatives need to be well-trained and experienced in analysing x-ray images of baggage. Due to the growing range and sophistication of potential threats, security operatives are being challenged by an increasing and more complex workload against a background of ever-greater passenger numbers. Therefore, any assistance that technology can offer the screener is more than welcome.

Regular, specialist, operators' training courses ensure security and experience, leading to considerably improved detection rates for conventional weapons. However, results also show that explosives are often tricky to identify in an x-ray image.

Complex Explosive Substances

X-ray images of explosives can be difficult to distinguish from those of harmless organic objects. As explosives have no definite shapeor structure, the operator can often have no clear clues to help identify the potential threats, so in these cases, the effectiveness of their training can be rather limited. Covert testing results and the data from operational threat image-projection systems have shown thatthere is considerable room for improvement with regard to improving the screeners' ability to detect complex threats. Although the same staff has proved very able to detect guns and knives, it has become evident that the recognition of improvised explosive devices must be advanced if the industry is to achieve the highest standards of safety and security. It is, therefore, essential to support theoperator with the appropriate technology at this point. This assistance has become even more important with the 'appearance' of liquid explosive substances and we at Smith's Detection believe that extendingthe automated detection capability for screening carry-on baggage atpassenger checkpoints could reduce the possibility of threat materials entering the secure areas of airports.

Proven Technology

There are already a number of operational x-ray inspection systemsin use that can detect commercial and military explosives as part ofthe automatic hold baggage screening process.

However, the new challenge for operatives and machines alike is the so-called binary or improvised explosive liquids, or their individual components. As their physical and chemical properties are difficult to distinguish from harmless liquids, the emergence of an alleged plot to use liquid-based explosives to destroy transatlantic airlines led to the introduction of a total ban on the carriage of liquids on passenger services back in August. Although this initial ban has since been relaxed, at the time of writing, the carriage of liquids is still restricted. As a result, Smiths Detection is addressing the need to enhance carry-on baggage screening capabilities through its development of the new HI-SCAN 6040aTiX x-ray inspection system for the automated detection of explosive threats. The starting point for the 6040aTiX was the proven explosives detection system (EDtS) concept for automatic explosives detection in checked baggage. If required, the HI-SCAN system is capable of 'alarming' any kind of non-solid baggage content--a tremendous advantage over current checkpoint security systems.

6040aTiX--The Hard Facts

The 6040aTiX combines the proven HI-SCAN 6040 technology with the advanced features of proven multi-view technology, and yet representsa completely new stage of development.

The system offers an even greater technical advantage, giving higher security levels by providing automatic evaluations through using the latest x-ray technology. Being a multiple-beam machine, it is equipped with a number of x-ray generators that produce independent imageand data results. Several fan-shaped x-ray beams scan each item of baggage. The various x-ray generators, configured in complementary positions, emit beams from different angles, which, when combined, will produce the data required to achieve the highest levels of explosivesdetection currently achievable. The actual explosives detection process employed by the HI-SCAN 6040aTiX is based on the processor-generated analysis of the density and relative atomic weight of the materials. This works by using Zeffective (the effective atomic number) and volume/density algorithms to provide material classifications.


Whenever new screening equipment is produced, there is always the question of how can it be integrated into an airport's existing checkpoint system. Obviously, with regard to the amount of space availablefor such installation, each airport must be treated as a separate case. However, the 6040aTiX has been specially designed to have a minimum 'footprint' and can, therefore, be integrated into existing security inspection positions without difficulty. This is true for the whole system, from entry to exit points.

Last but not least aTiX is able to use Threat Image Protection methods (such machines are commonly referred to as being 'TIP-capable').This technology allows the screener's ability to be tested in two different ways. Firstly, complete x-ray images of fictional baggage items 'containing' threat items can be automatically projected between the images of real bags, or, secondly, the images of individual threatitems can be projected 'inside' real x-ray images. It is impossible for the screener to tell if he or she is looking at a real bag, or a false projected image, so it has proven to be an excellent training aid. The x-ray's findings are shown to the operator on a monitor--a tremendous help for the staff, and we consider it to be a milestone in the reliable inspection of carry-on baggage.

The HI-SCAN 6040aTiX offers the operator two different x-ray images for visual baggage inspection, both are detailed pictures of the bag's contents from two significantly different angles. The two very high-resolution images give the operator the opportunity to identify dangerous objects quickly and accurately. Obviously, the quicker the operative can clear the alert given, the quicker the overall security check process becomes.

Threat Resolution

--Complementary Technologies

In order to resolve the threat alarms raised by 6040aTiX, and to confirm the actual nature of the substance detected, Smiths Detection offers a wide range of threat resolution technologies. For example, the new Smiths Detection lightweight, hand-held RespondeR spectrometer, can identify unknown solids and liquids. Users decide whether to carry out an analysis by using its integrated sample compartment or itsoptional 'point-and-shoot' capabilities. Either way, the results will be reliable, accurate and available in less than 30 seconds. RespondeR is a Raman-based chemical identifier because Raman technology is ideal for identifying samples through glass or plastic bags, in mixtures, or in water.


To guarantee a secure aviation environment while reassuring the public's perception of flight safety, it is commonly agreed that the operational standards of airport checkpoints need to be raised continually. The remedy of known deficiencies through procedures, processes and technical innovation is a paramount objective of security system manufacturers. The plan is to provide a comprehensive and efficient means of passenger screening within the framework of the present security checkpoint set-up. Technologies, such as the Smiths Detection aTiX-system, have the potential to achieve the highest standards of security screening, without compromising passenger or bag throughput, enabling its users to achieve a safe, secure and resilient aviation system. 6040aTiX represents the next generation in carry-on baggage explosives detection, and, in combination with other technologies, it provides a comprehensive checkpoint of the future.