DETECTIVE WORK
The ability to detect minute traces of explosive substances - or substances that can form part of improvised explosive devices (IEDs) - can provide valuable protection in a wide range of situations. Security Middle East looks at the latest developments in hand-held and mobile explosives detection
From customs and border points, embassies, government offices and high profile public sites, through to private businesses – explosive detection equipment can form an essential line of defence against terrorism and other potential bomb threats.
Designed to identify minute trace particles of suspect materials on people, clothing and objects, a range of devices are now available in hand-held, portable or fixed (eg table-top) models. These detectors can not only identify potential threats and help to find evidence during investigations, but also make it harder for successful terrorist attacks to be mounted, and even act as a deterrent.
In day-to-day operations in areas such as mail sorting rooms and baggage handling areas, so-called non-contact trace detection can be used to quickly identify and isolate suspect items without significantly delaying operations.
Peroxide-based threats
Acro’s recently launched ACRO-P.E.T. is a pen-like tester (pictured above) that has been designed to rapidly detect peroxide-based explosives on contact. Acro claims it is capable of detecting less than 50 micrograms (0.00005g) of Triacetone Triperoxide (TATP). The US army recently ordered 300 of the devices to detect home-made bombs. TATP has been identified in a number of terrorist cases but can be hard to detect when found in a colourless, liquid form.
Peroxide was a key ingredient in the home-made bombs that killed 52 people in London two years ago and Acro say it is increasingly being used by terrorist organisations around the world. Basic ingredients for peroxide-based bombs are available from most DIY stores, often in bulk.
Newest dual-mode option
The MobileTrace simultaneous dual-mode handheld detector, launched this month by GE, is designed to expand the range of target explosives that can be identified in a single sample.
The company’s patented ITMS technology (Ion Trap Mobility Spectrometry) offers the level of explosives (and narcotics) detection used at maximum security locations such as military bases and border crossings. While most explosives have negative ion affinity, says GE, some important exceptions have positive ion affinity. The MobileTrace uses the same detection system, in a hand-held model, which is deployed in its desktop itemiser device. This system detects both.
Historically hand-held devices have worked in only one mode at a time, and require components to be changed and additional samples to be taken for testing both types of ions. The MobileTrace gives users the flexibility to swipe surfaces for trace particles or to analyse vapours.
‘Sniffer’ technology
Fido explosives detectors use proprietary amplifying fluorescence polymers (AFP) to detect trace levels of explosive materials in parts per quadrillion (ppq). The company claims that this level of detection is comparable to that of highly trained explosives detection canines, the gold standard in explosives detection technology.
The AFP detection technology used in the Fido explosives detectors was designed for use as an explosives ‘sniffer.’ As such, the Fido can detect the vapour emanating from explosive materials without having to come in contact or direct line of sight with the explosive device itself.
The Fido XT can be configured in multiple formats to accommodate the needs of most explosives detection applications. The system includes a control unit and separate sensor head where actual explosives detection takes place. These two components can be connected directly for one-handed explosives detection operations or via tether for added manoeuvrability. In addition, the sensor head can be mounted for benchtop applications.
Due to its size and trace vapour detection capability, the Fido XT can be easily integrated as a payload onto robotic vehicles for remote explosives detection applications. Dependent upon the robot, this can be accomplished either by inserting the entire system onto the robotic platform or by attaching the sensor head to a robotic arm.
The Fido provides real time explosives detection for practical screening operations. Actual detection of explosive materials occurs in the sensing element and has a reversible detection response, allowing it to be reused many times. After a positive explosives detection reading, the Fido takes only seconds to before screening the next target.
Detection results are displayed in real time on the LCD screen and through an optional audio signal similar to that of a Geiger counter.
Electro-optical ionization devices
Implant Sciences Corporation recently confirmed an order for eight of its Sniffer handheld explosives detectors from Iraq’s Ministry of the Interior.
Implant Sciences uses ion beam technology to develop, manufacture and market products, including trace explosives detection systems for security and defence applications.
The company’s Quantum Sniffer employs a novel technology for the detection of explosives vapours that it claims is more sensitive than alternative detection devices. The technique detects the presence of parts per trillion (ppt) of explosives molecules, without physical contact and in real time. The patented vortex sample acquisition system collects the sample, ionizes it with an electro-optical ionization scheme, identifies the sample via standard ion mobility technology and, if an explosive is present, will produce a visual and audible alarm. The LCD will display the identity of the explosive present and the audible alarm can be switched off if required.
Quantum Sniffer is claimed to be the only explosives trace detector with true automatic self-calibration – no user intervention is required.
Another option, Implant Science’s QS-H150 portable explosives trace detector, was developed in conjunction with the US Navy. The device is capable of detecting trace amounts of most commercial and military explosives, including RDX, PETN, HMX, TNT, black powder and ammonium nitrate at nanogram level concentrations.
The detection is real time with immediate cleardown, which dramatically improves throughput. The instrument is non-contact and does not use expensive consumables. The QS-H150 uses the company’s proprietary opto/electrical ionization technique rather than a radioactive source for ionization and hence there is no need to deal with complicated NRC regulatory requirements.
Wide ranging detection
The SABRE 4000 from Smiths Detection is claimed to be the only portable trace detector that can detect threats from explosives, chemical warfare agents, toxic industrial chemicals or narcotics. It can do so in approximately
20 seconds. With a cold time start of 10 minutes and weighing approximately 7 lbs, including the 4-hour battery, the SABRE 4000 is a small, powerful tool for use against terrorism and drug trafficking.
With the added detection capability, new features such as the colour TFT display and standard 4-hour battery, the SABRE 4000 is marketed as the smallest, lightest hand-held trace detector available, capable of detecting and identifying multiple threats.
Proper sample collection is key to the success of any trace detector, says the company. The versatile SABRE 4000 is capable of analyzing either trace particle or vapour samples, allowing the operator to apply the ideal sampling technique for the substance suspected.
For example, most explosive and narcotic substance do not have a strong vapour presence and in the real world are very difficult to detect by vapour. Therefore, the most reliable collection and analysis method for those substances is particle collection. By contrast, the nature of chemical agents and toxic industrial chemicals makes vapour sampling more appropriate for these substances.
The SABRE 4000’s ability to analyse either trace particle or vapour samples lets the operator decide which sample collection method will yield the most accurate analysis results
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 Further information on the devices mentioned in this article can be found by visiting the following websites:
The ACRO-P.E.T. –www.acrosec.com
The SABRE 4000 – www.smithsdetection.com
The Quantum Sniffer – www.implantsciences.com
The Fido range – www.nomadics.com
MobileTrace – www.gesecurity.com
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