The G. Budker Institute of Nuclear Physics of the RAS (Russian Academy of Sciences) Siberian Branch has developed a microdose radiographic system of inspection and admission control called SibScan.
Reacting to the slightest differences in density of substances, the system can detect not only firearms but also explosives and narcotics, which, being packed in superdense capsules, are usually carried in stomachs.
X-raying has been used for a long time to examine luggage at airports and railroad stations but in their case doses of X-ray radiation do not matter much. The SibScan system is not dangerous to people's health, because doses emitted by it are ultralow and commensurable with a standard daily dose coming from nature. A special software allows to process swiftly (within 10 seconds) information on passengers and visitors to banks, business offices, government departments and entertainment showplaces.
The computer monitor screen displays an image of person being scanned from shoe soles to headgear through outer clothing whatever it might be. The digital processing of received data makes it possible to get a high-contrast image with a clear picture of explosives and any dangerous objects made not only of metal but of plastics as well and hidden on the body or inside clothing.
Only this scanning mode lets meet such requirements as a high-contrast sensitivity and wide dynamic range necessary for detecting low-contrast objects inside clothing as well as on human body's thickest parts and inside its natural cavities; a fast checkup and analysis; ultra low doses of X-ray radiation commensurable with the natural ones; a large-sized image that by its height and width exceeds dimensions of human figure.
For the last twenty years the Institute of Nuclear Physics has been successfully developing low-dose digital radiographic systems of the scanning type (Siberia LDDRS) for medical examinations, which are now being manufactured by three Russian plants in Berdsk, Orel and the closed city of Lesnoy (Sverdlovsk-45) as well as in China (under the license). However, by contrast with them, the SibScan radiographic control system operates by the radically new principles of scanning and has a radiation detector as well as a software. The system's X-ray optics has been totally altered.
The flat-field collimator cuts out from X-ray tube's radiation a thin, flat and fan-shaped beam of X-rays, which is recorded by a linear detector after having passed through the object that is being checked. The detector's data on distribution of radiation along one “line” of the image is stored in the memory every 2.5 msec. As soon as the scanning is over, the whole image consisting of 2,000 rows is fed into the computer and after a swift processing it appears on the display.
Superficially, the SibScan radiographic control system consists of two posts made of nontransparent material and a person being checked does not see the system's moving parts. The high-voltage power supply and cables are inside the left post. The scanning is started with shoe soles and it is over, when the detector gets evenly illuminated, i.e. at the moment of the beam leaving a person's head.
The Novosibirsk system operates as much as two or even three times faster than the similar foreign systems, its design is more convenient for use and the system costs less. For example, the Conpass system being made in Belarus costs about $250,000, the price of the American-made Secure-1000 system comes up to $110,000 and the price of the Scannex system developed by specialists from the company De Beers to prevent diamond-stealing amounts to about $500,000. Even so, the Secure-1000 system, for one, operates by the principle of “palpating” object's outer parts with X-ray and recording of scattered radiation; it does not guarantee detection of dangerous items hidden in human body's cavities, under tight clothing or inside shoes.
Under the Russian law the annual permissible dose during examinations that have nothing to do with the diagnostic medical ones should not exceed 1,000 µSv. The same annual dose is effective in Western Europe. When using the SibScan system the dose during a checkup does not exceed 3 µSv. This means that a person can undergo checkups with the use of the SibScan system 200 times a year without any harm to one's health.
The pilot sample of the SibScan system has been made by Japan's Kawasaki Heavy Industries under the contract with the Institute of Nuclear Physics. It is completely prepared for a commercial production. All the more so since both domestically produced and foreign-made components, such as X-ray emitters, linear guides, computer equipment, can be used. The total cost of purchased components is about $70,000, while, by specialists' estimates, the volume of the potential sales market is coming close to $1 billion.
Microdose X-ray control systems for inspections in places of people's mass gatherings can be put into a commercial production in the shortest possible time and with minimal costs.