Bar-Code For Explosives

Barely visible dust layer in the place of explosion would tell specialists where and when the explosive was produced. To this end, the dust should be preliminarily marked up in the way suggested by Russian researchers. The project was sponsored by the International Science and Technology Center.

When investigating the locus delicti after the explosion the experts face a significant problem. They can determine with high probability the kind and capacity of explosive device used by terrorists and the explosive it was filled with. However, the most important question – where and when the explosive was produced – usually remains unanswered: trotyl is trotyl regardless of the place and date of its production.

Specialists of the Semenov Intitute of Chemical Physics, Russian Academy of Sciences, and their colleagues from several defense enterprises have developed special coding additives. If they are introduced in the explosive composition, then peculiar “finger-prints” will remain in the place of explosion, judging by which specialist can identify the explosive and track routes of its legal migration, thus providing investigation with a clue for disclosing terrorists’ supply channels. This important researchers’ effort has been sponsored by the International Science and Technology Center.

It should be noted that it is very difficult to produce such coding additives particularly for explosive – too many requirements are set forward. On the one hand, the additives themselves should be absolutely harmless both for the product (i.e., explosive) and for the environment. In no circumstances radio-active coding additives or such additives that could worsen explosive characteristics should be used.

On the other hand, the explosion, i.e. high temperature and pressure, should not damage coding additives. It doesn’t matter even if the additives get somehow transformed in these extreme conditions. The most important thing is that they do not lose their coding properties. And certainly they should be very specific to make identification reliable. No admixtures should prevent from recognizing markers or should mix them up.

However, these challenges did not impede the researchers from the Semenov Intitute of Chemical Physics, Russian Academy of Sciences, specialists of the highest category in the area of physicochemistry of explosives, spectrography and applied mathematics, to solve the problem. The coding additives they have suggested to introduce in the explosive composition would not spoil it, and upon the explosion they would not deteriorate themselves or damage the environment.

“These are the finest grains of aluminum alloy, says the project manager, head of the laboratory Yuri Karasevich. But this is not an ordinary aluminum alloy, but a peculiar one. It contains substances called rare earths or rare earth elements. It is because they are very scarce in nature and they are dispersed along the earth’s crust. So, they cannot be found in any meaningful quantities in special predetermined combinations either in natural or handmade objects. However, they can be found in the place of explosion if they have been preliminarily into the explosive composition.”

Evidently, it is more complicated to identify such “fingerprints” than to read information from bar-codes in a supermarket. Identification actually requires carrying out complicated chemical analysis of microsamples. Specialists should determine the quantity of rare earth elements contained in the sample, what particular rare earth elements are contained in it and in what combination. Nevertheless, the researchers have managed to cope with this challenge.

For analytical procedure, the authors have suggested to use the laser emission method of analysis of elemental composition with the help of equipment developed by the ‘Typhoon’ research-and-production association. In case of such research, the sample is first converted into plasma at the temperature of 50 to 60 thousand degrees C, and then electric discharge is let pass through plasma. Judging by the radiation spectrum, specialists determine the particular elements contained in plasma. The researchers have also developed the necessary technique and complicated software for statistical spectrum analysis.

First trials have already been carried out by the researchers. They have studied properties of the “coded” explosive on a special test bench in the blasting chamber and made sure that it blows up in a proper way – no worse that the parent explosive does. The researchers have also come to the conclusion that it leaves correct “finger-prints” that allow to identify the explosive as reliably as the goods are identified by the bar-code. So, the researchers have solved their task. It is up to the politicians now. A respective international convention is needed to have all explosives marked up in this way. Hopefully, the convention will be in place some day.