On Bombs and other ExplosivesMonday, 18 October 2010
Explosive materials can explode only if subjected to impact, friction, or an increase in temperature. Friction will cause a change in the chemical structure of an originally stable explosive material, and if subjected to impact will produce a massive explosion or flaming fragments. Apparently, making explosives is not too difficult, because all materials can produce a chemical reaction that results in an explosion. What’s more, explosive materials are easily to be found in the mining and exploration industries. They are also used in quarrying and fishing.
According to the two classifications of explosives—high explosives and low explosives, high explosives are more accurately called bombs. Bombs consist of a battery, detonator, tapes, wire, and may be made from metal, glass, wood, paper or plastic, among others. High explosives are, of course, far more dangerous than low explosives.
One example of a high explosive is emulsion, or a mixture of ammonium nitrate, aluminium and sulphur. Ammonium nitrate itself is a very commonly used commercial explosive and is easy to mix. Other high explosives include PETN, RDX, and Semtex (a mixture of RDX and PETN originating from Czechoslovakia, Eastern Europe, commonly used by terrorists). This compound is then given a code ‘C’ (for compound), ranging from C1, C2, C3, to C4. All use RDX. The difference is the plasticizer, and the occasional addition of TNT and PETN. C4 has the highest RDX content and as such has the greatest destructive power. TNT, RDX, PETN, and C4 (a combination of RDX + PTEN + TNT) are classified as military explosives. A C4 bomb is a highly sensitive, plastic high explosive bomb, used exclusively for military purposes (for example for blowing up bridges). It is compact, and may be in the form of a small rod or square, and can be detonated using a timer, remote control, ignition key, and so on. It is produced in America and Europe. Sensitive to vibration, light and dark, C4 is frequently used by the military for demolition work and is only used by special forces. Unfortunately, it is not known whether our special forces (Kopassus) and anti-terrorist unit use this high explosive or not, bearing in mind that the police has no control over explosives procured by the military.
Assessing the power of a bomb involves four factors: VOD or velocity of detonation; strength; sensitivity; weight; and length of storage. Military explosives are normally of high VOD and average 4500m/sec and above. They are not sensitive, compact and heavy weight. The higher the VOD, the more powerful the explosion. The VOD of TNT is around 6,800 metres per second, while the VOD of ANOF or ammonium nitrate is 3000 metres per second. RMX has a VOD of 8000 metres per second.
The methods of activating explosives also vary. They may be victim-operated devices, for example, which can be attached to the door of the victim’s home. When the door is opened, “Boom!”, the bomb explodes. Or, as if often depicted in films, a bomb may be activated when the victim starts his or her car. Explosives may also be activated using a timer or by remote control.
For commercial purposes (mining and cement industries), low explosives are normally used. In the past, NJBS, a type of nitroglycerine, was commonly used. Use of this explosive was discontinued because it is highly sensitive, and it was replaced by Na4No3 or ammonium nitrate. Commercial explosives are generally low explosives and are made from inorganic nitrates such as ammonium or sodium nitrate, and more recently from organic nitrates (EGDN), nitratimines, nitroacromatic compund (TNT) and chlorates and perchlorates (potassium percholrate). Explosives used in military operations include TNT (trinitrotuleune), PETN (pentaerytritol tetranitrate), RDX (formula development X) and Semtex (semtim explosive).
In the Indonesian National Forces, TNT is used in training and war. In training, only 160 grams is allocated to each unit, to produce a sound effect. In war, TNT is used to destroy bridges and other buildings.