What are explosives & what happens when they detonate?

In Insider, Training, Science & Technology By Chris Daniels / December 23, 2016

AMK9 specializes in deploying highly trained explosive detection canine teams in order to mitigate risk exposure our clients face around the world. Our canine teams performed on average 4.3 million searches annually and since 2012 have successfully found over 1014 explosive items. Many people have seen the aftermath of these explosive devices on the evening news, movies, documentaries, and television shows. These videos and still images display the power and destruction these devices deliver. In order to provide a greater understanding of what takes place during one of these attacks one must first gain a deeper understanding of explosives.

What is an explosive substance?

An explosive is a substance or mixture of substances which may be made to undergo a rapid chemical change without an outside supply of oxygen. These substance can be broken down to two sub-categories - High and Low Explosives: 

  • High Explosives normally detonate rather than deflagrate or burn; that is, the rate of the reaction into the unreacted material exceeds the velocity of sound.
  • Low Explosives deflagrate or burn rather than detonate; that is, the rate of the reaction into the unreacted material is less than the velocity of sound.

Explosive Categories

The two  sub-categories of explosive substances are comprised of three types: Commercial Explosives, Military Explosives, and Homemade Explosives (HME).

  • Commercial Explosives are manufactured to meet the needs for mining, construction, quarrying, and seismic exploration.
  • Military Explosives are manufactured for maximization of damaging effects. They have a long shelf life, are relatively stable, and have a high-degree of standardization.
  • Homemade Explosives are explosives which can be created by almost anyone and made from common household chemicals that are easily accessible and can be purchased legally.

What is an explosion?

An explosion is the rapid and violent release of energy. This takes place either by a chemical reaction or change of state which is effected in an exceedingly short span of time. The explosion will generate high temperatures and large quantities of gas.

Explosive Initiation is initiated by the application of energy. Common methods of initiation are:

  • Heat - A hot wire as in an electric blasting cap, an electric current, direct flame, friction, or excessive temperature.
  • Shock - High explosives frequently require a severe shock to induce their explosion. One example of severe shock is a blasting cap.
  • Influence - A detonation of one explosive mass that detonates another, without actual contact. Known as a “sympathetic detonation”.

Types of Explosions

There are three types of explosions: Mechanical, Chemical, and Nuclear.

  • Mechanical explosions take place when the pressure inside a container overcomes the strength of that container, causing it to rupture. An example of this is the over-inflation of a toy balloon.
  • Chemical explosion occurs due to a chemical reaction or change of state in a mixture, when acted upon by an initiating force. The chemical converts to gases, releasing energy in the form of heat and pressure. A container is not required.
  • Nuclear explosions are created by the splitting of an atom or by fusing atoms together.  Energy is released in the form of heat and pressure. 

What happens?

The next topic is one of the most concerning areas for most people. When an explosion takes place, what are the explosive effects or what happens?

  • Shock Wave: Caused by the compression of air being pushed away from the point of detonation and rushing to fill the void. Earth shock is felt below ground.
  • Blast Effect: Caused by the conversion of the explosives into gases with the release of energy.
  • Fragmentation Effect: Fragmentation will vary depending on the type of explosive and container used in relation to the surrounding area. Primary fragmentation is that which is directly associated with the device, whereas secondary fragmentation is found from the environment surrounding the device. An example of secondary fragmentation is loose gravel laying near the device.
  • Incendiary Effect: Thermal heat is produced at the point of detonation at the precise time of detonation. Thermal heat can reach as high as 6000 degrees F.
  • Radiation Effect: Only found in nuclear material and nuclear weapons. May consist of particles as well as ray type, from initial radiation and fallout.

The AMK9 team is proud to have boots and paws on the ground all over the world working relentlessly to protect our clients by detecting explosive materials. Our canines are imprinted, conditioned, and trained to detect a multitude of explosive compounds/materials. Our team works diligently every day to make the world a safer place.