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There are three main types of explosions: chemical, mechanical and nuclear. Each type of explosion can be equally devastating and serious, causing unprecedented harm to the surrounding people, atmosphere and infrastructure. Therefore, understanding different types of explosions and how they occur is important.

An explosive substance or device has the potential to produce a large amount of energy quickly, reaching extremely high temperatures. This vast amount of energy occurs due to reactions that take place in explosive materials which can be chemical, mechanical or nuclear.

The different types of explosions are:

Chemical: Chemical explosions occur due to either decomposition or combination reactions, which are both exothermic reactions. Consequently, the rapid expansion of gas which is released forms a shock wave. There are two types of chemical explosives: High-Order Explosives and Low-Order Explosives.

High-Order Explosives: These explosives cause destructive shock waves, such as dynamite.

Low-Order Explosives: These explosives lack the over-pressurization wave which high-order explosives, such as gunpowder, create.

Mechanical: A mechanical explosion requires a physical reaction which is neither chemical nor nuclear. Mechanical explosions involve a high-pressure gas within a container expanding beyond the limit of a container’s tensile strength, resulting in the container bursting open to release the pressure. This release of contents from a container creates a shock wave. If the material which is stored in that container is flammable, a fire will ignite.

Nuclear: A nuclear explosion occurs due to either a fusion or fission reaction, which releases a large amount of heat and gas very quickly. The energy which is released heats the surrounding air and creates a blast wave. Regarding nuclear bombs, fusion and fission reactions are used within these.

Nuclear explosions release radiation and radioactive debris which can be seriously harmful to those in the surrounding area. Nuclear explosions can therefore be organised intentionally to cause harm and destruction to those in the surrounding area.

To date, there have only been two nuclear weapons deployed in combat, which were both launched by the United States against Japan during World War II. In August 1945, the United States dropped an atomic bomb on Hiroshima, creating a huge explosion which killed approximately 80,000 people initially and destroyed 13 square kilometres. The huge quantity of energy released from the bomb managed to wipe out 90% of the city.

Subsequently, the United States dropped an atomic bomb on Nagasaki, creating another deadly explosion which killed up to 40,00 people initially. In both instances many died immediately, but there have been a huge number of deaths since due to the long-term effects of radiation.

The suffering of this horrific nuclear explosion continues to affect citizens physically and mentally today, and demonstrates the truly devastating and immeasurable impact that explosions have on those who sadly suffer them. Therefore, understanding the different types of explosions is important.

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