Explosive material facts for kids

Tet Offensive 1968. A machine gun at USMC Camp Carroll firing on enemy troops.

Explosives are special chemical substances that can cause explosions. When they explode, they burst with a loud sound and change their form very quickly. Think of them like a very unstable material that reacts super fast!

There are two main kinds of explosives: low explosives and high explosives. The difference between them is how fast they explode.

• Low explosives burn very, very quickly. This fast burning is called conflagration. Sometimes, people mix low explosives with high explosives to make them explode.
• High explosives explode with a sudden burst. This is called detonation. They create a lot more pressure than low explosives.

Low explosives are generally safer to use. People use them in things like fuses (which light fireworks), rocket engines, and fireworks. High explosives are used in mining (to break rocks), for demolition (to safely tear down old buildings or bridges), and in military weapons.

Some common low explosives you might have heard of are Gunpowder and ammonium nitrate.

Different Kinds of High Explosives

High explosives can be split into different groups based on how easily they react:

• Primary explosives are super unstable. They react very quickly to even a small shock, friction (rubbing), or heat. Any of these can make them burn or blast right away.
• Secondary explosives are much safer to handle. They don't react as fast to shock, friction, or heat. They might burn if exposed to these, but they won't usually burst or blast on their own. Some people call these "base explosives."
• Tertiary explosives are even more stable. They don't react to shock, friction, or heat at all by themselves. To make them explode, you usually need to mix them with secondary explosives.

Primary explosives are often used as "detonators." This means they are used in tiny amounts to set off the secondary explosives, making them explode.

Examples of primary explosives include mercury fulminate and lead azide. Some well-known secondary explosives are TNT, dynamite, and hexogen.

Safety Markings for Explosives

When explosives are moved from one place to another, their containers have special markings. These markings help people know how dangerous the explosives are. The United Nations has suggested these markings to keep everyone safe.

Here are some examples of what these markings mean:

• 1.1 Mass Explosion Hazard: This means if one explodes, everything else around it might explode too.
• 1.2 Non-mass explosion, fragment-producing: This means it won't cause a huge chain reaction, but it can send out dangerous pieces (fragments) when it explodes.
• 1.3 Mass fire, minor blast or fragment hazard: This means it's more likely to cause a big fire, with only a small blast or a few fragments.
• 1.4 Moderate fire, no blast or fragment: This is for things like consumer fireworks. They might cause a moderate fire but won't blast or send out fragments.
• 1.5 Explosive substance, very insensitive (with a mass explosion hazard): This is an explosive that's hard to set off, but if it does explode, it could cause a mass explosion.
• 1.6 Explosive article, extremely insensitive: This is an explosive that is very, very hard to set off.

Images for kids

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  The Great Western Powder Company of Toledo, Ohio, a company that made explosives, seen in 1905.

See also

In Spanish: Explosivo para niños