Do you know what to do in case of a fire? Fire safety is very important, and we hope that you have learned what to do if you ever see a fire. If you can call the fire department, that's great, but you should always concentrate on getting to a safe place as quickly as possible first.

Some people may be tempted to try to put out a fire on their own. In most cases, though, it's best to let trained firefighting professionals handle the sometimes-difficult job of putting out a fire. They have special training and know just how to put out every type of fire.

For example, some people might think that every fire can be put out with water. However, there are certain types of fires, such as grease fires in kitchens, which can actually be made worse if water is thrown on them. These types of fires may need to be put out with something else, such as flour or special chemicals found in fire extinguishers.

Of course, not all fires can be put out. Sometimes fires get so large so quickly that it's impossible to fight them with the usual firefighting methods. Forest fires, for example, might quickly spread to such a large area that there aren't enough firefighters in the area to be able to battle them effectively. These large fires often simply need to run their course until they run out of fuel and burn out on their own.

There is another type of fire that is often impossible to put out. Would you believe that there's a small town in Pennsylvania that has been on fire for over 50 years? It's true. The town is Centralia, Pennsylvania, and an underground fire burning in coal seams underlying the town has been burning since 1962 and still burns to this very day!

If you were to visit Centralia today, you wouldn't find much. The entire town was evacuated several decades ago. Only a few diehard residents remain. The empty buildings and lonely streets are the only monument to what happened here and is still happening underground.

If you go to certain areas of the town, you can still find areas where smoke seeps up from deep underground. The ground in these areas is also warm to the touch. Most of the areas of the town are considered unsafe to live in because of fears of toxic gases seeping up from below the ground, as well as worries that large areas will cave in as the fires underground make the ground above unstable.

So how did this fire get started? Centralia sits atop a vast network of underground coal mines. Way back in 1962, the town decided to set the local landfill on fire, so that a bunch of the trash would burn and reduce the amount of space it was taking up in the landfill.

Although they thought they had extinguished the landfill fire, it kept burning deep below the surface of the trash where no one could see. The fire burned downward and eventually went underground where it met a great source of fuel: the leftover mine shafts which still opened up onto veins of anthracite coal.

Anthracite coal is known for burning for long periods of time at extremely hot temperatures. Experts estimate the fires under Centralia could burn at temperatures over 500º F and at depths of over 300 feet deep. In addition to baking the layers of soil above the fires and releasing poisonous fumes into the air, the fires also caused the ground to be extremely unstable in areas, sometimes opening up holes large enough to swallow people or even cars!

Even though 50 years seems like a long time, experts believe the fires under Centralia could burn another 250 years before they exhaust the coal supply that fuels them. So why don't firemen simply put them out? They can't!

The fires are too deep and burn too hot to be fought effectively. Several different firefighting methods were tried over the years, but they all failed. Ultimately, letting the fires burn became an economic decision. It was simply too expensive to try to keep fighting the fires. It was cheaper just to abandon the town.

What you might not realize is that Centralia is an incredibly interesting story, but it's far from unique. Would you believe that scientists believe that there are upwards of 200 or more such underground coal mine fires burning in the United States alone? If you count such fires in other major coal-producing countries, like China and India, underground coal mine fires around the world probably number in the thousands!

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