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Name: Ed
Status: other
Grade: 9-12
Country: Canada
Date: April 4, 2011

Can you compare the radiation released in a nuclear bomb air blast with the radiation released by power plant melt down?

Hi Ed,

First off, the term "meltdown" tends to be a sensational term used in the media. In reality, it simply means that the fuel rods in a reactor have partially or fully melted. A reactor that has had a meltdown does not necessarily have to release any significant radioactivity at all. For example, the Three Mile Island reactor in the US suffered a partial meltdown, but no significant radioactivity was released.

Even at its worst, there is no comparison between the radioactivity and damage caused by a reactor suffering a meltdown, and the radioactivity released by, and extreme damage resulting from, a nuclear explosion. To illustrate, one only need compare the extreme damage and massive casualties resulting from the very small nuclear bomb dropped on Hiroshima, with the lack of any civilian casualties whatsoever caused by the Three Mile Island event.

Regards, Bob Wilson

As you might expect, the answer depends on what sort of a bomb and what sort of a reactor you are comparing, because the amounts of nuclear radiation released vary over a huge range. A nuclear bomb releases all of its radioactive material into the environment. If it is detonated close to the ground, it produces even more radioactive material by irradiating large amounts of dirt and spewing the newly radioactive dirt all over the place. If both contained the same amount of radioactive material, a bomb would be much, much worse than a reactor, because most of the radioactive material in a reactor will not be widely dispersed even in a complete meltdown. However, a nuclear reactor contains a lot of radioactive material, and typically it also contains several reactor loads of "spent" fuel, in a cooling pool, which might also be dispersed into the environment in a worst-case accident.

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