The heat blast from the explosion is very powerful; up close, it can cause 3rd degree burns and even death. As the heat travels from the center of the explosion, it gets weaker. The heat can affect people many miles from the explosion.

The shock wave is most damaging at the site of the explosion. It acts like a very strong, very fast wind. Close to the explosion, it can topple skyscrapers and overturn vehicles. People are injured or killed when buildings collapse. The effect gets weaker the farther the shock wave travels from the center of the blast. The shock wave can be felt many miles from the explosion.

The area close to the blast will be hit by powerful gamma rays. These gamma rays don't travel very far before becoming too weak to be dangerous. When living organisms are hit by gamma ray radiation, the effects can be harmful or fatal.

The explosion sucks up bits of the ground around the bomb, carries them high into the air, blasts them into tiny particles and irradiates them. These particles can be carried hundreds, or even thousands of miles, as they slowly drift down to earth in a a "fallout cloud." Where the cloud passes and lands, it showers radioactivity. Exposure to uncontrolled radioactivity can be harmful to living organisms. Because winds are very unpredictable, the fallout information shown here is based upon the average winds. Small changes in the wind can cause large changes in the results.

* = The average fallout received in a one month period following the blasts. Certain areas may receive more or less depending on winds and other factors.