Page:Survival Under Atomic Attack.djvu/10

 The injury range of the explosive radioactivity from a modern A-bomb is a little over 1 mile, if the bomb is exploded about 2,000 feet in the air.

If it is exploded much higher, some of the radiation may not reach the ground, so the range may be less. If it is exploded much lower, the radiation also may not reach out as far, because it would be blocked by the ground or by buildings.

A little more than a mile away, the principal effects of the few dying rays that struck you could be seen only as temporary blood changes in a doctor's examination. You probably wouldn't even realize you had been exposed.

A little less than a mile from the explosion center, if you are unprotected, you are almost sure to suffer illness. Less than two-thirds of a mile away, those caught in the open are pretty sure to soak up a fatal dose of radioactivity.

Still, the possibility of your being caught without some protection is not very great. Even if you are on the street, there is a good chance that a building, or many buildings, will be between you and the burst, and they will partially or completely shield you.

Atomic explosions high above ground cause the most widespread damage. And, as happened in Japan, when an A-bomb goes off in the air you are

far more likely to be hurt by the bomb's blast and heat waves than by its radioactivity. At Hiroshima and Nagasaki slightly over one-half o£ all deaths and injuries were caused by blast. Nearly one-third of the casualties were from the heat flash. 10