Nuclear weapons : Who, what, when, where, how?

The first nuclear weapons were made by the United States, and two of them were used to end the war with Japan en 1945. These bombs, called atom bombs, or "A-bombs" by the press, developed their enormous destructive power through a chain-reaction involving the fission of a few pounds of special material. Carsten M. Haaland is one of America's foremost nuclear weapons authorities. With this "Nuclear Weapons" article Haaland begins a series of five articles. This document starts with a history of the nuclear weapons and its mentioned the development of the hydrogen bomb, the worlwide nuclear weapons in 1990 and the developments in nuclear weapons in the Soviet Union

Underground shelter - How much fallout protection?

The purpose of this article is to show by a single, simple example how effectively ordinary earth can reduce the penetration of gamma radiation into a buried shelter. It is possible, and not beyond reasonable attainment, to have a fallout shelter so well shielded that the radiation levels inside the shelter will be less than ordinary, day-to-day radiation levels, even when the ground above is covered with an extremely heavy pile-up of radioactive falllout. If the radiation intensities at the surface above the shelter are as high as 10,000 R/hr, the radiation intensity in the shelter can be kept bellow 0.01 mR/hr (mR is an abbreviation for "milliroentgen", which is one-thousandth of one roentgen). This low radiation level is equal to the average U.S. natural background radiation level at the earth's surface. The reduction in radiation intensity from 10,000 R/hr at the surface to 0.01 mR/hr at the surface to 0.01 mR/hr in the shelter can be obtained with about 8 ft. of earth above the shelter ceiling and a well-designed extranceway