Department of Transportation (DOT)/United Nations (UN) Testing and Classification

r. (The theory) Los Alam
os sci entists devised two desig
ns for an atomic b
omb--one using u

ranium 235 and another using plutonium. The uranium bomb was a simple design and scientists were confident it would work without testing. The plutonium bomb was more complex and worked by compressing the plutonium into a critical mass to sustain a chain reaction. The compression of the plutonium ball was to be accomplished by surrounding it with lense-shaped charges of conventional explosives. They w

ere designed to all explode at the same instant. The force would be directed inward, thus smashing the plutonium from all sides. In an atomic explosion, a chain reaction picks up speed as atoms split, releasing neutrons plus great amounts of energy. The escaping neutrons strike and split more atoms, thus releasing s