ctive substances.
Neutrons are
very penetrating but are not as common in
nature. Neutrons have the capability of
striking the nucleus of another atom and
changing a stable atom into an unstable, and
therefore, radioactive one. Neutrons emitted
in nuclear reactors are contained in the
reactor vessel or shielding and cause the
vessel walls to become radioactive.
Radioactive elements emit these radiations
until they have reached a stable state.
For
- some man-made radioac
- tive materials
this occurs in a few seconds. For othe
- r
elements a small amount can emit ra
- diation
f
- or thousands of years. As they break down
th
- ey turn into other el
- ements.
At g
- round zero, the elements emitting
gamma rays and alpha and beta particles ar
- 72-ton hydraulic press
- e
Europium, Cesi
- um, Cobalt, Stront
- ium and
Plutonium.
S
- ources for information about radiation
are the American Nuclear Society and the
U.S. Nuclear Regulatory Commission.