Our Industry > Radioactivity & Radiation
Radioactivity & Radiation
Radioactivity
refers to the property of spontaneous emission of particles or
electromagnetic radiation
exhibited by certain materials. This radiation is emitted by
unstable atoms as they undergo a transition to a more stable state;
the transition is called radioactive decay. Unstable atoms
that exist in nature are said to be naturally radioactive. Examples
of radioactive atoms found in nature are carbon-14, potassium-42,
radon-222, uranium-235, uranium-238 and thorium-232. In addition
to naturally occurring radioactive materials, radioactive atoms
can be produced when the nucleus of an atom is made to interact
with
a particle or electromagnetic radiation to form an unstable nucleus;
this is typically done in nuclear reactors and particle accelerators.As
radioactive atoms go through the transition to a stable state they
emit radiation in several forms:
- charged particles (alpha particles, beta particles and positrons)
- uncharged particles (neutrons)
- electromagnetic radiation (gamma rays and x-rays)
Radiation is released naturally from the ground and atmosphere
in all places on Earth. This ‘natural background’ radiation,
which varies considerably from region to region, is part of the
environment to which all human beings are conditioned.
Like many things, radiation can be both beneficial and harmful.
Large doses are dangerous. Abundant evidence indicates that small
doses
are harmless.
The radiation produced within the core of nuclear reactors is
similar to natural radiation but more intense. At nuclear power
plants,
protective shielding isolates this radiation, allowing millions
of people to
live safely nearby.
Typically, the radiation people receive comes 90% from nature
and 10% from medical exposures. Radiation exposure from nuclear
power
is negligible. |