What are X-rays & Ionizing Radiation?
Everyone knows that x-rays are a type of radiation, but what exactly is radiation?
Radiation is simply energy in motion. As you look at the figure below, there are
many types of radiation that you are already familiar with:
While all these types of radiation have many traits in common (e.g., all travel at the
speed of light) only x-rays and gamma rays have enough energy to cause
ionization
when they interact with the body. So our next question is “What is ionization and
why is it a concern?”
All matter is made up of atoms. Atoms contain a small central nucleus containing
protons, which have electrically positive charges. Orbiting the nucleus are electrons
which are small particles with electrically negative charges. In a neutral atom the
number of positive (+) and negative (-) charges are equal (see the figure below).
When an x-ray or gamma ray is traveling through the human body, it will
sometimes interact with an orbital electron of an atom. During the interaction the
radiation can impart enough energy to the electron to “free” it from the atom. The
