Radiation is energy in motion in the form of waves or streams of particles. There are many kinds of radiation all around us including ultraviolet radiation, which produces a suntan, infrared radiation, which is a form of heat energy, and radio and television communication signals.

When most people hear the word radiation, they often think of atomic energy, nuclear power, and radioactivity. The energy in this kind of radiation can cause changes in atoms, creating electrically charged atoms which we call ions. Radiation which produces ions is called ionizing radiation.

All radiation is not equally hazardous, and it is important to distinguish between different types of radiation that are used in research at UBC to ensure that proper precautions are taken.

Alpha radiation

Alpha particles consist of two protons and two neutrons, and carry a positive charge. Alpha particles are barely able to penetrate skin and can be stopped completely by a sheet of paper.

Beta radiation

Beta radiation consists of fast moving electrons ejected from the nucleus of an atom. While more penetrating than alpha radiation, beta radiation is stopped by a book or human tissue.

Gamma radiation

Gamma radiation is a very penetrating type of radiation. It is usually emitted immediately after the ejection of an alpha or beta particle from the nucleus of an atom. It can pass through the human body, but is almost completely absorbed by denser materials such as concrete or lead.

X-rays

X-rays are a form of radiation similar to gamma radiation but produced mainly by artificial means and infrequently by naturally occurring radioactive substances.

Neutrons

Less common, neutron radiation occurs when neutrons are ejected from the nucleus by nuclear fission and other processes. Neutron activation is used to produce radiopharmaceuticals used in medical scanning techniques.