Glossary definition of Ionising Radiation

Ionising Radiation is a form of energy produced from natural and man-made radioactive materials. Examples are alpha particles, gamma rays, x-rays and neutrons. Such radiation may occur naturally, e.g. radioactive radon gas found in certain rocks, or cosmic radiation passing through the atmosphere from outer space.

The high energy of the ionising radiation released from radioactive material can have damaging effects when it passes through the human body, mainly because of the damage it can cause to DNA. High doses can kill or seriously injure those exposed to such radiation. Although the risk is small and difficult to assess, even a low dose of ionising radiation has a chance of causing cancer.

Man-made sources of ionising radiation are used extensively in many industrial applications, as well as for specialist medical treatment. The NRPB monitors and controls the exposure of the UK population to man-made ionising radiation from medical and industrial activity.