Radiation Protection Glossary

A radiation protection glossary for Radiation Protection Supervisors (RPS), Radiation Protection Advisers (RPA) and anyone else interesting in radiation safety terms and definitions. The glossary is a mixture of health physics , phrases related to radiation protection legislation, transport, practical safety, technical terms and similar.

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U

    Unsealed Source

    With respect to Radiation Protection, an unsealed source is is a source of Ionising Radiation in the form of Radioactive material which is not encapsulated or otherwise contained. The implication is that unsealed radioactive material can move around and if uncontrolled would lead to Contamination. It should be noted that unsealed sources are used extensively in biological research and medicine. See Open Source for a related definition, and Sealed or Closed Source for alternative types. For a more detailed explanation please head over to the following Ionactive technical guidance: What is the difference between sealed and unsealed radioactive source?

    Uranium

    Uranium is a heavy, metallic, naturally Radioactive Element of Atomic Number 92. It has two principle isotopes of uranium-235 and uranium-238 (and very small quantities of Uranium-234). The proportions of natural uranium by weight are about 0.01% Uranium-234, 0.072% Uranium-235, and 99.27% U-238. Uranium-235 is used in the the nuclear industry because it is fissionable by Thermal Neutrons . Natural uranium is extracted from uranium ore where it starts life as a processed uranium oxide (Yellow Cake). Following this the uranium will undergo a process of enrichment where the concentration of U-235 is increased. A byproduct of this process is depleted uranium which can be used for radiation shielding due to its high density.

The ultimate paradox, of course, is that even though we're all going to die, we've all got to live in the meantime…

– Brian Cox -