Radiation Protection Glossary

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

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Also known as Radioactive Decay. Radioactive substances undergo radioactive decay, the rate of which is determined by the properties of the radionuclide. As decay proceeds the resulting activity of the parent Nuclide reduces and will eventually disappear. The daughter product may be stable (inactive) or may itself be Radioactive and undergo further decay (i.e. as part of a decay series). The rate of decay can be expressed in terms of its Half-Life (the time taken for the activity to reduce by half).

The definition of 'safe' is not strictly an engineering term; it's a societal term. Does it mean absolutely no loss of life? Does it mean absolutely no contamination with radiation? What exactly does 'safe' mean?

– Henry Petroski