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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For formal advice, see our Radiation Protection Adviser pages. 

Half-Life (Biological)

The biological half-life is the time taken for half of a radioactive material, (present in a body as a result of inhalation, ingestion, injection or absorption), to be eliminated by the biological processes in that body. For example, Tritium contaminated ingested water will tend to clear quickly (quicker still if the individual drinks plenty of water), whereas Ca-45 will tend to bind to bone. The solubility of the radioactive substance will also effect retention time in the body.

In radiation protection I spend most of my time explaining to clients what they do not need to worry about.

– Mark Ramsay -