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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Actinides are a transition group between actinium and lawrencium (inclusive). The group includes actinium, thorium , protactinium , uranium , neptunium , plutonium , americium , curium , californium etc. The members of the group are called actinides after the first in the series and they are all radioactive. Of the group, only thorium, uranium, plutonium, americium and californium are significant as the others are only produced artificially and have a relatively short Half-Life. The radiologically significant members all have much longer half-life's (e.g. plutonium-239 is in excess of 24,000 years) and are all Alpha Emitters. This means they have the potential to cause a significant Internal Radiation hazard through Inhalation and Ingestion.

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