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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O

    Occupational Exposure

    With respect to Radiation Protection, occupational exposure is an exposure which occurs during work with sources of Ionising Radiation. For example, exposures received from working on a nuclear reactor, in nuclear reprocessing or by a dental nurse taking X-Rays would be classed as Occupational. This is distinct from Medical Exposures which are for the benefit of the patient.

    Open Source

    With respect to Radiation Protection, an open source is a source of Ionising Radiation in the form of Radioactive material which is not encapsulated or otherwise contained. The possibility is that open radioactive material can move around and if uncontrolled would lead to Contamination. If not controlled, this could lead to an intake of radioactive material by inhalation or ingestion. It should be noted that open sources are used extensively in biological research and medicine. See also Unsealed Source.

    Optimisation

    Optimisation can be stated as '..a process or method used to make a system of protection as effective as possible within the given criteria and constraints..'. With respect to Radiation Protection, the ICRP 103 publication states '.consider how best to use resources in reducing radiation risks to individuals and populations ... so far as is reasonably achievable, social and economic factors being taken into account'. This is the basis of the ALARA principle, and the UK ALARP principle (but ALARP does not consider social and economic factors and is developed from Case Law)). Radiation protection uses optimisation to reduce exposures below Dose Limits.

    Over Exposure

    With respect to Radiation Protection, an overexposure means a person who has received an unexpected (non-routine) level of Ionising Radiation exposure above some permitted level (Dose Limits). The overexposure may result in a breach of regulations, but in severe cases adverse health effects or even death (see Deterministic Effects).

Radiation is one of the important factors in evolution. It causes mutation, and some level of mutation is actually good for evolution

– David Grinspoon