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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Distance, in the context of Radiation Protection, relates to one of the three key principles of protection against External Radiation hazards (i.e. Time, Distance & Shielding). In simple terms, increasing the distance between a static source of Ionising Radiation and the absorbing medium (e.g. a person) will reduce the exposure to that person. For certain defined geometries, (e.g. Point Source), the Inverse Square law can be applied which can be stated as: 'double the distance, quarter the dose'.

Two things are infinite: the universe and human stupidity; and I'm not sure about the universe

– Albert Einstein -