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.

Search the Glossary by either clicking on a letter or typing a keyword into the search box. This glossary is relational so when looking at one term you can click through to other related terms as required.

For formal advice, see our Radiation Protection Adviser pages. 

Classified person

A classified person is a designation given in the UK Ionising Radiations Regulations 2017 (IRR17). A classified person is someone who could be exposed to ionising radiation, through occupational exposure including reasonably foreseeable incidents, who could receive more than the following exposures: 6mSv/year whole body effective dose, 150 mSv/year equivalent dose to the extremities, and 15mSv/year to the lens of the eye. It also specifically applies to an employee who works with a source of ionising radiation where a dose rate could deliver a whole body exposure of 20mSv (or 500 mSv to the extremities or 20 mSv to the lens of the eye) within a few minutes from a reasonably foreseeable event.

Education is what remains after one has forgotten what one has learned in school

– Albert Einstein -