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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Ionising Radiation

Published: Oct 12, 2018

Ionising radiation can be described in a number of ways - the simplest being that it consists of Gamma Rays, X-rays, Alpha & Beta particles and other heavy Ions which have sufficient energy to cause ionisation in materials through which they interact . A less useful (but correct) definition can be found in the Ionising Radiations Regulations 2017 which states 'means transfer of energy in the form of particles or electromagnetic waves of a wavelength of 100 nanometers or less or a frequency of 3 E15 hertz or more capable of producing ions directly or indirectly'.

The definition of 'safe' is not strictly an engineering term; it's a societal term. Does it mean absolutely no loss of life? Does it mean absolutely no contamination with radiation? What exactly does 'safe' mean?

– Henry Petroski -