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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LET is short for Linear Energy Transfer. This quantity actually reflects the linear rate of energy absorption, by the absorbing medium, as the Ionisation event traverses the medium. In simple terms low LET radiation (e.g. Beta Particles) transfer less energy per unit path length than high LET radiation (e.g. Alpha Particles) to absorbing mediums. LET has most use in radiobiology and has the units of KeV/micron.

A man who dares to waste one hour of time has not discovered the value of life

– Charles Darwin -