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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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.

Reality is merely an illusion, albeit a very persistent one

– Albert Einstein -