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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For formal advice, see our Radiation Protection Adviser pages. 

Alpha Particle

A positively charged particle consisting of two Neutrons and two protons which is emitted from Atoms undergoing Alpha Decay. The range of the alpha particle is short (< 1cm in air) and they are easily shielded (stopped by a single sheet of paper). They only present a significant hazard where they enter the body - even the most energetic alpha particles are not able to penetrate the dead outer layers of skin.

Physics is really nothing more than a search for ultimate simplicity, but so far all we have is a kind of elegant messiness

– Bill Bryson -