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. 

Lead

With respect to Radiation Protection, lead together with perhaps concrete, is the most likely shielding material for attenuating X-Rays and Gamma Rays. It has a density approximately 11 times greater than that of water and is easily formed into sheets and interlocking bricks. For example, 4 cm lead will attenuate Co-60 gamma rays to 1/10th of the unshielded value (ignoring geometric and beam effects).

Atoms are very special: they like certain particular partners, certain particular directions, and so on. It is the job of physics to analyze why each one wants what it wants.

– Richard P. Feynman -