Protection from Radiation: Shielding Factor
The shielding factor means that the more material placed between an individual and a radiation source, the less exposure that individual will receive due to scattering processes within the material. The intensity of a radiation beam is reduced by absorption.
  • Gamma radiation is most effectively shielded by dense material such as lead.
  • Beta radiation can be shielded by relatively thin amounts of wood or plastic.
  • Alpha radiation can be shielded by virtually any material.
Effect of Shielding Layers On Exposure Rate. Much gamma radiation gets through the first layer of shielding. Each layer of shielding reduces penetration, so that little gets through the fourth layer.