Shielding

A protective barrier, usually a dense material, which reduces the passage of radiation from radioactive materials to the surroundings.

Any material or obstruction, which absorbs (or attenuates) radiation and thus tends to protect personnel or materials from the effects of a nuclear explosion. A moderately thick layer of any opaque material will provide satisfactory shielding from thermal radiation, but a considerable thickness of material of high density may be needed for nuclear radiation shielding. Electrically continuous housing for a facility, area, or component, attenuates impinging electric and magnetic fields.

See shield.