Question

The main function of shielding in nuclear reactor is provide protection against:
1. α - rays
2. β - rays
3. γ - rays
4. None of these

Answer 1

Correct Answer - Option 3 : γ - rays

Shielding of Nuclear Reactor:

• A nuclear reactor is a prolific source of potentially dangerous nuclear radiation. It is unavoidable since most of the radiation released originates from the fission process itself.
• In addition to the highly energetic neutrons and gamma rays that are emitted simultaneously with the fission event the fission fragments formed are highly radioactive nuclides that emit α and β radiations. The essential shielding problem is the attenuation of the penetrative fast neutrons and high-energy gamma rays that are released in the reactor core and reactor shield.
• The charged particle released, such as α and β radiation, and the heavily ionizing fission fragments are readily stopped within at most few centimeters of dense material so that the charged particle does not penetrate beyond the fuel elements and certainly not beyond the reactor core. 
• The shielding of charged particle radiation is therefore a much less severe problem and shielding is done to protect against highly energetic neutrons and gamma rays.