Nuclear safety is the basic requirement for the operation of every nuclear power plant. It is a collection of all technical and organizational measures, which have to secure that fission process of the atoms’ nuclei, which releases radioactivity, stays, under all circumstances, under human control. The basic requirements for nuclear safety are the control over the fission reaction, the capturing of radioactive substances and heat transport.
The safety of a nuclear power plant is primarily secured by barriers, which follow from the design of the plant. Their purpose is to prevent the escaping of radioactive substances into the environment and thus to protect against ionizing radiation. Safety barriers include:
- A chemically stable fuel matrix,
- Metallic zirconium alloy shielding of the fuel,
- The material and thickness of the wall of reactor’s pressure vessel and of the primary circuit components,
- The reinforced concrete containment structure, lined with austenitic materials, whereby a hermetic zone is created that contains the primary circuit components.