Modern civilization is inconceivable without electricity. Nuclear energy is one of the main sources of energy nowadays, so it requires a comprehensive research. The nuclear power sector is the most significant in France, Belgium, Finland, Sweden, Switzerland - in those industrial countries where natural energy resources are insufficient. The nuclear power has a significant advantage over the social, health and environmental costs of the fossil fuel use. Nuclear energy is the most concentrated form of energy. Nuclear power plants don't require a lot of space, they don't need a large plot like a wind farm. Nuclear power stations don’t contribute to carbon emissions, so it doesn’t contribute to global warming. Nuclear power is reliable. It doesn't depend on the weather. It has proven to be cost effective almost all over the world. However, nuclear power plants are potentially dangerous objects. That’s why it’s very important to comply with all of the safety requirements. The term "safety of the nuclear plants" is closely related to different types of damage, with possible harmful consequences of the accidents at the nuclear plants