Abstract
Abstract
The ability of systems, structures and components that provide ultimate heat sink, to perform their functions and to ensure the safety of the nuclear power plant with VVER-1200 reactor in the events of external influences that entail the loss of ultimate heat sink is subject of the study. Necessity of consideration of mentioned events was demonstrated by last events occurred on NPPs worldwide in particular in Fukushima-Daiichi accident. Probabilistic model was developed implementing modern methods for assessment of probabilistic safety values using digital software RiskSpectrumPSA. Calculated probabilistic safety values confirm chosen design solutions and possibility of probabilistic safety assessment application for similar tasks.