Reliability Assessment of Safety-Critical Systems of Nuclear Power Plant using Ordinary Differential Equations and Reachability Graph

•Failure of safety critical systems of nuclear power plants lead to catastrophic disasters.•Petri net is a powerful tool to evaluate the performance and reliability of safety critical systems.•Petri net modelling of safety critical systems containing multiple processing nodes for communication.•The proposed technique is applied to Shutdown System of Nuclear Power Plant.•The technique is able to solve the state space explosion problem.