Nuclear energy is one of the most sustainable and clean energies in the world. It has been widely applied for electricity generation since 1954. However, the safety issues are always perceived as the big concerns for nuclear power development. Therefore, level 2 PSA has been developed in order to investigate the accident progression and containment response during the severe accident. Currently, most level 2 PSA studies are very detailed and plant-specific, which makes individual analysis difficult to be studied by other similar type NPPs for safety improvements. In addition, due to the lack of the generic model, a lot of analysis data are difficult to be compared and selected for precursor analysis. Therefore, in this research, a generic level 2 PSA model has been developed in order to better facilitate nuclear risk mitigation management. The common safety features of pressurized water reactors have been compared and summarized among different generations. By comparing with different risk study results, the validity of the model has also been tested. Moreover, considering that level 2 PSA studies may overlook the societal and ethical aspects of the risk, social acceptance and ethical acceptability regarding risk mitigation strategies have been discussed. By developing a new risk governance framework, both technical and non-technical risks are well-integrated so that nuclear risk mitigation management can be continuously optimized.