Survey of the state of the art in mitigation systems

The state of the art is reviewed for devices and systems intended to prevent failure of reactor containment structures during severe accidents involving melting of the core. The devices are grouped according to the function they provide, such as core retention, hydrogen control, vent systems, heat removal, etc. Each of the five major types of US containment is then reviewed as to the types and examples of mitigation devices suitable for its special conditions.