Safety classifications for the fusion DEMO plant of Korea

Regulatory requirements and industrial codes and standards are to be compulsory top-tier prerequisites for the design and construction of a power plant with nuclear technologies. As it will take considerable time and substantial amounts of investment to develop that for the fusion power plants, design studies on a fusion DEMO plant will be carried out in parallel with developing its regulatory requirements and codes and standards. To overcome this dilemma, a tentative set of general design criteria and classification criteria that are to be applicable for the design studies of the fusion DEMO plant of Korea (DEMO Plant) are proposed with the vacuum vessel pressure boundary that corresponds to the Reactor Coolant Pressure Boundary of the nuclear power plant. To determine the tentative set, the radiation release to the environment and consequences of the postulated events in DEMO Plant are analyzed with rough approximation assuming the inherent safety of a fusion DEMO reactor. The classification criteria of the tentative set include safety class, electrical class, quality group and seismic category for the components, structures and systems of DEMO Plant. Use of ASME Section III for the design study of DEMO Plant is also proposed to make the best use of the commonalities between DEMO Plant and existing nuclear power plant.