Design considerations for severe accident containment performance

Containment designs for current light water reactors are based on conservative design bases which have resulted in structures that are very rugged with substantial margins to failure. For future advanced light water reactors (ALWRs), severe accident concerns must be considered in addition to the traditional design bases when designing containment structures. Although new, prescriptive regulations for severe accident design bases are not necessary, acceptance criteria for the resolution of severe accident concerns must be established in a timely manner to support the development of these ALWRs. This paper suggests an approach to developing such acceptance criteria and identifies the major severe accident technical issues which need to be resolved for future containment designs. (orig.)