At the Committee on the Safety of Nuclear Installations (CSNI) meeting of June 2002, a proposal for an International Standard Problem on containment integrity (ISP 48) based on the NRC/NUPEC/Sandia test was approved. Objectives were to extend the understanding of capacities of actual containment structures based on results of the recent PCCV model test and other previous research. The ISP was sponsored by the USNRC, and results were made available thanks to NUPEC and to the USNRC. Sandia National Laboratory was contracted to manage the technical aspects of the ISP.
At the end of ISP 48, a workshop was organised in Lyon, France on 6-7 April 2005, hosted by Electricité de France. Its overall objective was to present results obtained by participants in the ISP 48 and to assess the current practices and the state of the art with respect to the calculation of concrete structures under severe accident conditions.