Reduction of Severe Accident Uncertainties (ROSAU) Project
Joint project

The goal of the Reduction of Severe Accident Uncertainties (ROSAU) Project is to reduce knowledge gaps and uncertainties associated with severe accident progression by performing large-scale tests investigating:

  • spreading of melt in a cavity and the effect of metal content in melt on molten core-concrete interaction;
  • in-core and ex-core debris coolability.

In addition to the experiments, a parallel analytical activity is being carried out to refine and validate models and codes for each test category to form the technical basis for extrapolating the findings from the experiments to plant conditions.

ROSAU Members' area (password protected | reminder)


Belgium, Canada, Czech Republic, France, Japan, Korea, Sweden and United States.

Project period

June 2019-June 2024


EUR 8.6 million