the european stress test for nuclear power plants

Safety Objective O3: 


Accidents with core melt 


“WENRA expects new nuclear power plants to be designed, sited, constructed, commissioned and operated with the objectives of:

  • reducing potential radioactive releases to the environment from accidents with core melt, also in the long term, by following the qualitative criteria below: 
  • accidents with core melt which would lead to early or large releases have to be practically eliminated 
  • for accidents with core melt that have not been practically eliminated, design provisions have to be taken so that only limited protective measures in area and time are needed for the public (no permanent relocation, no need for emergency evacuation outside the immediate vicinity of the plant, limited sheltering, no long term restrictions in food consumption) and that sufficient time is available to implement these measures.”85 
This safety goal refers primarily to new plants. As far as it defines the safety goal to mitigate the consequences of accidents with core melt it is partly applied by the current “Stress test“. 

In a “Stress test“ that aims at revealing the residual risk of nuclear power plants, the provisions in the plant to mitigate core melt scenarios should be documented. Then the accident scenarios which lead to an early and/or a large release should have to be identified in order to be able to estimate the potential radiological consequences for the affected public.





85 WENRA: Safety Objectives for New Power Reactors, November 2010. Note: The complete text of the safety objectives (including footnotes) is given in the Annex.