The aim of the DEFOR (Debris Bed Formation) program is clarification of the phenomena that govern formation of the debris bed in different scenarios of corium melt release into a deep water pool and quantification of the debris bed properties related to coolability.

  • RECI

    The aim of the RECI (RECombiner & Iodine) program was to quantify the iodide → iodine conversion in realistic conditions of recombiner operation, albeit under the following constraints: the experiments were to be performed with non-radioactive substances, and without hydrogen.


    The test section of the facility consists of a scaled-down model of VVER-440 steam generator, which has a bundle of 38 tubes with inlet and outlet chambers (hot and cold chamber, respectively), and a secondary side with the steam outlet line but without droplet separators and steam dryers.

  • SFRD

    Short fuel rod experiments were carried out in the framework of the EU 5FWP COLOSS Project. The simultaneous dissolution of UO2 pellets and ZrO2 by molten Zr was investigated with PWR and VVER samples.


    The PWR PACTEL test facility is designed and constructed in 2009 to be used in the safety studies related to thermal hydraulics of pressurized water reactors with EPR type vertical steam generators


    The MISTRA facility is a steel cylindrical vessel with a top flat cap and a curved bottom. The internal volume is 99.5m3, the internal diameter - 4.25m, the height - 7.4m. The vessel is thermally insulated, but the wall temperature is not controlled.


    The VERCORS programme, which involves tests with short fuel-rod samples, has proved to be a rich source of information regarding FP release and tranport.

  • PAKS

    The OECD-IAEA Paks Fuel Project aimed to support the understanding of fuel behaviour in accident conditions on the basis of analyses of the Paks-2 event. Numerical simulation of the most relevant aspects of the event and comparison of the calculation results with the available information was carried out between 2006 and 2007.


    This facility comprises a water supply pipe, a quartz test section (110, 180 or 290 mm diameter) in which the debris bed is placed, together with its instrumentation, and a steam relief pipe. It is used to conduct refl ooding tests by means of injecting water onto a bed of metal particles heated by induction.

  • ISTP

    This programme sets out to reduce uncertainties when evaluating the environmental release of radioactive products such as iodine or ruthenium following a core meltdown accident in a pressurised water reactor (PWR).


    The TOSQAN experimental vessel is a large stainless steel cylindrical enclosure (volume 7m3, height 4m, internal diameter 1.5m) with double walls. A coolant circulates in between the walls to regulate the wall temperature from 60 °C to 160 °C.

  • LIVE

    Facility consists of the hemispherical test vessel, a volumetric heating system in the test vessel to simulate the decay heat, a heating furnace to generate and pour the simulated corium melt, and a multitude of instrumentation to characterize the status of the melt.


About us

About us

At present time the JRC is engaged in the management of this new version of the STRESA tool to secure the European Union storage for severe accident experimental data and calculations.

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