The European "Severe Accident Phenomenology" (SAP) short course

The European “Severe Accident Phenomenology” (SAP) short course was launched in 2006 under the 6th EURATOM Framework programme in the frame of the European Severe Accident Research Network of Excellence (SARNET). It established the basis for keeping and transmitting the main knowledge about severe accidents (SA) gained after the Chernobyl accident. Since then, a total of ten SAP short courses have been held between 2006 and 2023. The last course was held in Madrid from 19 to 23 June 2023, at ETSII-UPM, in the framework of the SEAKNOT project. It has been co‐organized by UPM (ES), CEA-IRESNE (FR), CIEMAT (ES), University of Pisa (IT) and Jožef Stefan Institute (SI).The program, developed along 30 hours by 13 expert lecturers, covered the following relevant topics: SA in nuclear power plant (NPP) safety; historical SA: TMI-2, Chernobyl and Fukushima-Daiichi; in-vessel core degradation phenomena: early and late phases; early containment failure: direct containment heating (DCH), hydrogen and CO risk; fuel coolant interaction (FCI) and steam explosions; ex-vessel phase, corium spread; molten core concrete interaction (MCCI), coolability; source term: fission product transport in RCS and containment; source term chemistry; SA computer codes & uncertainty quantification; safety assessment (PSA); SA management guides; radiological impact of SA; decommissioning after SA; new design features for SA mitigation in Gen-III NPPs; SA considerations in Small Modular Reactors (SMR); post-Fukushima safety improvements in Spanish NPP.