Studies and cross-comparisons of severe accident prevention and mitigation capabilities of a SFR and a GFR

•Core melting prevention and mitigation are compared for SFR and GFR.•Both reactor concepts have been developed at CEA (GFR2400 and ASTRID).•Core melting prevention relies on systems operating under pressure for GFR.•Large thermal inertia of SFR gives them good inherent prevention features.•Gaseous coolant makes unlikely large mechanical energy release for GFR.•Low void worth core and mitigation devices of ASTRID makes unlikely energy release.