LAUSR

Abstract Hydrogen generation and its deflagration or explosion can damage the containment integrity during severe accidents (SAs). In this paper, the total amount of the produced hydrogen during Station Black-Out (SBO), SBO along with Large Break Loss of Coolant Accident (LBLOCA) and SBO along with Small Break Loss of Coolant accident (SBLOCA) for the WWER1000/V446 reactor is estimated by the MELCOR code. Parametric analysis on the SA type, passive safety systems, coating materials of the reactor pressure vessel (RPV), cavity's concrete type and condition is discussed to determine their effects on the H2 production. The obtained results showed that the SBO could produce more H2 (450 kg) compared with other SAs. Passive safety systems increase the amount of the hydrogen production. In addition, CRBR concrete produces low amount of the hydrogen compared with other concrete types.