ABSTRACT
Loss-of-coolant accident (LOCAs) can occur over a period of several minutes to several hours, and at the end of the process, the pressure in the containment building stabilizes between 40 PSI and approximately 60 per Square Inch. During some LOCAs, the water temperature in the vicinity of the steam jets may become high enough that the condensation rates at the steam–water interface fall below those that are needed to readily condense the discharged steam. At the end of the LOCA, most of the water inside of the reactor pressure vessel and the piping system has turned to steam, and this steam will be mixed with the air already in the containment building. The presence of the water reduces the internal volume slightly, and this causes the final pressure to be somewhat higher than it would be if the water could be removed from the building at the end of the LOCA.
