Containment. Enclosures

The nuclear boiler is located in the reactor building. In the event of an accident involving the boiler, radioactive substances may be released, and their containment must be ensured in order to limit radioactive emissions into the atmosphere to acceptable levels.

This containment function is achieved by the wall(s) of the reactor building known as the containment vessel. Various associated systems are also used to limit releases from the containment by bringing the pressure in the vessel down to close to atmospheric pressure after a few hours to a few days. These include, in particular, the containment sprinkler system (EAS) and the core safety injection system (RIS).