The Hamaoka Nuclear Power Station, today and tomorrow

HOME>In pursuit of greater safety>Preventing damage to the containment vessel / Controlling the dispersion of radioactive materials

Establishing preparedness in case of severe accidents

The power station is developing preparedness even in the unlikely event of a severe accident including the melting of nuclear fuel.

Preventing damage to the containment vessel

Preventing damage to the containment vessel(image)Measures include installing the facility for cooling the connection with the containment vessel at the top lid1, reinforcing the facility for cooling steam inside the containment vessel2, and installing the facility for cooling heated fuel that has melted and dropped to the bottom of the containment vessel3.

Reactor well water injection system

Alternative spray system for containment vessel

Water injection system for bottom of containment vessel

Controlling the dispersion of radioactive materials

The power station is installing filter vents. When releasing gas into the outside atmosphere to depressurize the containment vessel, the exhaust is fed through a filter that absorbs radioactive materials. This cuts the amount of cesium and other radioactive particles discharged to below one-1000th, thereby preventing large-scale soil contamination and long-term evacuation of local residents.

Preventing the large-scale discharge of airborne radioactive materials(image)

The power station is also installing hydrogen concentration meters and introducing ways of releasing hydrogen from the buildings in order to prevent a hydrogen explosion at the reactor buildings. Water cannons are also deployed to spray water onto the buildings while hydrogen is released, so as to catch and bring airborne radioactive materials onto the ground.

Water cannon(image), Extinguisher training(image)