On 16 December 2011, IAEA Director General Yukiya Amano issued the following statement:
“The IAEA welcomes the announcement by the Government of Japan that the reactors at Fukushima Daiichi Nuclear Power Station have achieved a ‘cold shutdown condition’ and are in a stable state, and that the release of radioactive materials is under control.”
“Overall TEPCO and the Japanese Government have made significant progress and have completed the second step of the TEPCO’s roadmap by the end of the year as they had planned.”
“The IAEA is continuing to monitor the status of the Fukushima Daiichi Nuclear Power Station and the radiological situation in Japan following the earthquake and tsunami of 11 March. The IAEA receives information updates from a variety of official Japanese sources, through the national competent authorities. The Agency continues to stand ready to provide necessary assistance to Japan as requested.”
Cold shutdown conditions are reached when three conditions have been established: the reactor pressure vessel’s temperature is less than 100 degrees Celsius, the release of radioactive materials from the primary containment vessel is under control and public radiation exposure by additional release is being significantly held down.