Complacency contributed to Fukushima accident, says Amano

02 September 2015

Japan considered its nuclear power plants safe and was therefore not prepared for the March 2011 accident at the Fukushima Daiichi plant, International Atomic Energy Agency (IAEA) director general Yukiya Amano has said in a comprehensive report on the accident.

At the IAEA General Conference in September 2012, Amano announced that the agency would prepare a report on the Fukushima Daiichi accident. He stated that this report would be "an authoritative, factual and balanced assessment, addressing the causes and consequences of the accident as well as the lessons learned."

The IAEA has now published that report, which it said is "the result of an extensive international collaborative effort involving five working groups with about 180 experts from 42 Member States with or without nuclear power programs and several international bodies."

"A major factor that contributed to the accident was the widespread assumption in Japan that its nuclear power plants were so safe that an accident of this magnitude was simply unthinkable."

Yukiya Amano
IAEA director general

The report - entitled IAEA Director General's Report on the Fukushima Daiichi Accident - is accompanied by five technical volumes. These give a description and context of the accident; a safety assessment; examines emergency preparedness and response; radiological consequences; and, post-accident recovery.

In the foreword to his report, Amano states: "A major factor that contributed to the accident was the widespread assumption in Japan that its nuclear power plants were so safe that an accident of this magnitude was simply unthinkable. This assumption was accepted by nuclear power plant operators and was not challenged by regulators or by the government. As a result, Japan was not sufficiently prepared for a severe nuclear accident in March 2011."

He noted that the possibility of an accident involving more than one reactor at the same site and at the same time was not considered. Amano also said that insufficient provision was made for the possibility of a nuclear accident occurring at the same time as a major natural disaster.

Amano said the accident exposed "certain weaknesses" in Japan's regulatory framework, with responsibilities divided among a number of bodies. He also said there were certain weaknesses "in plant design, in emergency preparedness and response arrangement and in planning for the management of a severe accident".

Since the accident, Japan has reformed its regulatory system "to better meet international standards", while emergency preparedness and response arrangements have also been strengthened, Amano said. Meanwhile, other countries responded to the accident by reassessing the design of their plants and taking steps to strengthen the protection of those plants against extreme external events.

Amano said, "I am confident that the legacy of the Fukushima Daiichi accident will be a sharper focus on nuclear safety everywhere. I have seen improvements in safety measures and procedures in every nuclear power plant that I have visited. There is widespread recognition that everything humanly possible must be done to ensure that no such accident ever happens again." He added, "This is all the more essential as global use of nuclear power is likely to continue to grow in coming decades."

"There can be no grounds for complacency about nuclear safety in any country," Amano stressed. "Some of the factors that contributed to the Fukushima Daiichi accident were not unique to Japan. Continuous questioning and openness to learning from experience are key to safety culture and are essential for everyone involved in nuclear power."

Amano described his visit to Fukushima Daiichi a few months after the accident as a "shocking and sobering experience". He said he was "deeply impressed by the courage and dedication" of the workers who struggled to bring the damaged reactors there under control. "They deserve our respect and admiration," Amano said.

Researched and written
by World Nuclear News