Japan has in recent years further strengthened its supervision of nuclear and radiation safety under the leadership of an independent and effective national regulator established after the Fukushima Daiichi accident 15 years ago, an International Atomic Energy Agency (IAEA) team of experts said Friday.
The team also provided recommendations on how Japan – which has re-started several reactors that were shut down after the accident in March 2011 – can take steps to additionally enhance regulatory performance in the nuclear field. These include measures to help maintain specialised regulatory expertise through more flexible staff recruitment.
The Integrated Regulatory Review Service (IRRS) mission was conducted at the request of the Government of Japan and hosted by the Nuclear Regulation Authority (NRA). The IRRS team completed its two-week mission on 6 February.
With 1,080 employees and 22 regional offices, the NRA was set up in 2012 as a key part of Japan’s efforts to improve nuclear and radiation safety. The previous IRRS mission to Japan was carried out in 2020, as a follow-up to an initial review in 2016.
“Since the last mission, Japan has further strengthened its regulatory framework. We observed a highly independent regulator with clear leadership and a strong focus on safety as well as on regulatory effectiveness and efficiency, underpinned by transparent decision‑making,” said IRRS team leader Petteri Tiippana, Director General of Finland’s Radiation and Nuclear Safety Authority (STUK).
Before the Fukushima Daiichi accident, Japan’s 54 nuclear power reactors produced about 30 per cent of its electricity. They were all shut down because of the accident, but 14 reactors have resumed operations after conforming to new safety requirements. The country also has fuel cycle facilities, research reactors and widely uses nuclear and radiological applications in industry, hospitals and other fields.
Using IAEA safety standards and taking advantage of international good practices, IRRS missions are designed to strengthen the effectiveness of the national regulatory infrastructure, while recognizing the responsibility of each country to ensure nuclear and radiation safety.
The IRRS team comprised 18 senior regulatory experts from 17 IAEA Member States: Argentina, Australia, Brazil, Finland, France, Germany, Hungary, India, Italy, Lithuania, Netherlands, Pakistan, Portugal, Romania, Spain, Switzerland, and the United States. The mission team also included five IAEA staff members.
They reviewed all regulatory areas, except for control of medical exposure, including: responsibilities and functions of the government and of the regulatory body; emergency preparedness and response; nuclear power plants; research reactors; nuclear fuel cycle facilities; radiation sources; radioactive waste management facilities; decommissioning; transport of radioactive material; occupational exposure; public exposure control; and interfaces with nuclear security.
The experts also conducted interviews and discussions with NRA staff and observed regulatory oversight activities at a nuclear power plant, a research reactor, a nuclear fuel cycle facility, radiation sources facilities, and a decommissioning facility.
The team said the holding of joint review meetings with all nuclear operators to share and discuss the results of the NRA’s evaluation of emergency preparedness and response exercises was a good practice that could serve as a model globally.
The experts also identified several good performances, including new regulatory requirements regarding ageing and long-term management, and the development of a national strategic plan that supports the long-term availability of qualified personnel across the nuclear sector.
Recommendations and suggestions for further improvement of Japan’s regulatory system included:
Prior to the IRRS mission, the NRA conducted a self-assessment that “set a clear direction” for the team’s work, said team leader Tiippana: “Our mission confirmed and refined it. We think that the biggest gains will come from more proportionate and predictable oversight, long lasting specialist expertise, and pairing Japan’s exemplary openness with formats that enable frank, in depth technical dialogue with other stakeholders in the country’s nuclear sector”
IAEA Deputy Director General Karine Herviou, Head of the Department of Nuclear Safety and Security, said Japan was demonstrating “a commendable commitment” to nuclear and radiation safety by inviting and hosting the mission.
“The NRA has come a long way since it was founded just 14 years ago, firmly establishing itself as a robustly independent regulator,” said Herviou. “Improving nuclear safety is a never-ending task and I’m confident that Japan will continue on this path.”
NRA Chairperson Shinsuke Yamanaka said: “The NRA has made progress in steadily implementing and continuously improving nuclear and radiation regulation. This IRRS mission was an invaluable opportunity to receive observations from international experts of nuclear and radiation safety. We will promptly apply the recommendations and suggestions from the mission to improve our regulatory activities.”
The final mission report will be provided to the Government of Japan in about three months. The Government plans to make the report public.
