Lessons Learned from Fukushima Nuclear Accident: Human Aspects Still Need Work

“The one thing that is most difficult to enhance is one of the most important components of a nuclear power plant and that is the people,” said William D. Magwood IV, director-general of the Organisation for Economic Co-operation and Development’s Nuclear Energy Agency (NEA).

Magwood’s comment came during a February 29 press conference releasing the NEA’s report entitled “Five Years after the Fukushima Daiichi Accident: Nuclear Safety Improvements and Lessons Learnt.”

Steps in the Right Direction

The report focuses on the actions undertaken by the NEA and its member countries at the national and international levels to improve nuclear safety and to implement the lessons learned from the March 2011 accident. It also offers a series of conclusions and identifies some of the challenges that remain.

When asked what he felt was the single most important improvement implemented by NEA member country fleets as a result of Fukushima, Magwood pointed to the institution of flexible, mobile power systems and cooling equipment.

“This provides the capability for plants to respond to events that have not been considered. If there is an event of any type that challenges the ability of a nuclear power plant to maintain core cooling, the equipment that has been provided at nuclear plants around the world is such that whatever circumstances develop on the nuclear plant site, it is now possible to respond positively and to avoid damage to the core and to avoid problems in the spent fuel pools,” Magwood said.

He added that the training provided with the equipment allows nuclear operators to respond to the unexpected better than could have been imagined five years ago.

“Nuclear plants around the world have flexible approaches to dealing with a wide range of possible accident scenarios to prevent the worst from happening,” he said.

Some other examples of safety enhancements enacted since the accident include:

• Reassessing external hazards
• Reinforcing flood protection measures
• Increasing the robustness of electrical power supplies
• Adding provisions for sufficient battery capacity
• Improving training for severe accident management
• Implementing filtered vents and filtering strategies
• Reinforcing the principle of regulatory independence
• Considering safety culture characteristics and organizational factors in decision-making processes

Room for Improvement

Although positive steps have been taken, there is still more to be done. Magwood noted that the three most prominent nuclear accidents in history—Three Mile Island, Chernobyl, and Fukushima—all had very important human aspects.

“I think that over the next five to 10 years you will most likely see a greater effort in dealing with the people aspect of operating nuclear power plants—assuring that safety culture is satisfactory, assuring that organizations can make good decisions, assuring that the training is in place. These are easy words to say, but in many cases, very complicated to implement, and we have seen this over and over again,” Magwood said.

“So if we are going to prevent these things from happening in the future, we have to become better at dealing with the human element, and I think you are going to see that become a greater and greater part of the conversation globally as we go forward,” he added.

Some other conclusions from the report include:

• Safety is ensured through a continual process, which includes operating experience and research.
• The principle of regulatory independence is fundamental and requires vigilance to ensure it is maintained.
• Unique natural conditions exist in member countries and not all are starting from the same point, so while the outcomes sought are very similar, there are differences in how countries pursue the goal of enhancing safety and preventing and mitigating potential accidents.
• Operating experience combined with risk insights can provide a source of potential improvement, as demonstrated in the course of real events.
• Research continues into accident progression, recovery, and the human factors involved in severe accident response.
• The resources needed to manage an emergency on the scale of the Fukushima accident are considerable.
• Involvement of stakeholders, such as local authorities, industry, nongovernmental organizations, government officials, and the public in decision-making is appropriate and advisable to enhance the credibility, legitimacy, sustainability, and final quality of regulatory and off-site emergency management decisions.
• International cooperation provides a forum for regulators to work together to share and analyze data and experiences, gain consensus, and develop approaches that can be applied within each country’s regulatory process.

For more on Fukushima and actions being taken as a result of the accident, see “Three Years After Fukushima in Four Infographics,” “Four Years After Fukushima,” and “Fukushima Mitigation Strategies: Is Progress Being Made at U.S. Nuclear Plants?”

—Aaron Larson, associate editor (@AaronL_Power, @POWERmagazine)