Regulators must learn from each other, says head of ASN

24 March 2021

Nuclear regulation requires "humbleness and openness", Olivier Gupta, Director-General of France's nuclear safety regulator, told OECD Nuclear Energy Agency Director General William Magwood in a WebChat yesterday. Gupta has been Director-General of the Autorité de Sûreté Nucléaire (ASN) since 2016 and has been chair of Western European Nuclear Regulators Association (WENRA) since 2019.

ASN Director-General Olivier Gupta

"We are working on issues for which we should never rely on certainties and this has to do with a questioning attitude, which is one of the bases of safety culture," Gupta said. "We have to expect to be challenged, and again it has to do with openness, and that's also a reason why I very much like having international exchanges. I think they too are a cornerstone of nuclear safety. Even if you belong to an advanced nuclear country, then you are prepared to change your practices, your regulations, if you identify a better practice, a better way to regulate, in another country."

Magwood asked whether it is part of ASN's role to instill such humbleness in operators as well. Gupta said licensees and operators themselves, inside their own organisations, must have this same kind of questioning attitude and openness to what's happening abroad. "That's an essential part of nuclear safety and we have to check that as regulators."

The public often perceive regulators as having an enforcement role, he said, but actually their primary function with licensees is influence. "I often like to say that, as regulators, we have the licensees we deserve. For myself, I want licensees that fully meet their responsibilities in terms of safety. And that's one of the reasons we have, at least in France, regulation that is objective-based rather than means-oriented and prescriptive." This shows licensees that they should not wait for the regulator to tell them what they should do; they should know what is necessary to ensure a good level of nuclear safety. "They are not there to please us," he said.

Performance assessments of licensees should not simply be based on the number events that has been reported, he said. "On the contrary, I will consider that the number of events at each plant is more a measure of the transparency of the plant than of the safety level of the plant."

In order to best communicate the concept of risk to the general public when explaining the basis of regulatory decisions, Gupta said regulators need to make complicated matters easier to understand. "We are dealing with difficult issues and nuclear safety is very complex. The first thing is being able to explain it in simple words, words that are understandable by the stakeholders."

Different national approaches

Magwood asked Gupta whether he sees significant differences in how ASN approaches safety issues with regulators in other countries. There is "a very wide convergence on most major issues", he replied, thanks to existing international frameworks and longstanding relationships.

There are differences however in safety objectives for long-term operation, especially between the USA and Europe, he said, such as in the debate on whether safety should merely be maintained or if it should be improved at plants planning to operate beyond 40 years or more. Another example he gave was the way probabilistic safety assessments (PSA) are used. "Regulators tend to ask for more evidence than just the results of the PSA."

There are also differences in the way the International Nuclear Event Scale (INES) is used. "We have this scale that is internationally shared but not used in exactly the same way in various countries. If you look at the number of events that are declared in large countries, it should be roughly the same - it should be proportional to the number of power plants. There is no reason why there should be more incidents in such-and-such country," he said.

Magwood asked if "stark" differences in the approaches of major regulators can lead to a decline in public confidence. "At least in France, I don't see many questions from the public," Gupta replied. "We sometimes have questions from the licensees."

Harmonising approaches

There has been a real effort towards common standards and approaches in nuclear safety, particularly since the Fukushima Daiichi accident. Magwood noted, to which Gupta replied: "The safety reference levels are the tools that have been developed by WENRA as a basis for harmonisation in Europe."

These safety reference levels are based on the International Atomic Energy Agency's (IAEA) Safety Standards. WENRA selected from these standards the items that were most relevant to harmonisation in Europe. In addition, it added some of the European best practices to the IAEA standards.

"On the basis of these safety reference levels, we have harmonised our national safety regulations on a voluntary basis," Gupta said. "I think we can be quite proud of the result because we are there now. We have harmonised regulations all over Europe thanks to this instrument. I think it is quite an achievement."

Asked if he would support the development of an international mechanism to monitor the independence of nuclear regulators, he said there are already international mechanisms through which regulators report their individual statuses. "We have the conventions and the IAEA," he said. "We have to recognise that independence of the regulator, even in advanced nuclear countries, did not happen overnight. It took a long time."

Preparing for new technologies

Magwood asked how prepared the ASN is for regulating new technologies, such as small modular reactors (SMRs) and fourth-generation reactors.

"We have one project from the French nuclear industry, called the Nuward, with several partners," Gupta said. The Nuward design - with a capacity of 300-400 MWe - was announced in September 2019 by the French Alternative Energies & Atomic Energy Commission, EDF, Naval Group and TechnicAtome. It was jointly developed using France's experience in pressurised water reactors. The partners aim to complete the basic design of the Nuward between 2022 and 2025.

"It is at the stage of preliminary design studies and we are engaging with the industry," Gupta said. "We are starting discussions with them. ASN has also been involved in several international fora and this is very useful for us to gain experience and insights from foreign counterparts.

"We have the opportunity in France to have an objective-based regulation, which is not very prescriptive, so I don't see any obstacle in French regulation to the development of new technologies, such as SMRs. Our system ... really relies on an in-depth technical dialogue with the industry. So this leaves plenty of possibilities for new technologies and innovations."

Researched and written by World Nuclear News