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The vital focus on ever-improving nuclear safety

The following article was written by Marianna Katsaouni, Senior Communications Specialist at the World Association of Nuclear Operators.

  • Publication Name: Nuclear Future
  • Published By: Nuclear Institute, Volume 20 #2
  • Date: March / April 2024
  • Website:

The nuclear industry places its highest priority on the safe and secure construction and operation of power plants and their associated infrastructure. The approach to safety is one of continuous assessment and improvement. As the positivity for nuclear continues to grow at pace, and new technologies come onstream, this area has never been more crucial.

The management and certification of nuclear safety involves a comprehensive set of measures and protocols. These include rigorous standards for both construction and operation of power plants, with every aspect of safety meticulously scrutinised and managed to uphold the highest standards of protection both for workers and for the surrounding environment.

The History of Nuclear Safety

Back in 1957 the United Nations (UN) established the International Atomic Energy Agency (IAEA) in response to growing global interest in harnessing the peaceful uses of nuclear energy for development, while also addressing concerns about nuclear safety, security, and proliferation. To this day, the IAEA provides guidance, technical assistance, and oversight to member states.

However, the Three Mile Island accident in 1979 as well as the accident at the Chernobyl generating station in 1986 highlighted the need for improved safety protocols, emergency response plans, and better communication with the public. These incidents were pivotal for the nuclear industry, serving as both a conclusion and a new beginning, as they starkly illustrated the interconnectedness of nuclear facilities worldwide, highlighting that an incident at one plant reverberates across the entire industry. It was now clear that nuclear operators cannot work in isolation. This realisation prompted leaders of commercial nuclear reactors worldwide to transcend any competitive or geographical boundaries.

As a result, the World Association of Nuclear Operators (WANO) was established in 1989, with the overarching objective is to enhance the safety and reliability of nuclear facilities globally. This is achieved through collaborative efforts aimed at assessing, benchmarking, and continuously improving performance standards. Through mutual support, information exchange, and the adoption of best practices, WANO fosters a culture of cooperation essential for safeguarding the integrity and sustainability of nuclear energy on a global scale. The ‘Good Practice on Plant Maintenance’ guide was first published by WANO in 1990, with its Operating Experience and Peer Review programmes launched alongside to collect key performance data and insights.

Furthering these efforts, the Convention on Nuclear Safety (CNS), a landmark international treaty established in 1994 under IAEA, represents a collective commitment among nations to prioritise safety in the operation of nuclear power plants. The convention establishes several key provisions, including regular review meetings, safety principles, and specific review processes that contracting parties undergo periodically.

Leading the Way

For WANO and the IAEA (and CNS accordingly) transparency, information exchange among participating countries, collaboration and mutual learning are fundamental principles, leading to a collaboration between the two organisations.

Unlike regulatory bodies or national nuclear regulatory commissions, WANO is specifically dedicated to commercial nuclear power plant operators. Its membership consists of operators from around the world who voluntarily collaborate to improve safety performance and operational excellence, thus operating on a principle of industry self-regulation and peer support. Its approach is driven by industry collaboration and voluntary participation fostering a culture of collective responsibility for safety, and it has a broad global reach, with member organisations representing nuclear power plants in over 30 countries.

This international scope enables the exchange of diverse perspectives, experience, and expertise, enriching the collective knowledge base and enhancing safety practices worldwide. In addition to safety, WANO emphasises operational excellence as a key component of nuclear plant performance. By promoting best practices in areas such as operations, maintenance, outage management, and human performance, WANO helps member organisations optimise plant reliability and efficiency while maintaining a strong nuclear safety culture.

Every owner or operator of a commercial nuclear power plant in the world is a member of WANO. There are 120 members worldwide, of which 3 are in the UK. These members collectively have approximately 460 operating nuclear units and 60 units under construction. WANO’s members interact with the association primarily through regional centres in Tokyo, Atlanta, Moscow and Paris, and with offices in London and Shanghai. In this way, it unites a competitive industry into a community of nuclear operators that is cohesive, highly collaborative, and fully committed to safe and reliable nuclear plant operations.

High Standards

The association seeks to set the highest possible standards not only through the services it provides, but also through actively cultivating a sense of community within the nuclear industry. This is done by organising events that bring together its members for knowledge exchange, networking and skill enhancement. The events vary in purpose and scopeand include the Biennial General Meeting (BGM). This involves Chief Executive Officers and senior nuclear executives from around the world, a range of conferences and forums for Chief Nuclear Officers or Plant Managers to industry working groups and workshops.

These events bringstogether leaders and professionals of all levels from around the globe, to share insights and operating experience, discuss emerging trends, and establish valuable connections. Recognising the importance of continuous learning and career development, WANO goes a step further by offering secondment opportunities, enabling members to gain practical experience in different settings. Ultimately, WANO aims to provide a holistic approach in the improvement of safety and reliability standards in the nuclear industry, which is facilitated with the creation and continuous support of this community that comes together with the mutual understanding that sharing knowledge and experience is extremely beneficial for all parties concerned.

The association brings together important stakeholders to develop new solutions to industry challenges, with the ultimate goal of optimising plant performance. Although great progress has been made to maximise safety and reliability since the establishment of WANO, the industry’s operators have recently been working more closely together to take action to enhance performance yet further.

In 2019, a mandate for change was approved to shape the industry’s future with a view to supporting performance improvements more rapidly. The resulting initiative, called Action for Excellence: Shaping the Nuclear Future, helps plants compare themselves against standards of excellence and focus efforts to achieve and sustain excellent performance.

Reviews and Monitoring

Over a four-year cycle, Peer Reviews are used to focus on delivering an evaluation and assessment and Enhanced Performance Monitoring (ePM) tracks each plant’s progress and provides support as required. Through peer reviews, members learn and share worldwide insights on safe and reliable plant operation and thereby improve their own performance. The same principles extend to companies, in the form of the corporate peer review.

The ePM solution was introduced due to the need for a more agile and proactive approach. It provides a more continual view of current performance and trajectory, detecting early signs of declines and addressing them rapidly. This is monitored through indicators, observations, interviews, reviews of plant activities and analysis of other data and helps high-performing plants maintain their performance and guides other plants to improve more quickly and sustainably.

The two methods, Peer Review and ePM, work together to provide a clear view of performance, identifying areas with the greatest potential for improvement and the level of support and attention required to improve and meet the highest standards of safety and reliability.

Trends and performance monitoring is used to collect, screen and analyse operating experience and performance data, providing lessons learnt and industry performance insight reports. To achieve this, however, it is fundamental that the plants are willing to openly share their operating experience and performance data for the benefit of other nuclear operators throughout the world.

Finally, it is important for operators to unite to enhance leadership skills and professional knowledge through workshops, seminars, training courses and leadership courses. These activities help provide plant personnel with the leadership knowledge, skills and standards needed to support the highest levels of nuclear safety and excellence, enabling different regions to compare their operations and emulate best practices.

The Future of Nuclear Safety

Looking ahead, the large variety of new units and entrants that are on the horizon will need to prepare for safe and reliable operations. The global landscape is witnessing major changes, with novel opportunities and challenges rippling across operators and various stakeholders. While some new units find their place within existing, well-established fleets and regulatory frameworks, a growing number of nations are now envisioning a nuclear dimension in their national energy mix for the very first time.

In the midst of this transformative era, each country or area introduces a unique blend of culture, regulatory frameworks, and operator dynamics. Along with the incorporation of advanced safety features in new units, the journey of constructing, initiating, and maintaining these plants safely demands bespoke approaches tailored to the specific needs of each participant.

As new units begin to come onstream they will receive operational readiness reviews, and pre-startup reviews, and long before operation begins, new plant operators will participate vital training on nuclear safety culture, operator fundamentals, organisational effectiveness and oversight and operational decision-making – areas that match typical nuclear project milestones.

Industry operating experience has shown that new nuclear units benefit from focused support during their initial phases of operation, particularly during commissioning, startup, and early operation stages. These stages involve complex processes, such as testing systems, conducting initial fuel loading, and gradual ramping up power generation. During commissioning and startup, various systems and components undergo testing and integration to ensure they function as intended.

New entrants in the industry are supported throughout this process, with New Unit Assistance missions and Pre-Start-up Peer Reviews, invaluable to ensure a smooth, successful, cost-effective and time-efficient transition from construction to commercial operation. Since 2015, new operators have received 159 WANO New Unit Assistance missions to 53 new units worldwide, facilitating a smooth start and transition to full operation.

About 18 months before fuel load, operational readiness assistance reviews help to ensure smooth progress towards completion of plant construction and approach the scheduled start up on time. A few months before the first fuel load, a pre-start-up peer review and observation of operating crew performance in the simulator help verify the readiness of equipment and crew.

Hands-on, face to face interactions are essential for new operators to prepare them for the crucial transition from construction into commercial operation. Then, as part the global nuclear community new operators receive constant support to sustain safe and reliable performance throughout the entire operating lifecycle.