In 2017 we celebrated our company’s 50th birthday. The Assystem adventure started in the nuclear sector when the French State began to build the country’s fleet of nuclear power plants (NPPs) as well as the factories needed to produce the fuel for the plants and process their nuclear waste. Over the fifty years that have gone by since then, Assystem has grown from nothing into the large group that it is today, occupying a leading position in commissioning complex facilities. NPPs are complex, not just because of what they actually are, but also because they are subject to extremely stringent rules and regulations regarding safety.
One of the main roles of a nuclear safety inspectorate is to keep the public informed, as transparency is vital in the nuclear sector. The public will not accept nuclear energy if there is no transparency.
Nuclear safety encompasses a wide range of rules and regulations covering technical, people-related and organisational issues, which are designed to enable NPPs to operate while limiting of the possibility of incidents or accidents. This means constantly devising ways of mitigating the effects of any potential accidents or incidents, right from the design phase and throughout the plant’s life cycle. The overall objective is to safeguard the NPP and, more importantly, its surrounding environment, starting with the people who work there. Countries that use nuclear power each have a nuclear safety inspectorate which oversees nuclear activities and investigates applications for licenses to build, modify or decommission NPPs. One of the main roles of a nuclear safety inspectorate is to keep the public informed, as transparency is vital in the nuclear sector. The public will not accept nuclear energy if there is no transparency. This inspectorate also determines the methods and processes that nuclear operators have to follow. In France, the authority responsible for these tasks is the Autorité de Sûreté Nucléaire (Nuclear Safety Agency, or ASN). The ASN is known for its sanctioning powers but its key purpose is to oversee and strengthen best practices in the industry.
Assystem’s teams work at nuclear facilities on a daily basis, handling materials and designing and modifying systems and equipment.
Nuclear operators, including EDF, Framatome, Orano, the CEA, ITER and the CERN are required to report directly to the ASN. Although Assystem is not a nuclear operator, it is a participant in and partner of the French nuclear sector and as such holds major responsibilities. Assystem’s teams work at nuclear facilities on a daily basis, handling materials and designing and modifying systems and equipment. This means that nuclear security, in its broadest sense, forms part of all of the Group’s projects.
The nuclear industry is always looking for the best available techniques and using these techniques is even a legal requirement. The problem is that it is difficult to constantly innovate in the nuclear sector – nuclear players obviously need to be innovative but at the same time they need to utilise tried and tested techniques and technologies. If we put French nuclear plants’ total number of operating years end to end we get several thousand cumulative reactor years – that’s a colossal amount of experience. Nuclear is a sector in which the most important thing is to develop a safety culture by learning from experience. It isn’t an industry for trying out a digital gadget invented just three months ago – rigour and prudence have always been, and will remain, the industry’s watchwords. That is why we talk about a safety culture.
In view of all of this, it is important to be constantly on the lookout for the highest-performing and most efficient technologies but also to act prudently and keep a critical eye on what’s going on. It’s not because a process has always been used that it’s necessarily the best and conversely, if something is not happening exactly as it used to, then maybe that’s a pointer for change. From on-site operators right up to top executives, each and every person is a link in the safety culture chain. And spearheading a safety culture is the very raison d’être of my job – Nuclear Safety Director – which was created five years ago within Assystem.
For us as a department, we felt there was a real need to develop the safety sector – to develop safety as a profession, as well as processes and methods, but also more generally, to develop safety as a culture. We are involved in all aspects of a project’s performance, from its design and structural phases to on-site operation and team project work. We also work on projects for renovating and decommissioning nuclear facilities for our clients who are major players in the nuclear industry in France and throughout the world. And we contribute to maintenance operations right from their preparation phase.
The need for safety and security in the nuclear industry goes without saying and there have been several tragic accidents in the industry’s history, such as Chernobyl and Fukushima. While there have been no serious accidents in France there have been some incidents and deviations. Each and every deviation, however small, is closely monitored. And we’re not talking about accidents or incidents here but simply deviations, such as if we notice that a piece of equipment that would have a role to play in an accident is malfunctioning. This strict monitoring of events is reported to the ASN and all events are fully analysed. In order to ensure total transparency, the ASN makes its reports available to the general public.
Engineers work at the very core of the nuclear safety system, which is underpinned by numerous ultra-technological aspects.
Assystem felt that it was important to put in place a specific nuclear safety structure to provide support to all of the Group’s teams. This structure acts as a platform for developing and exchanging know-how, sharing learning experiences and generally helping to embed a safety culture. Over time, our clients’ safety and security requirements have become increasingly demanding and engineering has a key role to play in the nuclear safety culture. Engineers work at the very core of the nuclear safety system, which is underpinned by numerous ultra-technological aspects. Operators applying for licenses from the ASN have to provide mathematical proof that the risks related to their facilities are contained and below the original thresholds as a public inquiry has to be carried out before a nuclear power plant can be built.
At each stage of an NPP’s life-cycle, even if the risks are reduced to a minimum, we have to envisage what would happen if the risk mitigation measures put in place don’t work. This “what if” approach even has a specific name: “defence in depth”. Safety engineers need to envision the worst-case scenario and take preventive measures even for failures that they are almost sure won’t happen. This approach is a compulsory requirement of the nuclear safety inspectorate and supporting and demonstrating the safety of sites and NPPs are extremely important aspects of Assystem’s engineering work.
We have put in place specific nuclear safety methods and processes as well as risk analysis matrices. For instance, we can assess a plant’s fire-resistance capacity and its ability to effectively manage an incident.
Another major challenge in the coming years both for nuclear operators and major electricity companies will be to manage their installed fleet of NPPs and the life-spans of each one. In France, life-spans are not pre-determined but instead are reassessed by the ASN every ten years. During these assessments the ASN determines what updates and/or improvements are required before deciding whether or not to issue a license for the NPP to operate for a further ten years. The ASN performs continuous controls and can halt the operation of an NPP at any time. Clearly, Assystem has a role to play in this domain.
We have to stay one step ahead by imagining scenarios that we don’t always know are possible. This is part of the defence in depth approach to nuclear safety.
Since Fukushima, different risks and incidents (such as earthquakes, fires and floods) are no longer looked at separately but instead from a holistic perspective, taking into account all potential threats and incidents cumulatively. For instance, a flood can lead to a power outage, which can in turn result in a loss of confinement. It is essential to factor in multiple threats when assessing nuclear safety risks. Another example is earthquakes, whose damage can lead to dams breaking and therefore floods, or short-circuits that can cause fires. We can’t predict every disaster scenario but we can be aware of threats that exist, such as a dam that is about to break or extreme weather events. We also need to assess the risk of a global cybernetics failure as well as cyber-attacks. We have to stay one step ahead by imagining scenarios that we don’t always know are possible. This is part of the defence in depth approach to nuclear safety. If an intruder enters a site either physically or virtually, how do we deal with this threat? We can’t rule out this risk, and even if we think we can, then we can’t act as if we can!
Digital technology, and particularly virtual reality, can be used to prepare for work conducted in hazardous environments and to certify equipment without running any risks.
Digital technology is set to bring about significant changes in nuclear safety and the process has already started. Today, all NPPs are initially designed digitally in 3D, with additional parameters for factoring in such things as the mathematical analysis of radiation risks. Digital technology, and particularly virtual reality, can be used to prepare for work conducted in hazardous environments and to certify equipment without running any risks. Digital modelling is definitely the way forward. On the other hand, there are certain NPPs that have been operating for many years and in order to extract data from them we need to use artificial intelligence and a big data approach. By combining digital technology and statistics we can enhance the learning experience.
Digital technology also plays an important role in integrated logistics support. Nuclear operators need a management system that can factor in every aspect of their business including all of the procedures and interfaces related to managing inventories and old and new-generation components in order to ensure that everything is properly integrated into maintenance procedures. Configuration management is absolutely vital for complex facilities such as NPPs, where equipment and components are continually renewed and issues of compatibility and non-regression are crucial. And this is an area in which we are increasingly working with major nuclear operators.
Nuclear security covers a relatively wide range of concepts, all aimed at achieving what is known as “the protection of interests”.
Article L593-1 of the French Environmental Code states “Basic nuclear facilities are subject to the provisions of this Chapter and Chapter VI of this section due to the risks and drawbacks they may represent in terms of public security and health and safety as well as the protection of nature and the environment.”
Article L593-2 of the Code defines basic nuclear facilities as (i) nuclear reactors, (ii) facilities used for preparing, enriching, manufacturing, processing or storing nuclear fuel or for processing, storing or stocking radioactive waste, (iii) facilities containing radioactive or fissile materials, (iv) particle accelerators, and (v) deep geological repositories of radioactive waste.
Nuclear security covers nuclear safety, radiation protection, preventing and combatting malicious acts, and public security measures in the event of an accident.
Nuclear safety is defined as all of the technical provisions and organisational measures put in place in relation to (i) the design, construction and operation of basic nuclear facilities right up to their decommissioning and dismantling, and (ii) the transport of radioactive materials, with a view to preventing or mitigating the effects of accidents.
Radiation protection is defined as protecting against ionising radiation and corresponds to all of the rules, procedures and prevention and surveillance systems aimed at preventing or reducing the harmful effects on people of exposure to ionising radiation, either directly or indirectly, including through environmental damage.