France is the country of civilian nuclear power. As early as 1952, the first five-year plan for the development of nuclear energy was approved. The construction of nuclear power plants accelerated from 1974, the year of the first oil shock.

Today, Atomic energy is the main source of electricity production, with 56 active reactors. And, with the announced construction of six EPR2 and the emergence of SMR modular reactors, nuclear power is asserting itself as a key component of the national strategy towards carbon neutrality.

Despite this long history, nuclear power is a cause for concern. Very early on, France established a rigorous organization to ensure nuclear safety and security.

Often confused, these two terms refer to different, but complementary, missions with a common purpose: the protection of people, human health and the environment. Decryption.

What is nuclear safety?

The concept of nuclear safety is defined in France by article 591-1 of the Environmental Code and internationally by the IAEA (International Atomic Energy Agency).

Nuclear safety: definition

In French law, nuclear safety represents “all technical provisions and organizational measures relating to the design, construction, operation, operation, decommissioning and dismantling of basic nuclear installations as well as to the transport of radioactive substances, taken in order to prevent accidents or to limit their effects”.

In concrete terms, according to the IAEA, nuclear safety focuses on controlling unintended risks, such as technical incidents in power plants or natural disasters.

It aims to secure the design and operating conditions of nuclear installations in order to prevent the risks of technical failures and accidents and mitigate their consequences.

The main nuclear safety measures

Nuclear safety measures are the subject of extensive information to the general public, in accordance with the 2006 TSN Nuclear Transparency and Security Act.

Nuclear safety focuses its actions on:

• The design and construction of nuclear installations, based on the principle of defense in depth. Measures are taken at all levels to ensure the safety of nuclear installations: redundancy and diversification of safety systems, design of successive lines of defense to control the chain reaction, creation of three airtight safety barriers to contain radioactive materials (confinement enclosure, primary circuit shell and fuel rod jacket), physical separation of equipment. The installations are designed according to the principle of single failure to continue to perform certain functions even in the event of a technical failure of a system or equipment. Nuclear power plants are also equipped with safety systems that are triggered in the event of an accident (emergency power supply for the generators, core cooling system, enclosure spray circuit).
• Operation and maintenance procedures, with daily monitoring of installations and continuous improvement of systems based on feedback.
• The training personnel, with six weeks of training per year for jet pilots, simulation exercises and emergency plans.
• Control and surveillance systems.

What is nuclear security?

The Environmental Code seems to consider nuclear safety as a more generic concept than nuclear safety. But in reality, it refers to well-defined missions that are complementary to security.

Nuclear safety: definition

The Environmental Code defines nuclear safety as a concept that “includes nuclear safety, radiation protection, the prevention and fight against malicious acts as well as civil security actions in the event of an accident.”

In practice, again according to the IAEA, the Nuclear security focuses on risks of voluntary origin., caused by malicious acts (thefts, sabotages, terrorist threats, diversion of radioactive materials, unauthorized access...).

The main nuclear security measures

Nuclear security measures are more confidential than nuclear safety measures. The risk is indeed to disclose too much information to malicious persons.

More specifically, nuclear security focuses on:

• Physical protection of nuclear power plants and radioactive materials, both in nuclear installations and during transport (robust design of transport packages, safety devices, prevention of material losses, etc.).
• Control and follow-up physical and accounting of nuclear materials, nationally and internationally.
• Access and authorization management, with the geographical division of sectors.
• Cybersecurity of control systems.
• Surveillance, Intelligence, and Deterrence by making it difficult to physically access facilities and to access sensitive information.
• The training staff, with simulation exercises and emergency plans.

Nuclear safety and security actors

In terms of nuclear safety and security, the organizational principles are the same regardless of the country. They are based on the responsibility of operators, the designation of a competent authority, an authorization system and a control system.

The primary responsibility of the operator

The legislative and regulatory framework affirms the primary responsibility of nuclear operators for the safety and security of installations. In France, this responsibility falls to EDF , the sole operator of the nuclear fleet.

Thus, the operator must:

• Design, implement, and maintain the appropriate technical arrangements and organization to achieve levels of safety and security that meet regulatory requirements.
• Deploy a quality system in the areas of safety and security by ensuring a first level of control.
• Former its staff to guarantee a high level of skills.
• Inform the Nuclear Safety Authority (ASN) events involving the safety or security of installations.

In France, EDF also has a elite emergency unit : The Nuclear Rapid Action Force (FARN). Its mission: prevent a nuclear accident from becoming a disaster for humans and their environment.

Unique device in the world, the FARN can intervene in less than 24 hours in an emergency situation to restore a nuclear power plant to a safe state, ensure the protection of workers and limit the consequences of a nuclear accident.

Nuclear safety actors in France

The Nuclear Safety Authority (ASN)

The Nuclear Safety Authority (ASN) Is theNuclear control authority in France since 2006.

Independent administrative authority, ASN controls the safety level of nuclear installations and regulates the transport of radioactive materials. It establishes technical and organizational requirements and ensures compliance with standards and regulations.

THE ASN monitors nuclear power plants throughout their lives, from their design to their dismantling, including their construction, operation and decommissioning.

The authority regularly reassesses nuclear risks and may require the operator to upgrade the regulatory and technical facilities.

The Institute for Radiation Protection and Nuclear Safety (IRSN)

The Nuclear Safety Authority is supported by Institute for Radiation Protection and Nuclear Safety (IRSN).

Center of technical and scientific expertise, IRSN analyzes the safety of nuclear installations, infrastructures for transporting radioactive materials or centers for the reprocessing, storage and management of radioactive waste. The Institute ensures that safety and radiation protection devices guarantee the protection of workers, the population and the environment.

IRSN carries out research and development activities on nuclear and radiological risks, to strengthen nuclear safety. His work focuses, for example, on core fusion, fire in a confined environment or the impacts of material aging.

Nuclear safety actors in France

Attached to the Ministry of Ecological Transition, the Senior defense and security official (HFDS) is the guarantor of nuclear security in France, in collaboration with other nuclear players (ASN, IRSN, EDF...)

Authorization to create or dismantle nuclear installations, intelligence, crisis management, confidentiality and protection of sensitive information, identification of malicious threats: the State remains the main actor in nuclear security.

Its analyses help to design and size security systems, deployed by operators and controlled by ASN.

The prescriber of international safety and security standards: the IAEA

Nuclear safety and security are the responsibility of operators and states. But the International Atomic Energy Agency (IAEA) establishes international regulations. Its safety standards and codes of conduct serve as the basis for national laws and regulations.

Through trainings, the IAEA helps its member states apply standards and build expertise on nuclear risks. The international agency reserves the right to inspect and control national security, safety and radiation protection systems.

ASNR bill (Nuclear Safety and Radiation Protection Authority)

In a context of the revival of civilian nuclear power, parliamentarians adopted on April 9, 2024 The ASNR bill. The objective: to optimize the effectiveness of safety and security in order to strengthen the control of nuclear risks. The law provides for Created at 1^Er January 2025 from the Nuclear Safety and Radiation Protection Authority (ASNR), born of merger of ASN and IRSN.

As an independent administrative authority, the ASNR will take over the expertise, research and training missions from ASN and IRSN. She will be responsible for the control of nuclear installations, the investigation of safety cases and radiation protection.

Despite its adoption, this controversial law continues to be debated. Its opponents denounce the loss of independence and transparency of experts and the lack of distinction between expertise and decision. Next step: the opinion of the Constitutional Council before promulgation.