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Generic Reactor Safety (GRS)



The objective of the Technical Safety Review of Generic Reactor Safety (TSR-GSR) is to provide Member States with an early evaluation of a vendor's new nuclear power plant design's safety documentation (eg. preliminary safety analysis report, PSAR) against the IAEA Safety Standards..

Scope of the review

The scope of the review is defined by the Requesting Party in consultation with the IAEA and should typically take into consideration aspects such as:

-        The stage of development of the design which can range from conceptual to rather mature design ready for licensing,

-        The available documentation, which can range from general design description to a generic or specific PSAR,

-        The level of information available on aspects such as: site, safety analysis, operation, waste management, decommissioning, and

The safety documentation needed for the GRS review is a PSAR. However, dependent on the stage of the design and of its documentation a dedicated report might be provided which as a minimum should contain:

-        The design description including details on the design of systems performing the safety functions;

-        The safety approach for the design

-        The safety objectives and criteria the design has to meet.

-        Information on the R&D and safety assessment performed or planed for validating the design

-        The intended content of the safety analysis report 

Also, the documentation can include, if available:

-        The initiating events and hazards lists

-        The DSA and when available PSA analysis

-        Details on design of systems

-        Safety classification

The subject of the GRS review is the assessment of the comprehensiveness and completeness of the safety documentation developed by vendors against the IAEA Safety Standards at the fundamentals and requirements levels. Only requirements specific to the design and commensurate with available documentation and maturity of the design, usually without consideration of siting or plant management during operation are addressed.  
The framework of TSR-GRS review is based on the following set of applicable IAEA Safety Standards:

-         Fundamental Safety Principles (IAEA Safety Standards Series No. SF-1)

-        Safety Requirements on Safety Assessment for Facilities and Activities (IAEA Safety Standards Series No. GSR Part 4 (Rev. 1)

-        Safety of Nuclear Power Plants: Design (IAEA Safety Standards Series No. SSR-2/1 (Rev. 1).

The review focuses primarily on identification of whether issues in the selected standards are being considered in the design and documentation. The review does not evaluate the implementation of the requirements, i.e. the correctness of technical claims made in the PSAR by vendors is not addressed. Furthermore, the review does not address specific details of compliance of the evaluated safety documentation to the level of detail provided in IAEA safety guides.

The standards at the level of guides are used only for clarification or interpretation of a given requirement when necessary.


The TSR-GRS offers interested Member States a number of benefits including:

-        As the review is conducted by a team of internationally respected and independent experts with no conflict of interest with the RP, the review ensures respect for the findings and increases confidence of potential customers in the design meeting regulatory requirements with low risk.

-        The review increases confidence of the public in the safety of the design.

-        Provides the opportunity to assess the scope of the safety documentation and analysis made by vendors and highlights issues important to safety by identifying potential gaps or weaknesses in documentation.

-        Provides a focus and foundation for the subsequent more detailed individual evaluation or licensing process which remains a sovereign activity of the Member State.

-        As it can be undertaken for designs in different stages of evolution including a concept design, potential issues with the design are identified early before significant expenditure. It can be conducted in stages addressing the evolution and maturing of the design and its documentation.

-        Focus on safety aspects of the design ensures, and demonstrates that, attention is being paid to them from the earliest stages helping to prevent a design group becoming trapped in a false way of thinking about the design.

-        Recommendations carry weight that means they will be addressed by the RP thus improving the design or the safety case.

-        Can help to clarify the latest interpretation of requirements and current practices in meeting them.  (important for IAEA)

-        Follow on missions can be requested to explore identified issues in more depth. This could be using another review type, e.g. DS review.

-        Provides the first level of safety documentation (safety case) screening against internationally accepted Safety Standards, thereby contributing to international harmonization.

GRS Reviews Conducted



Member State



GRS documentation of CAP 1400




GRS documentation of ACP100




GRS documentation of ACP1000




GRS documentation of VVER TOI




GRS documentation of ACPR 1000+




GRS documentation of AES2006




GRS documentation of APR1000




GRS documentation of APR1400




GRS documentation of AP1000




GRS documentation of ATMEA1




GRS documentation of ACR1000, AP1000, ESBWR, EPR

United Kingdom