PRA Methods Knowledge Base

Knowledge of the methods used in in the U.S. nuclear industry is in many cases distributed amongst different entities with various degrees of information availability and communication. This wiki provides a centralized, publicly available industry catalog for PRA methods in use.

Product Information

PRA Methods Knowledge Base Wiki

Product ID: 3002027587

Purpose

• Collaboratively develop a knowledge management tool for PRA methods used in the current PRA practices
• Support PRA practitioners in key activities, including improvement of risk metrics and assessing Newly Developed Methods
• Support PRA method developers with knowledge management of methods currently under development and/or evaluation

Objectives

• Allow industry PRA practitioners to provide continuous feedback on methods in use
• Provide easy access to information on available PRA methods to assist practitioners in their activities
• Retain consistency with existing processes and practices (e.g. RG 1.200)

Scope

This methods and tools on this wiki are intended to provide benchmark operating experience in analyses supporting the ASME/ANS Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications (RA-S, 2008 and RA-S-1.1, 2022).

How it Works

This wiki is a living document that is populated through input from individual contribution from NEI members and EPRI members. Those contributors provide input through the NEI form, available here: INPUT FORM

Definitions

From PWROG-19027-NP Revision 2, "Newly Developed Method Requirements and Peer Review", available at [1]
PRA Upgrade: A change in the PRA that results in the applicability of one or more Supporting Requirements (SRs) that were not previously included within the PRA (e.g., performing qualitative screening in Part 4 when this HRL was previously not applicable or the addition of a new hazard model), an implementation of a PRA method in a different context, or the incorporation of a PRA method not previously used.
PRA Method: An analytical approach used to satisfy a supporting requirement or collection thereof in the PRA. An analytical approach is generally a compilation of the analyses, tools, assumptions, and data used to develop a model.
Model: A qualitative and/or quantitative representation that is constructed to portray the inherent characteristics and properties of what is being represented (e.g., a system, component or human performance, theory or phenomenon). A model may be in the form, for example, of a structure, schematic or equation. Method(s) are used to construct the model under consideration.
PRA: A quantitative assessment of the risk, including technical elements for modeled hazards, associated with plant operation and maintenance that is measured in terms of frequency of occurrence of risk metrics, such as core damage or a radioactive material release and its effects on the health of the public [also referred to as a probabilistic safety assessment (PSA)]
PRA Maintenance: A change in the PRA that does not meet the definition of PRA upgrade.
State-of–Practice: Those practices that are widely implemented throughout the commercial nuclear power industry, have been shown to be technically acceptable in documented analyses or engineering assessments, and have been shown to be acceptable in the context of the intended application.
Consensus Method/Model: A method/model that the USNRC has used or accepted for the specific risk-informed application for which it is proposed.
Newly Developed Method: A PRA method that has either been developed separately from a state-of-practice method or is one that involves a fundamental change to a state-of-practice method. A newly developed method is not a state-of practice or a consensus method.

Disclaimer

Disclaimer: The information on this page is for knowledge management only. Inclusion within this site does not indicate any regulatory status, similarly, exclusion does not indicate a given method, tool, or data set is not suitable for use in operating nuclear power plants. Licensees should ensure their PRAs represent the as-built, as-operated plant, and remain in alignment with any license conditions or commitments. Participation is optional and voluntary. EPRI does not verify the information provided and the projects shown do not imply EPRI endorsement, verification, or review.

Contacts for Additional Information

• EPRI – For questions on EPRI research results or other EPRI questions, contact Fernando Ferrante.
• NEI – For questions on NDM process or coordination, contact Victoria Anderson.