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TIRICE and TIMaSC

On this page:

Purpose

The Technology Inclusive, Risk-Informed Change Evaluation (TIRICE) process provides an alternative change evaluation process for determining if NRC approval is required before implementing certain facility changes to reactors that were licensed using the methodologies in NEI 18-04, Revision 1, "Risk-Informed Performance-Based Technology-Inclusive Guidance for Non-Light Water Reactor Licensing Basis Development," as endorsed by Regulatory Guide 1.233, "Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light Water Reactors."  The industry’s proposed guidance document for implementing the TIRICE process is NEI 22-05, “Technology Inclusive Risk Informed Change Evaluation (TIRICE): Guidance for the Evaluation of Changes to Facilities Utilizing NEI 18-04 and NEI 21-07.”

The Technology Inclusive Management of Safety Case (TIMaSC) process provides a process for the management of a licensing modernization project-based safety case. Examples of TIMaSC guidance includes how to manage the safety case in the event operating experience indicates reliability or capability targets for safety significant structures, systems, and components (SSCs) are not met or operating experience indicates reliability or capability targets for safety significant SSCs have more than anticipated margin.

Public Meetings/Documents

Date Design
01/31/2024 Submittal of NEI 22-05, “Technology Inclusive Risk Informed Change Evaluation (TIRICE) Guidance for the Evaluation of Changes to Facilities Utilizing NEI 18-04 and NEI 21-07”, Revision 0
05/11/2023 Technology Inclusive Management of Safety Case Process
05/09/2023 Technology Inclusive Risk-Informed Change Evaluation Process
09/13/2022 Technology Inclusive Risk-Informed Change Evaluation Process
06/09/2022 Technology Inclusive Risk-Informed Change Evaluation Process

Page Last Reviewed/Updated Tuesday, February 11, 2025