Proposed rule · 2025-13817

Alternative Method for Calculating Embrittlement for Steel Reactor Vessels

The U.S. Nuclear Regulatory Commission (NRC) is denying a petition for rulemaking, dated August 19, 2019, submitted by Thomas A. Bergman on behalf of NuScale Power, LLC. The petition was docketed by the NRC on September 11, 2019, and was assigned Docket No. PRM-50-120. The petitioner requested that the NRC revise its regulations to add an alternative formula for calculating the mean value of the transition temperature shift described in American Society for Testing and Materials Standard E900-15 to the NRC's regulations and guidance documents. The NRC is denying the petition because the petitioner did not demonstrate the immediacy of any safety issues in the concerns raised in the petition and did not provide any new information that would warrant revision of the NRC's regulations.