Document: NRC Regulatory Guide
Document ID: 61b22006-634a-415a-a204-22e515d96707
Document Type: regulatory_guide
Title: Pressurized-Water Reactor Control Rod Ejection and Boiling-Water Reactor Control Rod Drop Accidents + HISTORY - HISTORY 11/2016 – DG-1327 , Proposed Revision 0
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1612/ML16124A200.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.236
CFR Part: 
CFR Title: 

Content:
coolant, producing a pressure pulse that may challenge the integrity of the reactor pressure boundary. Harmonization with International Standards The NRC staff reviewed guidance from the International Atomic Energy Agency (IAEA), the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC) and did not identify any standards that provided useful guidance to NRC staff, applicants, or licensees. DG 1327, Page 7 C. STAFF REGULATORY GUIDANCE This guide describes analytical methods and limits that the staff of the NRC considers acceptable for use when analyzing a postulated PWR CRE accident and a postulated BWR CRD accident. 1. Limits on Applicability The analytical limits and guidance described may not be directly applicable to anticipated operational occurrences (AOOs) and other postulated accidents involving positive reactivity insertion (e.g., PWR excess load, PWR inadvertent bank withdrawal, PWR steam line rupture, BWR turbine trip without bypass, BWR rod withdrawal error). Furthermore, depending on design features, reactor kinetics, and accident progression, this guide may not be directly applicable to advanced LWRs and modular LWRs. Application of this guide beyond PWR CRE and BWR CRD, as well as the range of applicability described below, will be considered on a case-by-case basis. The applicability of the fuel rod cladding failure thresholds, fission product release fractions, and allowable limits on damaged core coolability provided in this guidance are limited as follows: 1.1 LWR fuel rod designs comprised of slightly enriched UO2 ceramic pellets (up to 5.0 wt% 235U) within cylindrical zirconium-based cladding, including designs with or without barrier lined cladding, integral fuel burnable absorber (e.g., gadolinium), or a pellet central annulus. This guidance is not applicable to mixed oxide (MOX) fuel rod designs. 1.2 The high temperature cladding failure threshold described in Section 3.1 is applicable to