Document: NUREG-0800
Document ID: 7b7303eb-a3a7-433b-8301-fcaba03194ea
Document Type: srp
Title: - 15.1.4
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070676.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.1.1
CFR Part: 
CFR Title: 

Content:
pressure regulator or pressure relief valve malfunctions, methods of thermal and hydraulic analysis, postulated sequence of events including time delays prior to and after protective system actuation, assumed reactions of reactor system components, functional and operational characteristics of the reactor protection system in terms of how it affects the sequence of events, and all operator actions required to secure and maintain the reactor in a safe condition. The results of the transient analysis are reviewed to ensure that the values of pertinent system parameters are within the ranges expected for the type and class of reactor under review. The parameters include: core flow and flow distribution, channel heat flux (average and hot), minimum critical power ratio (MCPR), departure from nucleate boiling ratio (DNBR), vessel water level, thermal power, vessel pressure, steam line pressure (for BWRs), steam line flow (for BWRs), feedwater flow (for BWRs), and reactivity. The sequence of events described in the SAR for these transients is reviewed by RSBSRXB. 5 The RSBSRXB reviewer concentrates on the need for the reactor protection system, the 6 engineered safety systems, and operator action to secure and maintain the reactor in a safe condition. The analytical methods are reviewed by RSB to ascertain whether mathematical modeling and computer codes have been previously reviewed and accepted by the staff. If a referenced analytical method has not been previously reviewed, the RSBSRXB reviewer 7 initiates a generic evaluation of the new analytical model. In addition, the values of all the parameters used in the new analytical model, including the initial conditions of the core and system, are reviewed. Review Interfaces8 The RSBSRXB will coordinate other branch evaluations that interface with the overall review 9 of the transient analyses as follows: A. The Instrumentation and Controls Systems Branch (ICSBHICB ) reviews the 10 11 instrumentation and controls aspects