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:
eedwater pumps). This results in an increase in reactor pressure, but the increase is well within the ASME Code limit. Therefore, for the four overcooling transients of SRP Section 15.1.1, the reactor coolant pressure needs to be analyzed to ensure that the pressure acceptance criterion is satisfied. Meeting the requirements of GDC 15 provides assurance that the design conditions of the reactor coolant pressure boundary are not exceeded for the four anticipated operational occurrences evaluated in this SRP section involving excessive heat removal by the secondary system.37 (c) Compliance with GDC 20 requires that the reactor protection system be designed to initiate the operation of appropriate systems automatically, including the reactivity control systems, to ensure that specified acceptable fuel design limits are not exceeded during normal operation, including anticipated operational occurrences. GDC 20 is applicable to this section because the reviewer evaluates the reactor protection system that operates to shut down the reactor automatically to terminate the events (anticipated operational occurrences) analyzed in this SRP section. The events are terminated by the reactor protection system in a timely manner such that fuel cladding integrity is maintained. For a BWR, this means that the minimum value of the critical power ratio reached during the transient should be such that 99.9% of the fuel rods in the 15.1.1-7 DRAFT Rev. 2 - April 1996 core would not be expected to experience boiling transition during core-wide transients. This limiting value of the minimum critical power ratio (MCPR) is called a safety limit. For the ABWR its value is 1.07. For a PWR, this means that the minimum value of the departure from nucleate boiling ratio (DNBR) reached during the transient must remain above the 95/95 DNBR limit for the applicable DNBR correlation. For the CE80+ design, this value is 1.24. Meeting the requirements of GDC 20 provides assurance that specified