Document: NUREG-0800
Document ID: ff5838f8-986a-4d8b-a039-fb26df280426
Document Type: srp
Title: – 15.5.2
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070725.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.5.1
CFR Part: 
CFR Title: 

Content:
eeded during an anticipated operational occurrence.26 DC. General Design Criterion 26 (GDC 26), as it relates to the reliable control of reactivity 27 changes to assureensure that specified acceptable fuel design limits are not exceeded, 28 including anticipated operational occurrences. This is accomplished by assuringensuring that appropriate margin for malfunctions, such as stuck rods, areis 29 30 accounted for. The basic objectives in reviewing the events leading to an increase in reactor coolant inventory are: 1. To identify which of the moderate frequency events leading to a coolant inventory increase are the most limiting. 2. To verify that, for the most limiting transients, the plant responds to the core flow increase in such a way that the criteria regarding fuel damage and system pressure are met. The specific criteria necessary to meet the requirements of GDC General Design Criteria 10, 31 15, and 26 for incidents of moderate frequency are: a. Pressure in the reactor coolant and main steam systems should be maintained below 110% of the design valvesvalues (Ref. 2)in accordance with the ASME Boiler and Pressure Vessel Code.32 b. Fuel cladding integrity shall be maintained by ensuring that the minimum departure from nucleate boiling ratio (DNBR)DNBR remains above the 95/95 DNBR limit for PWRs 33 and the CPR critical power ratio (CPR) remains above the MCPRminimum critical 34 power ratio (MCPR) safety limit for BWRs based on acceptable correlations (see SRP 35 Section 4.4). c. An incident of moderate frequency should not generate a more serious plant condition without other faults occurring independently. d. An incident of moderate frequency in combination with any single active component failure, or single operator error, shall be considered and is an event for which an estimate of the number of potential fuel failures shall be provided for radiological dose calculations. For such accidents, fuel failure must be assumed for all rods for which the 36 DNBR or