Document: NUREG-0800
Document ID: d4441736-a9bb-45c2-8d16-d23e8312ab08
Document Type: srp
Title: CHEMICAL AND VOLUME CONTROL SYSTEM MALFUNCTION THAT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070717.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.4.6
CFR Part: 
CFR Title: 

Content:
ntrol of reactivity 23 changes to assure that specified acceptable fuel design limits are not exceeded, including anticipated operational occurrences. This is accomplished by assuring that appropriate margin for malfunctions, such as stuck rods, are accounted forcontrol rods being capable of reliably controlling reactivity changes to assure that under conditions of normal operation, including anticipated operational occurrences, and with appropriate margin for malfunctions such as stuck rods, specified acceptable fuel design limits are not exceeded . 24 The general objective of the review of moderator dilution events is to confirm that either of the following conditions are met: 1.- The consequences of these events are less severe than the consequences of another 25 transient that results in an uncontrolled increase in reactivity and has the same anticipated frequency classification., or26 2.- The plant responds to the events in such a way that the criteria regarding fuel damage and 27 system pressure are met and the dilution transient is terminated before the shutdown margin is eliminated. Specific criteria necessary to meet the relevant requirements of GDC 10, 15, and 26 are as follows: 1. Pressure in the reactor coolant and main steam systems should be maintained below 110% of the design valvues . (Ref.erence 14) 28 29 DRAFT Rev. 2 - April 1996 15.4.6-4 2. Fuel cladding integrity shall be maintained by ensuring that the minimum departure from nucleate boiling ratio (DNBR) remains above the 95/95 DNBR limit for PWRs and the 30 CPR remains above the MCPR safety limit for BWRs based on acceptable correlations 31 (see SRP Section 4.4). 3. An incident of moderate frequency should not generate a more serious plant condition without other faults occurring independently. 4. 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