Document: NUREG-0800
Document ID: 7e9d3620-7a94-488e-b2d5-992282113080
Document Type: srp
Title: NUREG408OO
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350480.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
stems including the reactivity control systems, to assure that specified acceptable fuel design limits are not exceeded as a result of anticipated operational occurrences. GDC 25 requires these limits shall not be exceeded for any single malfunction of the reactivity control systems, such as accidental withdrawal (not ejection) of control rods. Within the context of GDC 20 the staff considers operator error to be an anticipated operational occurrence, in addition to the consideration of single malfunction requirements of GDC 25, for which conformance to these requirements is to be evaluated. The applicant should perform analyses of the reactivity control systems* and analyze the consequences of operator error to assess the impact of these events on fuel design limits. If the results of these analyses show that specified acceptable fuel design limits may be exceeded for these events, the protection system must be designed to detect and terminate these events prior to exceeding these limits. With regards to the evaluation of malfunctions within the reactivity control systems, consideration should be given to failures which cause actions as well as prevent actions such that all possible effects are examined. Further, consideration of failures which could lead to single or multiple rod position changes or out of sequence rod patterns should be analyzed, as well as, failures which could lead to reactivity changes by boron control systems. C. REFERENCES 1. Surry 3 and 4 Safety Evaluation Report, March 26, 1974. 2. 10 CFR Part 50, Appendix A, General Design Criteria. Reactivity control systems include interlocks within the system which limit the consequences of control system failures. 7A-11' Rev. 2 - July 1981 BRANCH TECHNICAL POSITION ICSB 16 CONTROL ELEMENT ASSEMBLY (CEA) INTERLOCKS IN COMBUSTION ENGINEERING REACTORS [BTP has been deleted] ) 7A^12 Rev. 2 - July 1981 BRANCH TECHNICAL POSITION ICSB 19 ACCEPTABILITY OF DESIGN-CRITERIA FOR HYDROGEN MIXING AND DRYWELL VACUUM