Document: NUREG-0800
Document ID: 7abc5861-4ac1-4f27-ab53-f9997c382301
Document Type: srp
Title: SPECTRUM OF ROD EJECTION ACCIDENTS (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550014.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.4.8
CFR Part: 
CFR Title: 

Content:
iew procedures are based on the identified SRP acceptance criteria. For deviations from these acceptance criteria, the staff should review the applicant’s evaluation of how the proposed alternatives provide an acceptable method of complying with the relevant NRC requirements identified in Subsection II. Initial conditions and assumptions for the limiting scenario with respect to each Section II criteria (e.g. fuel failure, pressure, coolability) may be different. Further, limiting conditions for each fuel failure mechanism (e.g. DNB or PCM1) may be different. The review needs to consider these effects. 1. Review of the applicant's analyses showing that acceptance criterion II.1 is met proceeds as follows: A. A spectrum of initial conditions, which must include zero, intermediate, and full-power, is considered at the beginning and end of a reactor fuel cycle for examination of upper bounds on possible fuel damage. At-power conditions should include the uncertainties in the calorimetric measurement. B. From the initial conditions, considering all possible control rod patterns allowed by technical specification/core operating limit report power-dependent insertion limits, the limiting rod worths are determined. Where confirmation is necessary, the reviewer may calculate, as an audit, the worth of limiting rods. C. Reactivity coefficient values of the limiting initial conditions must be used at the beginning of the transient. The reviewer checks the reactivity coefficient curves used by the applicant with those reviewed under SRP Section 4.3. The Doppler and moderator coefficients are the two of most interest. If there is no three-dimensional space-time calculation, the reactivity feedback must be weighted conservatively to account for the variation in the missing dimension(s). 15.4.8-5 Revision 3 - March 2007 D. The reviewer inspects the control rod insertion assumptions, which include trip parameters, trip delay time, rod velocity curve, and differential rod worth.