Document: NUREG-0800
Document ID: ef559b35-0671-46e4-b172-09155cca8b81
Document Type: srp
Title: SPECTRUM OF ROD DROP ACCIDENTS (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350427.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.4.9
CFR Part: 
CFR Title: 

Content:
for zero or low power initial conditions, and fuel cladding dryout for rated power initial conditions. III. REVIEW PROCEDURES 1. Review of the applicant's analyses showing compliance with the first of the above criteria is carried out as follows: a. The reviewer verifies that the applicant has considered a spectrum of initial conditions for this event that covers the range of time-in-cycle and initial power levels. b. The reviewer verifies that the maximum expected individual control rod worths are used. In developing control rod worth criteria, the nominal control rod withdrawal pattern must be considered, as well as those abnormal patterns that are not precluded by an instrumentation system accepted under the review of SRP Section 7. c. The reviewer determines that an acceptable and conservative -function is used to describe the control rod worth as a function of control rod position and that the control rod position as a function of time is suitably conservative. d. The reviewer determines that conservative reactivity coefficients, notably the Doppler coefficient, are used and that they are compatible with those described in SRP Section 4.3. e. The reviewer assures that the scram action is conservatively represented in the use of the integral scram worth curve (SRP Section 4.3) and in the use of the scram delay time. f. The reviewer checks the analytical methods or assures that they have been reviewed and approved previously. The reviewer may also perform an independent audit calculation using methods acceptable to the staff. The applicant's methods should account conservatively for all major reactivity feedback mechanisms. 2. The reviewer inspects the results of the calculation of maximum reactor pressure to determine compliance with the second criterion listed in subsection II of this SRP (the reviewer may do an audit calculation when appropriate). 15.4.9-2 Rev. 2 - July 1981 3. The number of fuel rods experiencing clad failure and fuel melting is determined