Document: NUREG-0800
Document ID: baab1f26-b869-4986-9c53-36842ceaa7c3
Document Type: srp
Title: SPECTRUM OF ROD DROP ACCIDENTS (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070723.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.4.9
CFR Part: 
CFR Title: 

Content:
mits on the potential amount and rate of reactivity increase. Such a design ensures that the effects of postulated reactivity accidents can neither (1) result in damage to the reactor coolant 15.4.9-3 DRAFT Rev. 3 - April 1996 pressure boundary greater than limited local yielding nor (2) sufficiently disturb the core, its support structures, or other reactor pressure vessel internals to cause serious impairment of core cooling capability. GDC 28 is applicable to SRP Section 15.4.9 because this section involves the review of reactivity excursions in BWRs resulting from control rod drop accidents. The review provides an assessment of the transient fuel enthalpy to determine whether cladding failure or fuel rupture is predicted to occur and, if so, to what extent. This review establishes both the coolability of the core after the transient and the source term used to evaluate the radiological consequences of the accident. It also determines the maximum reactor coolant pressure to ensure that stress limits for the reactor pressure vessel are not exceeded. Meeting the requirements of GDC 28 provides a level of assurance that fuel damage and reactor vessel pressure will not be excessive in the event of a control rod drop accident in a BWR.17 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 Chapter 7. 18 c. The reviewer determines that an acceptable and conservative function is used to