Document: NUREG-0800
Document ID: a650b8f2-b0fa-4f0f-bc8f-55bb3f6ec603
Document Type: srp
Title: INADVERTENT OPENING OF A PWR PRESSURIZER PRESSURE RELIEF VALVE
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0708/ML070820094.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.6.1
CFR Part: 
CFR Title: 

Content:
pendix A, should be assumed in the analysis and should satisfy the positions of RG 1.53. The applicant's analysis of this transient should use an acceptable analytical model. If the applicant proposes to use analytical methods not previously reviewed and approved by the staff, the staff evaluates them for acceptability. For new generic methods, the reviewer initiates an evaluation of the new analytical model. The values of the parameters in the analytical model should be suitably conservative. The following values are acceptable. 15.6.1-5 Revision 2 - March 2007 A. The initial power level is taken as the licensed core thermal power for the number of loops initially assumed to operate plus an allowance of 2 percent to account for power measurement uncertainties unless the applicant can justify a lower power level. The number of loops operating at the initiation of the event should correspond to the operating condition that maximizes the consequences of the event. B. Conservative scram characteristics are assumed (i.e., for a PWR maximum time delay with the most reactive rod held out of the core and for a BWR a design conservatism factor of 0.8 times the calculated negative reactivity insertion rate). C. The core burn-up is selected to yield the most limiting combination of moderator temperature coefficient, void coefficient, Doppler coefficient, axial power profile, and radial power distribution. D. Mitigating systems should be assumed to be actuated in the analyses at setpoints with allowance for instrument inaccuracy in accordance with RG 1.105. Technical Rationale The technical rationale for application of these acceptance criteria to the areas of review addressed by this SRP section is discussed in the following paragraphs: 1. GDC 10 requires design of the reactor core and its coolant, control, and protection systems with appropriate margin so specified acceptable fuel design limits are not exceeded during any conditions of normal operation, including the effects