Document: NUREG-0800
Document ID: 598d070d-fb96-43ce-ad4f-27f14623be46
Document Type: srp
Title: NUREG-0800
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350119.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15
CFR Part: 
CFR Title: 

Content:
y are turbine trip, loss of external load, steam pressure regulator malfunc- tions, main steam isolation valve closure (in BWRs), loss of condenser vacuum, loss of nonemergency ac power to the station auxiliaries, and loss of normal feedwater flow.* All these postulated transients have been reviewed. It was found that the most limiting in regard to core thermal margins and pressure within the reactor coolant and main steam systems was the transient. This transient was xThe SER should present one statement for moderate frequency transients involv- ing an unplanned decrease in heat removal by the secondary system. thus, t!he results of the reviews under SRP Sections 15.2.6 and 15.2.7 are included in this statement. 15.2.1-6 Rev. 1 - July 1981 evaluated by the applicant using a mathematical model that had been previously reviewed and found acceptable by the staff. The parameters used as input to this model were reviewed and found to be suitably conservative and in accordance with the recommendation of Regulatory Guide 1.105. The results of the analysis of the tran- sient showed that cladding integrity was maintained by ensuring that the maximum departure from nucleate boiling ratio (or minimum critical heat ratio for a BWR) did not decrease below _ and that the maximum pressure within the reactor coolant and main steam systems did not exceed 110% of their design pressures. V. IMPLEMENTATION The following is intended to provide guidance to applicants and licensees regard- ing the NRC staff's plans for using this SRP section. Except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the Commission's regulations, the method described herein will be used by the staff in its evaluation of conformance with Commission regulations. Implementation schedules for conformance to parts of the method discussed herein are contained in the referenced regulatory guides. VI. REFERENCES 1. Regulatory Guide 1.70,