Document: NUREG-0800
Document ID: 47be7233-5326-4a7d-a9c5-f3b91d565a72
Document Type: srp
Title: MINIMUM CONTAINMENT PRESSURE ANALYSIS FOR EMERGENCY CORE
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070492.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.2.1.5
CFR Part: 
CFR Title: 

Content:
date of issuance of this SRP section. 22 6.2.1.5-5 DRAFT Rev. 3 - April 1996 VI. REFERENCES The references for this SRP section are listed in SRP Section 6.2.1. 23 DRAFT Rev. 3 - April 1996 6.2.1.5-6 BRANCH TECHNICAL POSITION CSB 6-1 (Currently the responsibility of Containment Systems and Severe Accident Branch - SCSB)24 MINIMUM CONTAINMENT PRESSURE MODEL FOR PWR ECCS PERFORMANCE EVALUATION A. BACKGROUND Paragraph I.D.2. of Appendix K to 10 CFR Part 50(Ref. 1) requires that the 25 containment pressure used to evaluate the performance capability of a pressurized water reactor (PWR) emergency core cooling system (ECCS) does not exceed a pressure calculated conservatively for that purpose. It further requires that the calculation include the effects of operation of all installed pressure-reducing systems and processes. Therefore, the following branch technical position has been developed to provide guidance in the performance of a minimum containment pressure analysis. The approach described below applies only to the ECCS-related containment pressure evaluation pursuant to 10 CFR 50.46(a)(1)(ii) and not to the containment functional capability 26 evaluation for postulated design basis accidents. B. BRANCH TECHNICAL POSITION 1. Input Information for Model a. Initial Containment Internal Conditions The minimum containment gas temperature, minimum containment pressure, and maximum humidity that may be encountered under limiting normal operating conditions should be used. Ice condenser plants should use the maximum containment gas temperature. b. Initial Outside Containment Ambient Conditions A reasonably low ambient temperature external to the containment should be used. c. Containment Volume The maximum net free containment volume should be used. This maximum free volume should be determined from the gross containment volume minus the volumes of internal structures such as walls and floors, structural steel, major equipment, and piping. The individual volume