Document: NUREG-0800
Document ID: 7e0d3b3e-62c3-4492-ba89-6cebb4e82234
Document Type: srp
Title: SECONDARY CONTAINMENT FUNCTIONAL DESIGN
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340701.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.2.3
CFR Part: 
CFR Title: 

Content:
s occurring within the annular region formed by the secondary containment. The analyses are done using the CONTEMPT-LT computer code (Ref. 4). It should be noted that, for the analysis of the pressure and temperature response in the secondary containment for loss-of-coolant accidents within the primary containment, the present version of the CONTEMPT-LT only has 6.2.3-5 Rev. 2 - July 1981 the capability of calculating the pressure in the secondary containment up to the time the depressurization systems are actuated. The code is being improved to permit the calculation of the pressure response for the entire course of an accident. The analysis will be based on the guidelines given in subsection II of this SRP section, and code input data obtained from the SAR. CSB determines that the secondary containment design pressure is not exceeded and that the depres- surization time is consistent with that assumed in the AEB analysis of the radio- logical consequences of the accident. In addition, CSB determines that the primary containment external design pressure is not exceeded. CSB determines that all direct leakage paths have been properly identified, and from a review of the proposed leakage testing program that provisions have been made in the design of the plant to measure the fraction of total primary containment leakage that bypasses the secondary containment. CSB advises AEB of any inadequacies in the applicant's direct leakage assumptions used in the radiological analysis. At the operating license stage of review, LGB reviews technical specifications which specify the surveillance requirements for leakage testing of the secondary containment bypass leakage paths. CSB reviews analyses of the capability of the secondary containment system to resist exfiltration under post-accident conditions. If the secondary contain- ment leakage rate is in excess of 100% of the volume per day, CSB advises AEB in order that they may perform a special exfiltration analysis. CSB