Document: NUREG-0800
Document ID: 16922d4c-3f36-4add-8a31-0ec35a44f030
Document Type: srp
Title: REACTOR COOLANT SYSTEM HIGH POINT VENTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070770005.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.12
CFR Part: 
CFR Title: 

Content:
ble method of complying with the relevant NRC requirements identified in Subsection II. For DC and COL applications submitted under Part 52, the level of information reviewed should be consistent with that of a FSAR submitted in an OL application. However, verification that the as-built facility conforms to the approved design is performed through the ITAAC process. 1. The organization responsible for the review of reactor thermal-hydraulic systems reviews the vent system description to determine that the vent paths are capable of venting RCS high points. For areas that may be impractical to vent, such as the U-tubes in steam generators, the reviewer determines that adequate procedures have been developed to assure coolability. 2. At request of the reviewer of reactor thermal-hydraulic systems, the organization responsible for the review of instrumentation and control systems reviews the instrumentation, vent controls, and power source to establish that a single failure will not prevent isolation of the vent system. 5.4.12-8 Revision 1 - March 2007 3. The reviewer of reactor thermal-hydraulic systems examines valve redundancy and other methods to minimize inadvertent actuation. The review should compare the methods to prevent inadvertent actuation with those of other safety-related systems. 4. The reviewer of reactor integrity issues related to the RCPB evaluates the vent system to determine that all requirements for the RCPB are met. 5. The reviewer of reactor thermal-hydraulic systems examines the size of the vent line and orifices to see if the smallest flow area is smaller than the LOCA definition. If the vent path capacity is of LOCA size, a LOCA analysis should be provided. In a case where the pressurizer power-operated relief valve or its equivalent is used for pressurizer venting, an inadvertent valve opening or failure would initiate a LOCA. However, the path also contains a block valve, and this LOCA should have been addressed as part of the 10 CRF 50.46