Document: NUREG-0800
Document ID: 15a004f9-6c99-4bc0-a858-efeaea553e8e
Document Type: srp
Title: REACTOR COOLANT SYSTEM HIGH POINT VENTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070440.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.12
CFR Part: 
CFR Title: 

Content:
designed, fabricated, erected, and tested and maintained to high quality standards. EB. General Design Criterion 14, as it relates to the reactor coolant pressure boundary being designed, fabricated, erected and tested to have an extremely low probability of abnormal leakage, of rapidly propagating failure, and of gross rupture. F. General Design Criteria 17 and 34 as they relate to the provision of normal and emergency power for the vent system components.31 G. General Design Criterion 19 as it relates to the vent system controls being operable from the control room.32 H. General Design Criterion 36 as it relates to the vent system being designed to permit periodic inspection.33 Specific criteria necessary to meet the regulations identified above and necessary to implement task action plan Item II.B.1 of NUREG-0718 and -0737 (References 16 and 17) are as follows: 34 1. The reactor coolant vent design must ensure that use of these vents during and following an accident does not aggravate the challenge to containment or the course of the accident.35 21. Vent paths shall be provided on high points of the reactor coolant system (including the 36 pressurizer on PWRs) to vent gases which may inhibit core cooling. For reactors with U-tube steam generators, procedures shall be developed to remove gases from the U-tubes since it is impractical to individually vent the thousands of U-tubes. 32. A single failure of a vent valve, power supply, or control system shall not prevent isolation of the vent path. On BWRs, block valves are not required in lines with safety valves used for venting. 43. Sufficient redundancy in the design shall be incorporated to minimize the probability of inadvertent actuation. Other methods to reduce the chances of inadvertent actuation, such as removing power or administrative controls, may be considered. 54. Since the reactor coolant system vent will be part of the reactor coolant system pressure boundary, all requirements for the reactor pressure