Document: NUREG-0800
Document ID: 8238d583-b5fc-4a78-9cf3-4407f130bbbd
Document Type: srp
Title: SYSTEM QUALITY GROUP CLASSIFICATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0631/ML063190003.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.2.2
CFR Part: 
CFR Title: 

Content:
up classification are considered to be acceptable normally only at valve locations, with the valve assigned the higher classification. A change in quality group classification with no valve present is normally considered acceptable only when it can be demonstrated that the safety function of the system is not impaired by a failure on the lower-classification side of the boundary. The following fluid systems important to safety for pressurized water reactor (PWR) and boiling water reactor (BWR) plants are examples of those that are reviewed by the staff with regard to quality group classification. Typical PWR and BWR system names are provided below, based on historical staff reviews of prior applications. It should be noted that systems whose function is important to safety in accordance with RG 1.26 and that are used in passive system light water reactor (LWR) designs or non-LWR designs may not be identified by these names. FLUID SYSTEMS IMPORTANT TO SAFETY FOR PWR PLANTS Auxiliary Feedwater System Boron Thermal Regeneration System1,2 Boron Recycle System1,2 Chemical and Volume Control System Combustible Gas Control System1,6 Compressed Air System1,2,6 Condensate Storage System1 Containment Cooling System Containment Isolation System6 Containment Purge System Containment Spray System Emergency Core Cooling System Emergency Diesel Engine Fuel Oil Storage and Transfer System6 Emergency Diesel Engine Cooling Water System Emergency Diesel Engine Starting System Emergency Diesel Engine Lubrication System Emergency Diesel Engine Combustion Air Intake and Exhaust System Equipment and Floor Drainage System2,6 Feedwater System3 Main Steam System3 Pressurizer Power-Operated Relief Valves (PORVs) (including associated components and block valves)6 Process and Post-Accident Sampling Systems3 Reactor Auxiliary Cooling Water Systems (e.g., Component Cooling Water and Essential Chilled WaterSystems)2 Reactor Coolant System Refueling Water Storage System2 Residual Heat Removal