Document: NRC Regulatory Guide
Document ID: 8291b9eb-e4a7-4806-8b5b-1deca2ff1fe2
Document Type: regulatory_guide
Title: Control Room Habitability at Light-Water Nuclear Power Reactors
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0207/ML020790125.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.196
CFR Part: 
CFR Title: 

Content:
ks to modify its licensing basis through a license amendment is not protected by the backfit as defined by 10 CFR 50.109, "Backfitting.” Backfitting occurs only when the NRC imposes a new or changed position on a licensee, which is not the case when a licensee voluntarily seeks an amendment. Plants were licensed with various trade-offs of conservatisms compensating for non-conservatisms in radiological dose analyses. The trade-offs for each plant were different. The NRC staff has integrated the accumulated technical knowledge to the year 2001 in this regulatory guide and has offered a package of more realistic analysis methods and limits along with reduced conservatism and appropriate reconciliation of nonconservatisms. The staff believes that only by implementing the integrated package as presented within the Regulatory Positions will the design bases be preserved. 2. DEMONSTRATING AND MAINTAINING CRH Regulatory Positions 2.1 through 2.7 provide guidance on the process of demonstrating and maintaining CRH. 5 2.1 Identification of the Licensing Bases for the CRE 2.1.1 Determination of the CRE Confirmation of a facility's ability to meet CRH requirements begins with the identification of the CRE. The CRE is usually defined by the licensee. The CRE encompasses the main control room and may encompass the alternate shutdown panel and other rooms and areas to which personnel access may be necessary to accomplish plant control functions in case of an accident. Typical CREs may include cable spreading rooms, process instrumentation rooms, switchgear rooms, a technical support center (TSC), the operations support center, controlled document rooms, process computer rooms, a kitchen and restrooms, and heating, ventilation, and air conditioning equipment rooms. A description of the CRE may be contained in a number of plant documents. These documents might include the Updated Final Safety Analysis Report (UFSAR), the original Final Safety Analysis Report (FSAR), the Safety