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:
is is the documentation that describes how the plant meets applicable regulations. Design bases are defined in 10 CFR 50.2. Regulatory Guide 1.186, “Guidance and Examples for Identifying 10 CFR 50.2 Design Bases" (Ref. 3), provides additional guidance. The design bases are a subset of the licensing bases. Thus, licensing bases will be used in this guide to refer to both. 4 1. Identification of the licensing bases for the (a) CRHS, (b) areas adjacent to the CRE, and (c) ventilation systems that serve or traverse the CRE and those adjacent to the CRE. 2. Determinations of whether the design, configuration, and operation of the systems and areas identified in action 1 are consistent with the licensing bases. 3. Determination of the performance characteristics for operating modes associated with radiological and hazardous chemical accidents. 4. Calculation of the radiological dose consequences. 5. Calculation of the hazardous chemical release consequences. 6. Assessment of whether a radiological, hazardous chemical, or fire challenge could result in the inability of the control room operators to control the reactor from either the control room or the alternate shutdown panel. 7. Maintenance and monitoring of the CRHS. 1.2 Applicability of Prior Licensing Basis3 The application of this regulatory guide may involve a licensee-initiated voluntary change to the licensing basis of the facility. To issue a license amendment on the basis of this guide, the NRC staff must make a current finding of compliance with regulations applicable to the amendment. The staff may find that new or unreviewed issues are created by a particular site-specific application of this guide, warranting review of past staff positions on a particular licensing basis. A licensee who voluntarily seeks 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