Document: NUREG-0800
Document ID: 1c401e6c-8c2d-47df-b05f-2978939cbd15
Document Type: srp
Title: CONTROL ROOM HABITABILITY SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550069.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.4
CFR Part: 
CFR Title: 

Content:
ardous gases. The organization responsible for the review of SRP Sections 2.2.1 and 2.2.2 will provide its findings to the organization responsible for ventilation and air filtration for its toxic gas estimates for use in the control room habitability analysis. There are three basic categories: Radioactive sources, toxic gases such as chlorine, and gases with the potential for being released inside confined areas adjacent to the control room. Evaluation of the relative locations of sources and airborne transport of toxic or otherwise potentially hazardous gases depends on the physical and meteorological characteristics of the site, and plant design and, thus, can be finalized only at the COL stage of review. A. Radiation Sources. The organization responsible for the review of design basis accident radiological consequence analyses will review SRP Section 15.6.5, Appendix A or SRP section 15.0.1 (for AST plants that implement 10 CFR 50.67) or SRP Section 15.0.3 (for future reactors) to determine the LOCA source terms that are routinely used to evaluate the radiation levels external to the control room envelope. Contamination pathways internal to the plant are examined to 6.4-15 Revision 3 - March 2007 determine their impact on control room habitability. Other DBAs are reviewed to determine whether they might constitute a more severe hazard than the LOCA. If appropriate, an additional analysis is performed for the suspect DBAs. See SRP Section 2.3.4. B. Toxic Gases. The organization responsible for the review of materials and chemical engineering will review and identify those toxic substances stored or transported in the vicinity of the site which may pose a threat to the plant operators upon a postulated accidental release. The method used to determine whether the quantity or location of the toxic material is such as to need closer study is described in Regulatory Guide 1.78. This guide also discusses the methods for analyzing the degree of risk and states, in