Document: NUREG-0800
Document ID: 92e07546-68d7-4c8e-a984-7d1f1f4d882d
Document Type: srp
Title: EQUIPMENT AND FLOOR DRAINAGE SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550042.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.3.3
CFR Part: 
CFR Title: 

Content:
the control room uninhabitable. GDC 2 assures that all EFDS safety-related portions will continue to provide adequate drainage capacity during and following natural phenomena to accommodate postulated flooding events without water accumulation where it could jeopardize continued operability of safety-related equipment. In addition, these regulatory requirements assure that no system component failures will jeopardize the integrity of the reactor coolant pressure boundary, the capability to shut the reactor down and maintain it in a safe shutdown condition, or the capability to prevent or mitigate the consequences of accidents that could result in offsite radiation exposures. 2. GDC 4 requires that SSCs important to safety be designed to accommodate the effects of and be compatible with the environmental conditions of normal operation, maintenance, surveillance testing, and postulated accidents. For the EFDS, the purpose of GDC 4 is to assure the capability to provide the required drainage capacity to accommodate unanticipated flooding from pipe breaks, tank leaks, discharge from fire suppression systems, and other potential flooding sources. GDC 4 thus requires consideration in the design basis of the EFDS of the entire spectrum of flooding events, from relatively minor, operations-related, or testing-related events to postulated accidents. GDC 4 assures that safety-related equipment functions will not be impacted by undue water accumulations within the plant. 3. GDC 60 requires plants to be designed to control the release of radioactive materials in gaseous and liquid effluents. The EFDS must have sufficient capability and margin to collect and dispose of radioactive and nonradioactive liquid effluents for their controlled and safe processing. As radioactive liquid effluents require a treatment different from that for nonradioactive effluents, the EFDS design typically provides for two separate systems, one for collecting radioactive and the other for collecting