Document: NUREG-0800
Document ID: 80fe9eee-2d6e-4a7e-b7dd-ec23aab2d39f
Document Type: srp
Title: STRATEGIES AND GUIDANCE TO ADDRESS LOSS OF LARGE AREAS OF
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1211/ML121110138.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.4
CFR Part: 
CFR Title: 

Content:
ray strategies are required per NEI 06-12. One is “local spray” from the area surrounding the SFP and the other is “elevated spray” from other locations, such as from the ground or surrounding buildings. Some licensees failed to establish a “local spray” and others failed to establish an “elevated spray.” Some licensees who failed to establish an “elevated spray” strategy assumed that the portable spray strategies for reactors and containments, i.e., strategies in Sections 3.3.7 and 3.4.10 in NEI 06-12, were sufficient to replace the SFP “elevated spray.” The “portable spray” strategies and the “elevated spray” strategies have different requirements and different purposes. Staff Position The NRC staff expects that most, if not all, applicants will choose to implement the spray strategies described in Section 4.2.2 of NEI 06-12, Revision 3, which involve the use of multiple standpipes diversely located around the SFP and hard-piped to an external fire hose connection on the outside of the building. Those applicants that do not choose this approach and follow the approach taken by current operating plants described in Section 2.3.2 of NEI 06-12, Revision 3 must address “local spray” from the area 19.4-23 Revision 0 – May 2013 surrounding the SFP and “elevated spray” from other locations such as from the ground or surrounding buildings. 12. NEI 06-12, Revision 3 states that users must assure that 200 gpm of spray flow reaches the SFP and that the entire SFP is covered. During inspections, the NRC staff questioned how licensees had determined that 200 gpm was reaching the SFP and how they could be assured that the entire SFP was covered. Some licensees had performed tests to determine if they could spray an area the size of the SFP, but none had actually calculated or measured the spray flow to determine if 200 gpm had reached the SFP. At one site, the licensee had assumed that a flow rate of 218 gpm from the nozzle would be