Document: NUREG-0800
Document ID: bcc615f1-3f65-4757-994f-88cc8fe800d5
Document Type: srp
Title: should still be met.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070473.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.5.1
CFR Part: 
CFR Title: 

Content:
ment building atmosphere may be considered a single, well-mixed space if the spray covers regions comprising at least 90% of the containment building space and if a ventilation system is available for adequate mixing of any unsprayed compartments. d. Spray Nozzles The design of the spray nozzles is reviewed to confirm that the spray nozzles are not subject to clogging from debris entering the recirculation system through the containment sump screens. e. Containment Sump Mixing The mixing of the spray water containing any chemical additive and water without additive (such as spilling ECCS coolant) in the containment sump is reviewed. The areas of the containment building that are exposed to the spray but are without direct drains to the recirculation sump (such as the refueling cavity) are considered. The reviewer confirms that the required sump solution concentrations are achieved within the appropriate time intervals. The pH of the sump solution should be reviewed in regard to iodine re-evolution, using the criteria given in subsection II.1.g and the procedure in subsection III.4.c.(2). f. Storage of Additives The design of any additive storage tank is reviewed to establish whether heat tracing is required to prevent freezing or precipitation in the tank. The reviewer determines whether an inert cover gas is provided for the tank to prevent reactions of the additive with air, such as the formation of sodium carbonate by the reaction of sodium hydroxide and carbon dioxide. Alternatively, the reviewer verifies by a conservative analysis that an inert cover gas is not required. g. Single Failure The system schematics are reviewed by inspection, postulating single failures of any active component in the system, including inadvertent operation of valves that are not locked open. The review is performed with respect to the fission product removal function, considering conditions that could result in fast as well as slow injection of the spray solution. DRAFT Rev. 3 -