Document: NUREG-0800
Document ID: 545a669a-51a1-4b1f-9d90-78ee08ca0845
Document Type: srp
Title: COMBUSTIBLE GAS CONTROL IN CONTAINMENT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070463.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.2.5
CFR Part: 
CFR Title: 

Content:
e primary reviewer obtains and uses such input as required to assureensure that this review procedure is complete. The combustible gas control systems include systems for mixing the combustible gases, monitoring combustible gas concentrations, and reducing the combustible gas concentrations. In general, all of the combustible gas control systems should meet the design requirements for engineered safety features, as outlined in subsection II. The system description and schematic drawings presented in the safety analysis report should be sufficiently detailed to permit judgments to be made regarding system acceptability.37 1. CSBSCSB reviews the applicant's analyses of the production and accumulation of oxygen and hydrogen in the containment following postulated loss-of-coolant accidentsLOCA, to assureensure that the recommendations and guidelines of Regulatory Guide 1.7 have been followed. With regard to the extent of metal-water reaction to be considered, the combustible gas control system designs of some boiling water reactor plants with BWR6/Mark III containments have been evaluated and accepted on the basis of an assumed metal-water reaction involving one percent of the cladding mass. Since this assumption is conservative with respect to Regulatory Guide 1.7 (the Regulatory Guide would indicate about 0.7% reaction of the cladding mass in these cases), it will continue to be an acceptable basis for these plants, at the option of the applicants. As 38 necessary, the CSBSCSB will make confirmatory analyses of combustible gas production and accumulation. These analyses are done using the COGAP computer code, a description of which is attached as Appendix A to this SRP section. The safety analysis report should contain the required code input data. The purposes of, the analyses are: a. To confirm the predictions of hydrogen and oxygen generation appearing in the safety analysis report. b. To verify that the systems provided for combustible gas control are capable of