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:
REVIEW RESPONSIBILITIES Primary - Containment Systems Branch (CSB)Containment Systems and Severe Accident Branch (SCSB)1 Secondary - NoneMaterials and Chemical Engineering Branch (EMCB)2 I. AREAS OF REVIEW CSBSCSB reviews the information presented in the applicant's safety analysis report (SAR) 3 concerning the control of combustible gases in the containment following a loss-of-coolant accident (LOCA) to assureensure conformance with the requirements of General Design 4 5 Criteria 5 , 41, 42 and 43. Following a loss-of-coolant accidentLOCA, hydrogen and oxygen 6 may accumulate inside the containment. The major sources of hydrogen and oxygen are: 1. a chemical reaction between the fuel rod cladding and steam, 7 2. the corrosion of aluminum and other materials by an alkaline spray solution, and 3. the radiolytic decomposition of the water in the reactor core and the containment sump. If excessive hydrogen is generated it may combine with oxygen in the containment atmosphere. For inerted containments, the potential exists for hydrogen to combine with oxygen generated following the accident. The CSBSCSB review includes the following general areas: DRAFT Rev. 3 - April 1996 6.2.5-2 1. The production and accumulation of combustible gases within the containment following a postulated loss-of-coolant accidentLOCA. 2. The capability to mix the combustible gases with the containment atmosphere and prevent high concentrations of combustible gases in local areas. 3. The capability to monitor combustible gas concentrations within containment. 4. The capability to reduce combustible gas concentrations within containment by suitable means, such as recombination, dilution, or purging. The CSBSCSB review specifically covers the following analyses and aspects of combustible gas control system designs: 1. An analysis of combustible gas (i.e., hydrogen and oxygen) production and accumulation within the containment following a loss-of-coolant accidentLOCA. 2. An analysis of the