16.2 - Severe Accident Analysis (RRC-B) - EDF Hinkley Point

SUB-CHAPTER : 16.2PRE-CONSTRUCTION SAFETY REPORTCHAPTER 16: RISK REDUCTION AND SEVEREACCIDENT ANALYSESPAGE : 119 / 295Document ID.No.UKEPR-0002-162 Issue 04SUB-SECTION 16.2.2.3 - TABLE 2Hydrogen distribution [Ref]Scenario5 cm (20 cm 2 )SB(LOCA)cold leg p.c.5 cm (20 cm 2 )SB(LOCA)hot leg f.s.c.7.5 cm (46 cm 2 )SB(LOCA)pressuriser f.s.c.5 cm (20 cm 2 )SB(LOCA)cold leg f.s.c.5 cm (20 cm 2 )SB(LOCA)cold leg f.s.c.with refloodMaximummass ofH 2present inthecontainment(kg)MaximumaverageH 2concentra-tion(% byvolume)Maximumsize ofthe 4% H 2plume(m 3 )Timewhen 4%plumereachesmaximumafter startof H 2release(s)Maximumsize ofthe 13%H 2 plume(m 3 )Timewhen 13%plumereachesmaximumafter startof H 2release(s)500 5 80000 2000 210 1000450 5.5 60000 2500 1000 100580 7 52000 3200 20000 1500580 8 74000 3500 9500 1500860 9.5 75000 2000 20000 15005 cm (20 cm 2 )SB(LOCA)p.c. cold leg 800 7 75000 600 5000 200with delayeddepressurisation(p.c.: partial cooldown, f.s.c.: fast secondary cooldown; shaded rows: bounding scenarios)