ML19212A731
| ML19212A731 | |
| Person / Time | |
|---|---|
| Issue date: | 07/31/2019 |
| From: | Office of Nuclear Regulatory Research |
| To: | |
| D. Stroup 415-1649 | |
| Shared Package | |
| ML19212A718 | List: |
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| Download: ML19212A731 (44) | |
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NRC-RES Fire PRA Workshop Module IVAugust 5-9, 2019Rockville, MD NRC-RES/EPRI FIRE PRA METHODOLOGYTask 12 -Fire HRA Scoping Examples Slide 2Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDOutline of the Presentation 1.Introduction to HRA 2.Overview of the EPRI/NRC Fire HRA Guidelines 3.Identification and definition of fire human failure events 4.Qualitative analysis 5.Fire HRA Application Experience 6.Quantitative analysis a)Screening b)Scoping c)Detailed EPRI approach & ATHEANA (detailed) 7.Recovery analysis 8.Dependency analysis 9.Uncertainty analysis Slide 3Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDScoping Example Slide 4Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDGeneral assumptions for examplesActions have applicable plant emergency procedures and fire proceduresFire does not impact control room environmentThere is a full area burn outAdequate inventory in fire protection system (FPS)The fire is not in the same location as the executionNote: Similar examples are being used to illustrate screening, scoping and detailed approaches, but scenario specifics may not be identical Slide 5Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Operator fails to align FPS water to AFW pumpsThe auxiliary feedwater(AFW) pumps take water from the condensate store tank (CST).With low lowlevel in the tank, the operator would align the Fire Protection System (FPS ) to the pumps.Consider the tank lowlowlevel (10%) would be reached in 10 hrsafter the start of the fire. This is a local action and the operator must manually open two valves. Internal events HEP = 5E
-3 Slide 6Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Operator fails to align FPS water to AFW pumpsCable tracing for CST level transmitters hasbeen performed and the cues are not impacted by fireTiming information
-T sw= 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br />
-10 hrsto low lowlevel then 1 additional hruntil tank is empty and pumps cavitate-Tdelay= 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />
-Time to reach low lowlevel-Tcog= 2 minutes
-Texe= 10 minutes Slide 7Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Minimum Criteria 1.Procedures
-Plant procedures covering each operator action being modeled-Support both diagnosis & execution of the action 2.Training -on the procedures and the actions 3.Availability and accessibility of equipment Slide 8Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:FeasibilityTiming analysis:
-Time available (60 mins) > Time required (12 mins)Cues available to aid diagnosis
-Cable tracing was done on CST alarmsFire activity would not prevent the execution of the actionsEnough crew members available to complete the action Slide 9Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Time Margin T o T delay Tcog Texe T swStartCuereceivedCrewdiagnosiscompleteActioncompleteAction nolongerbeneficial Tavail%400%100*)10 2 ()10 2 (60%100*)()( Margin Timeexecog execogavail T T T T T Slide 10Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Assessing Key Conditions & PSFsConditionStatusDo the procedures match the scenario?YesIs the execution complexity high?
NoIs the fire suppressed when the cue is received?YesWhat's the time window (Tavail)?60 min Is there any smoke or other hazardous elements in the action areas?
NoIs the action area accessible? Yes Slide 11Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:Search Scheme Slide 12Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:EXCR Slide 13Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1A:EXCR Lookup TableHEP Lookup TableTime Margin HEP HEP Label R>100%0.002EXCR12 50 -99%0.01EXCR13< 50%1.0EXCR14 Slide 14Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Operator fails to align FPS water to AFW pumps with failed alarmSame basic scenario as Example 1A
-The auxiliary feedwater(AFW) pumps take water from the condensate store tank (CST).
-When low lowlevel in the tank is reached, the operator needs to align the FPS (fire protection system) to the pumps.Cable tracing has notbeen done therefore assume that fire fails the CST alarm at the 10% level
-The cue is no longer an alarm in MCR. Assumed that the action would not occur (error of omission) and the spurious indication flowchart must be used!
-The fire procedure does direct the crew to locally check tank level to make sure there is enough inventory.
Slide 15Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Operator fails to align FPS water to AFW pumps with failed alarmLocal actionTiming information
-T sw= 11 hrs-10 hrsto low lowlevel then 1 additional hruntil tank is empty and pumps cavitate. -Tdelay= 2 hrs-Estimated time before the crew sends local operator to verify CST level. This action is low priority.
-Tcog= 15 minutes
-Time to determine CST level
-Texe= 10 minutes Slide 16Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Minimum Criteria 1.Procedures
-Fire procedures covering each operator action being modeled-Support both diagnosis & execution of the action 2.Training -on the procedures and the actions 3.Availability and accessibility of equipment Slide 17Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:FeasibilityTiming Analysis:
-Time available (60 mins) > Time required (25 mins)Cues available to aid recoveryFire activity would not prevent the execution of the actionsEnough crew members available to complete the action Slide 18Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Time Margin T o T delay Tcog Texe T swStartCuereceivedCrewdiagnosiscompleteActioncompleteAction nolongerbeneficial Tavail%140%100*)10 15 ()10 15 (60%100*)()( Margin Timeexecog execogavail T T T T T Slide 19Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Assessing Key Conditions & PSFsConditionStatusDo the procedures match the scenario?YesIs the execution complexity high?
NoIs the fire suppressed when the cue is received?YesWhat's the time window (Tavail)?60 min Is there any smoke or other hazardous elements in the action areas?
NoIs the action area accessible? Yes Slide 20Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:Search Scheme Slide 21Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:SPI Slide 22Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:SPI Slide 23Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 1B:SPI Lookup TableHEP Lookup TableTime Margin HEP HEP Label AT>100%0.1SPI27 50 -99%0.5SPI28<50%1.0SPI29 Slide 24Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Operator fails to initiate bleed & feed The action to initiate bleed and feed will be done when the SGs are almost in dry outCue to initiate bleed and feed is when 2 SGs are at less than 15% WR levelIn this case all indications of level are accurateWith the main feedwater and auxiliary feedwater systems unavailable at the beginning of the initiating event, theSG goes to dry out in 45 minutes Slide 25Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Operator fails to initiate bleed & feed MCR actionTiming information
-TSW = 45 minutes
-Tdelay = 20 minutes
-Tcog = 3 minutes
-Texe= 8 minutes Slide 26Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Minimum Criteria 1.Procedures
-Plant procedures covering each operator action being modeled-Support both diagnosis & execution of the action 2.Training -on the procedures and the actions 3.Availability and Accessibility of Equipment Slide 27Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:FeasibilityTiming Analysis:
-Time available (25 mins) > Time required (11 mins)Cues available to aid diagnosis
-All indications of SG level are accurateFire activity would not prevent the execution of the actionsEnough crew members available to complete the action Slide 28Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Time Margin t o T delay Tcog Texe T swStartCuereceivedCrewdiagnosiscompleteActioncompleteAction nolongerbeneficial Tavail%127%100*)8 3 ()8 3 (25%100*)()(Margin Timeexecog execogavail T T T T T Slide 29Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Assessing Key Conditions & PSFsConditionStatusDo the procedures match the scenario?YesIs the execution complexity high?
NoIs the fire suppressed when the cue is received?NoWhat's the time window (Tavail)?25 min Is there any smoke or other hazardous elements in the action areas?
NoIs the action area accessible? Yes Slide 30Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:Search Scheme Slide 31Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:INCR (part 1)
Slide 32Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:INCR (part 2)
Slide 33Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2A:INCR Lookup TableHEP Lookup TableTime Margin HEP HEP Label E>100%0.05INCR14 50 -99%0.25INCR15< 50%1.0INCR16 Slide 34Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Operator fails to initiate bleed & feed and use of fire proceduresThe action to initiate bleed and feed will be done when the SGs are almost in dry outCue to initiate bleed and feed is when 2 SGs are at less than 15% WR levelIn this case half of the indicators of SG level are failed and fire procedures must be used to identify which indicators are accurateWith the main feedwater and auxiliary feedwater systems unavailable at the beginning of the initiating event, theSG goes to dry out in 45 minutes Slide 35Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Operator fails to initiate bleed & feed and use of fire procedures MCR actionTiming information
-TSW = 45 minutes
-Tdelay = 20 minutes
-Tcog = 8 minutes
-additional time than standard bleed & feed due to using multiple procedures.
-Texe= 8 minutes Slide 36Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Minimum Criteria 1.Procedures
-Fire procedures covering each operator action being modeled-Support both diagnosis & execution of the action 2.Training -on the procedures and the actions 3.Availability and accessibility of equipment Slide 37Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:FeasibilityTiming Analysis:
-Time available (25 mins) > Time required (16 mins)Cues available to aid diagnosis
-Some indications of SG level are accurate
-Fire procedures used to determine which indicators to trustFire activity would not prevent the execution of the actionsEnough crew members available to complete the action Slide 38Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Time Margin T o T delay Tcog Texe T SWStartCuereceivedCrewdiagnosiscompleteActioncompleteAction nolongerbeneficial Tavail%56%100*)8 8 ()8 8 (25%100*)()( Margin Timeexecog execogavail T T T T T Slide 39Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Assessing Key Conditions & PSFsConditionStatusDo the procedures match the scenario?YesIs the execution complexity high?
NoIs the fire suppressed when the cue is received?NoWhat's the time window (Tavail)?25 min Is there any smoke or other hazardous elements in the action areas?
NoIs the action area accessible? Yes Slide 40Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:Search Scheme Slide 41Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:INCR (part 1)
Slide 42Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:INCR (part 2)
Slide 43Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MDExample 2B:INCR Lookup TableHEP Lookup TableTime Margin HEP HEP Label E>100%0.05INCR14 50 -99%0.25INCR15< 50%1.0INCR16 Slide 44Fire HRA -Scoping Analysis ExamplesFire PRA Workshop 2019, Rockville, MD Questions?