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) | |
Text
NRC-RES Fire PRA Workshop Module IV August 5-9, 2019 Rockville, MD NRC-RES/EPRI FIRE PRA METHODOLOGY Task 12 - Fire HRA Scoping Examples
Slide 2 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Outline 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 3 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Scoping Example
Slide 4 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD General assumptions for examples Actions have applicable plant emergency procedures and fire procedures Fire does not impact control room environment There is a full area burn out Adequate inventory in fire protection system (FPS)
The fire is not in the same location as the execution Note: Similar examples are being used to illustrate screening, scoping and detailed approaches, but scenario specifics may not be identical
Slide 5 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Operator fails to align FPS water to AFW pumps The auxiliary feedwater (AFW) pumps take water from the condensate store tank (CST).
With low low level in the tank, the operator would align the Fire Protection System (FPS ) to the pumps.
Consider the tank low low level (10%) would be reached in 10 hrs after the start of the fire.
This is a local action and the operator must manually open two valves.
Slide 6 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Operator fails to align FPS water to AFW pumps Cable tracing for CST level transmitters has been performed and the cues are not impacted by fire Timing information
- Tsw = 11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> - 10 hrs to low low level then 1 additional hr until 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 low level
- Tcog = 2 minutes
- Texe = 10 minutes
Slide 7 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 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 8 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Feasibility Timing analysis:
- Time available (60 mins) > Time required (12 mins)
Cues available to aid diagnosis
- Cable tracing was done on CST alarms Fire activity would not prevent the execution of the actions Enough crew members available to complete the action
Slide 9 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Time Margin To Tdelay Tcog Texe Tsw Start Cue received Crew diagnosis complete Action complete Action no longer beneficial Tavail 400 100
)
10 2
(
)
10 2
(
60 100
)
(
)
(
Margin Time
=
+
+
=
+
+
=
exe cog exe cog avail T
T T
T T
Slide 10 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Assessing Key Conditions & PSFs Condition Status Do the procedures match the scenario?
Yes Is the execution complexity high?
No Is the fire suppressed when the cue is received?
Yes Whats the time window (Tavail)?
60 min Is there any smoke or other hazardous elements in the action areas?
No Is the action area accessible?
Yes
Slide 11 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
Search Scheme
Slide 12 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
EXCR
Slide 13 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1A:
EXCR Lookup Table HEP Lookup Table Time Margin HEP HEP Label R
> 100%
0.002 EXCR12 50 - 99%
0.01 EXCR13
< 50%
1.0 EXCR14
Slide 14 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Operator fails to align FPS water to AFW pumps with failed alarm Same basic scenario as Example 1A
- The auxiliary feedwater (AFW) pumps take water from the condensate store tank (CST).
- When low low level in the tank is reached, the operator needs to align the FPS (fire protection system) to the pumps.
Cable tracing has not been 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 15 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Operator fails to align FPS water to AFW pumps with failed alarm Local action Timing information
- Tsw = 11 hrs - 10 hrs to low low level then 1 additional hr until 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 16 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 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 17 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Feasibility Timing Analysis:
- Time available (60 mins) > Time required (25 mins)
Cues available to aid recovery Fire activity would not prevent the execution of the actions Enough crew members available to complete the action
Slide 18 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Time Margin To Tdelay Tcog Texe Tsw Start Cue received Crew diagnosis complete Action complete Action no longer beneficial Tavail 140 100
)
10 15
(
)
10 15
(
60 100
)
(
)
(
Margin Time
=
+
+
=
+
+
=
exe cog exe cog avail T
T T
T T
Slide 19 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Assessing Key Conditions & PSFs Condition Status Do the procedures match the scenario?
Yes Is the execution complexity high?
No Is the fire suppressed when the cue is received?
Yes Whats the time window (Tavail)?
60 min Is there any smoke or other hazardous elements in the action areas?
No Is the action area accessible?
Yes
Slide 20 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Search Scheme
Slide 21 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Slide 22 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
Slide 23 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 1B:
SPI Lookup Table HEP Lookup Table Time Margin HEP HEP Label AT
> 100%
0.1 SPI27 50 - 99%
0.5 SPI28
< 50%
1.0 SPI29
Slide 24 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Operator fails to initiate bleed & feed The action to initiate bleed and feed will be done when the SGs are almost in dry out Cue to initiate bleed and feed is when 2 SGs are at less than 15% WR level In this case all indications of level are accurate With the main feedwater and auxiliary feedwater systems unavailable at the beginning of the initiating event, the SG goes to dry out in 45 minutes
Slide 25 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Operator fails to initiate bleed & feed MCR action Timing information
-TSW = 45 minutes
-Tdelay = 20 minutes
-Tcog = 3 minutes
-Texe = 8 minutes
Slide 26 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 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 27 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Feasibility
Timing Analysis:
Time available (25 mins) > Time required (11 mins)
Cues available to aid diagnosis All indications of SG level are accurate
Fire activity would not prevent the execution of the actions
Enough crew members available to complete the action
Slide 28 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Time Margin to Tdelay Tcog Texe Tsw Start Cue received Crew diagnosis complete Action complete Action no longer beneficial Tavail 127 100
)
8 3
(
)
8 3
(
25 100
)
(
)
(
Margin Time
=
+
+
=
+
+
=
exe cog exe cog avail T
T T
T T
Slide 29 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Assessing Key Conditions & PSFs Condition Status Do the procedures match the scenario?
Yes Is the execution complexity high?
No Is the fire suppressed when the cue is received?
No Whats the time window (Tavail)?
25 min Is there any smoke or other hazardous elements in the action areas?
No Is the action area accessible?
Yes
Slide 30 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
Search Scheme
Slide 31 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
INCR (part 1)
Slide 32 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
INCR (part 2)
Slide 33 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2A:
INCR Lookup Table HEP Lookup Table Time Margin HEP HEP Label E
> 100%
0.05 INCR14 50 - 99%
0.25 INCR15
< 50%
1.0 INCR16
Slide 34 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Operator fails to initiate bleed & feed and use of fire procedures The action to initiate bleed and feed will be done when the SGs are almost in dry out Cue to initiate bleed and feed is when 2 SGs are at less than 15% WR level In this case half of the indicators of SG level are failed and fire procedures must be used to identify which indicators are accurate With the main feedwater and auxiliary feedwater systems unavailable at the beginning of the initiating event, the SG goes to dry out in 45 minutes
Slide 35 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Operator fails to initiate bleed & feed and use of fire procedures MCR action Timing 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 36 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 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 37 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Feasibility
Timing 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 trust
Fire activity would not prevent the execution of the actions
Enough crew members available to complete the action
Slide 38 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Time Margin To Tdelay Tcog Texe TSW Start Cue received Crew diagnosis complete Action complete Action no longer beneficial Tavail 56 100
)
8 8
(
)
8 8
(
25 100
)
(
)
(
Margin Time
=
+
+
=
+
+
=
exe cog exe cog avail T
T T
T T
Slide 39 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Assessing Key Conditions & PSFs Condition Status Do the procedures match the scenario?
Yes Is the execution complexity high?
No Is the fire suppressed when the cue is received?
No Whats the time window (Tavail)?
25 min Is there any smoke or other hazardous elements in the action areas?
No Is the action area accessible?
Yes
Slide 40 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
Search Scheme
Slide 41 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
INCR (part 1)
Slide 42 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
INCR (part 2)
Slide 43 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Example 2B:
INCR Lookup Table HEP Lookup Table Time Margin HEP HEP Label E
> 100%
0.05 INCR14 50 - 99%
0.25 INCR15
< 50%
1.0 INCR16
Slide 44 Fire HRA - Scoping Analysis Examples Fire PRA Workshop 2019, Rockville, MD Questions?