ML072780167

August 2007 - Transition to National Fire Protection Association (NFPA) 805 - Pilot Observation Target Selection - Progress Energy - Briefing Materials/Meeting Handouts

ML072780167
Person / Time
Site:	Harris
Issue date:	08/07/2007
From:	Thompson S Nuclear Generation Group, Progress Energy Co
To:	Office of Nuclear Reactor Regulation
Oudinot D
Shared Package
ML072830337	List: ML072780114 ML072780118 ML072780120 ML072780124 ML072780126 ML072780133 ML072780138 ML072780144 ML072780152 ML072780155 ML072780167 ML072780214 ML072780267 ML072780284 ML072780319 ML072780325 ML072830283 NEI 04-02, August 2007 - Transition to National Fire Protection Association (NFPA) 805 - NEI 04-02 FAQs Pathway to Resolution - Progress Energy - Briefing Materials/Meeting Handouts
References
Download: ML072780167 (9)

Text

NFPA 805 Transition August Pilot Observation Target Selection Sarah Thompson, Fire Protection Engineer August 7, 2007 Bethesda, MD

NFPA 805 Target Selection Introduction O Iterative Approach O Fire PRA scenarios Z Full compartment and ignition source basis Z Start with scoping results Z Include transient Z More refined analysis as needed O Change Evaluations Z Start with Fire PRA scenario results Z Add detail as needed to support evaluations O Document analysis results in common calc Z Only includes detail beyond scoping level Page 2

NFPA 805 Target Selection Fire PRA Scenario Scoping Recap O Purpose - NUREG/CR-6850 Z Screen out those fixed ignition sources that do not pose a threat to the targets within a specific fire compartment, and Z To assign severity factors to unscreened fixed ignition sources O Zone of Influence (ZOI) Determination Z NRC Fire Dynamics Tools (FDTs)

O Walkdowns by Source to Identify Targets Z Collected target data, where targets included conduits, plan points, cable trays, other sources, and intervening combustibles O Source-Target Database Z Multiple HRR Page 3

NFPA 805 Target Selection Fire PRA Scenario Refinements O NUREG/CR-6850 Methods for Reducing ZOI Z Double-wall cabinets with air gap - limits horizontal flame propagation Z Non-vented cabinets with multiple points of contact -

flame propagation limited O Addressing HGL Z Screen based on the most conservative of the MQH natural ventilation and Beyler closed door methods O Examples from the supporting calculation Z MCC Example w/ FDTs Z MQH/Beyler HGL Screen Z Transient, Detailed Flame Spread Tool w/ CFAST Page 4

NFPA 805 Target Selection Treatment of Transients O Transient Exclusion Zones Z Do not postulate specific transient fires for change evaluations Z PRA addresses potential breakdown of administrative controls O Non-Exclusion Zones Z Postulate transients fire scenarios based on change evaluations needs Z PRA placement of transients same as that for exclusion zones Page 5

NFPA 805 Target Selection Change Evaluation Support O Change Evaluation Target Selection Z Fixed ignition sources that could directly impact the targets of concern based on physical location. Target data captured in PRA database - refine as needed.

Z Fixed ignition sources that could remotely impact the targets of concern via flame spread or fire propagation.

Z Fixed ignition sources that could remotely impact the targets of concern through generation of a hot gas layer.

Z Transient ignition sources, in addition to those in the PRA database, are postulated when needed.

O Task iteration is expected Z As we develop more data about each fire scenario we can better determine the need for additional data to address the issues.

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NFPA 805 Target Selection Data Packaging O Most of data is in the PRA database O Refinements for select scenarios are in a calculation by compartment/fire area O Engineering review process used for calculation O Quality is driven by NUREG-1824, Verification and Validation of Selected Fire Models for Nuclear Power Plant Applications Page 7

NFPA 805 Target Selection Closing O Where are we now?

Z Completed initial target data collection for fixed ignition sources Z Finalizing PRA target selection for transient ignition sources Z Performing ZOI refinement Z Scenario selection and fire modeling using simple tools as a first cut O Whats next?

Z Use risk input to have a focused approach on more detailed and complex modeling efforts Page 8

NFPA 805 Target Selection Questions?

Comments?

Concerns?

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