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Summary of 980630 Meeting W/Bwrog App R Committee to Discuss post-fire Safe Shutdown Electrical Circuit Analysis Issues, Status of BWROG Activities & Future BWROG Activities
	ML20237C191
Person / Time
Issue date:	08/13/1998
From:	Joshua Wilson; NRC (Affiliation Not Assigned)
To:	Essig T; NRC (Affiliation Not Assigned)
References
	PROJECT-691 NUDOCS 9808210014
	Download: ML20237C191 (150)
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August 13,1998 MEMORANDUM TO:

Thomas H. Essig, Acting Chief Generic issues and Environmental Projects Branch Division of Reactor Program Management, NRR I

FROM:

James H. Wilson, Senior Project Manag

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Standardization Project Directorate Division of Reactor Program Management, RR

SUBJECT:

SUMMARY

OF MEETING HELD ON JUNE 30,1998, WITH THE BWROG APPENDIX R COMMITTEE I

l On June 30,1998, the staff participated in a public meeting of the Boiling Water Reactor Owners' Group (BWROG) Appendix R Committee. The purpose of this meeting was to discuss post-fire

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safe shutdown electrical circuit analysis issues, the status of BWROG activities, and future j

BWROG activities. A list of attendees and their affiliations is provided as Attachment 1.

I The agend,a for the meeting is provided as Attachment 2. Section 3 (Circuit Analysis Guidance) and Section 7 (Definitions) of a planned BWROG document entitled " Generic Guidance for Post-fire Safe Shutdown Circuit Analysis Assessment" were discussed in detail during the meeting.

This draft materialis provided as Attachment 3.

The BWROG Appendix R Committee made a brief presentation on each of the agenda items. A brief summary of the points of agreement for the June 30th meeting has been provided by the BWROG Appendix R Committee and is provided as Attachment 4.

During the discussions and in response to BWROG Committee questions, the NRC staff made the following points:

I Licensee Event Reports and inspection results indicate that some post-fire safe shutdown l

e circuits were not adequately protected at some reactor plants, apparently due to assumptions made in the licensees' circuit analyses. Therefore, the staff has identified post-fire safe shutdown circuit analysis as a potential generic issue.

e Generic Letter 86-10, Answer 5.3.10, taken in context with Question 5.3.10, was intended to set lower bounds on attemative and dedicateJ post-fire safe shutdown capability desian capacity (e.g. minimum pump flow rates), but not intended to limit assumed cable fire damage.

In addition to the background documents already identified by the BWROG Appendix R Committee, it should consider the Appendix R Statements of Consideration in developing l

the BWROG positions on post-fire safe shutdown circuit analysis should be considered.

The NRC staff is currently developing a comprehensive fire protection regulatory guide.

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One objective of the regulatory guide is to consolidate fire protection guidance and resolve any conflicting guidance, o

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J The BWROG Appendix R Committee should review Generic Letter 8610, Question 3.8.3 j

e and Question 5.1.2 regarding the terms " redundant,"" normal," and " preferred" safe shutdown trains, equipment and components, versus attemative safe shutdown equipment.

The BWROG Appendix R Committee stated that specific BWROG positions on post-fire safe shutdown ciwuit analysis have yet to be developed, but that its goal was to develop positions that would both address compliance with NRC regulations and facilitate consistent regulatory compliance by BWR licensees. The NRC staff requested that the BWROG Appendix R committee provide the staff with a description of its plan to develop its positions and guidance.

The BWROG Appendix R Committee stated that it planned to submit its document to the NRC during the second quarter of CY 1999 as a non-proprietary topical report for NRC review and approval.

The BWROG Appendix R Committee stated that it intends to treat all future guidance document draft material as proprietary (until formal submittal as a non-proprietary topicas report). The staff stated that it would be necessary for the NRC to make a proprietary finding for the in-process guidance document material, and that such a finding would be necessary prior to NRC staff participation in future meetings to discuss the draft material. The BWROG Subcommittee agreed to look into the requirements for obtaining a proprietary finding.

George Stramback, of General Electric, was designated as the BWROG point of contact for coordination ofinteractions. Leon Whitney, of the Plant Systems Branch, NRR, was designated as the corresponding NRC point of contact. It was agreed that Fred Emerson of the Nuclear Energy Institute would receive a courtesy copy of all correspondence between the points of contact.

The staff and the BWROG representatives agreed that meetings such as this one are a valuable means of communication, providing an opportunity for feedback between the industry and the staff. The BWROG Appendix R Committee intends to request by letter that the draft BWROG material discussed in these meetings be designated as proprietary. However, it was agreed that any final document submitted formally for NRC review will not be proprietary.

Project No. 691 Attachments: As stated cc w/atts: See next page Distribution:

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NAME DATE 8/S/98 8P3/98 8/13/98 Afb 98

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2-The BWROG Appendix R subcommittee should review Generic Letter 86-10, Question 3.8.3 and Question 5.1.2 regarding the terms " redundant,"" normal," and " preferred" safe shutdown trains, equipment and components, versus alternative safe shutdown equipment.

The BWROG Appendix R subcommittee stated that specific BWROG positions on post-fire safe shutdown circuit analysis have yet to be developed, but that its goal was to develop positions that would both address compliance with NRC regulations and facilitate consistent regulatory comphnce by BWR licensees. The NRC staff requested that the BWROG Appendix R com;. tee provide the staff with a description of its plan to develop its positions and guidance.

The BWROG Appendix R subcommittee stated that it planned to submit its document to the NRC during the second quarter of CY 1999 as a non-proprietary topical report for NRC review and approval.

The BWROG Apper. dix R subcommittee stated that it intends to treat all future guidance document draft material as proprietary (until formal submittal as a non-proprietary topical report).

The staff stated that it would be necessary for the NRC to make a proprietary finding for the.n-process guidance document material, and that such a finding would be necessary prior to NRC staff participation in future meetings to discuss the draft material. The BWROG Subcommittee agreed to look into the requirements for obtaining a proprietary finding.

George Stramback, of General Electric, was designated as the BWROG point of contact for coordination of interactions. Leon Whitney, of the Plant Systems Branch, NRR, was designated as the corresponding NRC point of contact. It was agreed that Fred Emerson of the Nuclear Energy Institute would receive a courtesy copy of all correspondence between the points of contact.

The staff and the BWROG representatives agreed that meetings such as this one are a valuable means of communication, providing an opportunity for feedback between the industry and the staff. The BWROG Appendix R subcommittee intends to request by letter that the draft BWROG material discussed in these meetings be designated as proprietary. However, it was agreed that any final document submitted formally for NRC review will not be proprietary.

Project No. 691 Attachments: As stated cc w/atts: See next page Distribution:

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OFFICE PGEB (A)SC:PGEB BCMB (A)BC:PGEB NAME JWilso[

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} AMM TEssig DATE 8/p/98 8/ /98 8/t3/98 8/ /98 OFFICIAL RECORD COPY i

Project No. 691 Boiling Water Reactor Owners' Group cc:

Thomas J. Rausch, Chairman W. Glenn Warren Boiling Water Reactor Owners' Group Southern Nuclear / Georgia Power Commonwealth Edison Company E.I. Hatch Nuclear Plant Nuclear Fuel Services PO Box 1295 M/C B052 1400 Opus Place,4th Floor ETWill Birmingham, AL 35201 Downers Grove, IL 60515 Carl D. Terry Dennis B. Townsend Vice President, Nuclear Engineering GE Nuclear Energy Niagara Mohawk Power Corporation M/C 182 Nine Mile Point-2 175 Curtner Avenue PO Box 63 San Jose, CA 95125 Lycoming, NY 13093 Drew B. Fetters Thomas A. Green PECO Energy GE Nuclear Energy Nuclear Group Headquarters Mail Code 182 MC 62C-3 175 Curtner Avenue 965 Chesterbrook Blvd.

San Jose, CA 95125 Wayne, PA.19087 John Hosmer Commonwealth ' Edison Executive Towers,4th Floor 1400 Opus Place Downers Grove, IL 60515 George T. Jones Pennsylvania Power & Light MC A6-1 Two North Ninth Street Allentown, PA 18101 Lewis H. Sumner Southern Nuclear / Georgia Power E.1. Hatch Nuclear Power Plant 40 invemess Parkway PO Box 1295 Birmingham,GA 35201 John Kelly New York Power Authority 14th Floor Mail Stop 14K Centroplex Building 123 Main Street White Plains, NY 10601

LIST OF ATTENDEES AT MEETING WITH THE BWROG APPENDlX R COMMITTEE HELD IN BALTIMORE, MARYLAND ON JUNE 30,1998 NAME AFFILIATION L. Marsh NRC L. Whitney NRC K. West NRC P. Madden NRC C. Bajwa NRC K. Sullivan NRC B. Matthews BWROG G. Stramback BWROG V. Bacanskas BWROG

AGENDA Public Meeting Between NRC Staff and BWR Owners Group June 30,1998 9:30 p.m. - 3:30 p.m.

Baltimore Marriott inner Harbor 9:30 Introduction (BWROG and NRC) 9:35 Review timeline of completed work and discuss process for resolution ofissues (BWROG and NRC) 10:00 Baselining - Identification of available regulatory guidance documents (BWROG)

- Feedback on what documents may have been overlooked (NRC) 10:30 Break 10:45 NRC-identifiedissues (NRC) 11:15 Discussion of definitions (BWROG and NRC) 12:00 Lunch 1:00 Continue discussion of definitions (BWROG and NRC) i 2:30 Break 2:45 Continue discussion of definitions (BWROG and NRC) 3:20 Summary and plans for next meeting (BWROG and NRC) 3:30 Adjoum

DRAFT BOILING WATER REACTOR OWNERS' GROUP GENERIC GUIDANCE FOP. BWR POST FIRE SAFE SIIUTDOWN CIRCUIT ANALYSIS ASSESSMENT

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TABLE OF CONTENTS Page Executive Summary 1.0 Introduction

1.1 Background

1.2 Purpose of Document i

2.0 Overview 2.1 Methods and Systems 2.2 Equipment and Com ts 2.3 Circuit Selection Ev tion

-2.4 ~ ~ Coping.

ompli ce rateg' s 2.5 Fire,

a an ep ti Requ' nts

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3.1 Su ary o eg atio 3.2 Re atory nd dance Time Line 3.3 Po o

n Regulations and Guidance 3.4 R

atory Compliance 4.0 Safety Assessment 4.1 Introduction 4.2 Scope 4.3 Discussion 4.4 Defense in Depth 5.0 Conclusions 1

6.0 References 7.0 Definitions 8.0 Assumptions W

i ATTACHMENT 3

DRAFT BOILING WATER REACTOR OWNERS' GROUP GENERIC GUIDANCE FOR BWR POST FIRE SAFE SHUTDOWN CIRCUIT ANALYSIS ASSESSMENT

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Eaga Appendix A Operating Experience A.1 Pre-Appendix R A.2 Post Appendix R I

Appendix B Effects of Brown's Ferry Fire Appendix C Fire Protection Improvements Sine rowT F

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DRAFT BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.0 CIRCUIT ANALYSIS GUIDANCE The Nuclear Regulatory Commission's basic fire protection regulation for commercial nuclear power plants is Section 50.48 of 10 CFR PART 50 " Fire Protection." Section 50.48 references General Design Criterion (GDC) 3 of Appendix A to 10 CFR Part 50," Fire protection," Appendix R to 10 CFR Part 50" Fire Protection Program for Nuclear Power Facilities Operating Prior to January 1,1979," and various NRC fire protection guidance documents. Specifically, Section 50.48(a) states that each operating nuclear p~ower plant must have a fire protection plan that satisfies GDC 3, and Section 50.48 (b) states that Appendix R to 10 CFR 50 establishes fire protection features required to satisfy GDC 3 with respect to certain generic issues for nuclear power plarits licensed to operate prior to January 1,1979. Whilid'ppendix R is applicable only to fa'eilities that commenced operation prik to January 1,1979, facilities comniencing operation

,on or after January 1,197,9, are bound to satisfy the criteria of Appendix R through license conditions or^ licensing commitments.

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NRC requirements'and guidance for fire prbtection are contained in a number of documentse And in maily ca. des, the staff has not issued detailed guidance on specific issues, or' conflicting guidance exists. Therefore, the purpose of this section is'to com' pile alie existing guidance and requirements and provide BWROG interpretations of the requirements, clarifications of conflicting guidance and provide the necessary criteria to determine generic compliance. However, the extent to which these requirements and guidance are applicable to a specific plant depends upon the age of the plant and the commitments established by the licensee in developing its fire protection plan. Therefore, in determining compliance, each plant is the responsible for comparing the BWROG interpretations with their specific' commitments.

3.1 POSITIONS ON REGULATIONS AND GUIDANCE A.

Purpose of Position Statements In many cases, the NRC staff has not issued guidance on specific positions or the guidance that was issued after licensees had expended considerable effort in addressing issues. For this reason, the Boiling Water Reactor Owners' Group (BWROG) developed statements of positions relative to Rev.G 6/24/98 3-1 l

DRAFT BWROG I

L Generic Guidance for Post Fire Safe

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Shutdown Circuit Analysis Assessment major 10 CFR 50, Appendix R topics. The BWROG positions consist of the following:

A statement of the applicable regulations.

A statement of the applicable guidance.

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A statement of the conflicting guidance.

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f" A statement of the BWROG position to meet the requirements.

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A statement of the criteria to meet the BWROG position.

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Twenty-three. position statements arejresented in this section. Each

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Fire Area Defmition

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- Fire Protection of Safe Shutdown Capability i

3.1.4 Hot Shutdown / Cold Shutdown Definitions j

3.1.5 Redundant, Alternative (Alternate) or Dedicated Shutdown Capability 3.1.6 Control Room Fire Considerations 3.1.7 Free of Fire Damage 3.1.8

' Functional Failure States

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3.1.9 Circuit Failure Modes 3.1.10 Associated Circuits

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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis' Assessment 3.1.11 Hot Short Duration l

3.1.12 Ungrounded DC Control Circuits 3.1.13 High/ Low Pressure Interface 3.1.14 Vessel Level above Top of Active Fuel

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3.1.23 Suppression and Detection GL 85-01 and GL 86-10 are almost identical in intent and content; therefore, only the i

statement in GL 86-10 is listed unless a portion of GL 85-01 is different from GL 86-10 in intent or ifit provides a more definitive description of the position.

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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.1 SAFE SHUTDOWN ANALYSIS A.

Regulations 10 CFR S0. Appendix R. Section HB.(2). General Requirements

" determine the consequences of fire in any location in thi 51 ant on the 1

ability to safely shut down the reactor or on the ability to. minimize and control the release of radioactivity to the environment;..."-

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releases to the environment in the. event of a fire.

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and reac,tdr sydei$s engineers to (1) consider potential in situ and transient fiie h,azards; (2) determine the consequences of fire in any location in the

, plant on the ability to safely shut down the reactor or on the ability to minimize and control the release of radioactivity to the environment; and (3) specify measures for fire prevention, fire detection, fire suppression, i

and fire containment and alternative shutdown capability as required for

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each fire area containing structures, systems, and components important to safety that are in conformance with NRC guidelines and regulations.

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DRAFT BWROG Generic Guidance for Post Fire Safe

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Shutdown Circuit Analysis Assessment Ge. eric Letter 81-12. Enclosure 1. StaffPosition. Safe Shutdown Capability

"...the staff has required that an adequate safe shutdown analysis be performed. This evaluation includes the identification of the systems required for safe shutdown and the location of the system compor.ents in the plant.

Where it is determined by this evaluation that safe shutdown components of both redundant divisions are located in the same fire area,1he licensee is required to demonstrate that a postulated fire will notldaniage both divisions or provide alternate shutdown capability..." ~

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Generic Letter 86-10, Section C. Documentation Requiled to Demonstrate Compliance. Also Generic Letter 85-01. Enclosure 2. Implementation ofFire Protection Requirements. Sectidn C, Documentation Required to Demonstrate

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"The ' Interpretation 55docunient attach t6 this letter states that, where thel licensee' chooies liot to s'eek,p'io~r NRC review and approval of, for

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r exhmple, affire a$ea bbund5ry, an evaluation must be performed by a fire prbtection engidee,r (aidsted by others as needed) and retained for future f

NRC audit. Ev'itluations of this type must be written and organized to t

fadilitad review by a person not involved in the evaluation. Guidelines for

,Jvlift'such an evaluation should contain may be found in: (1) Section B of Appendix R and (2) Section C.I.b of Branch 'I echnical Position (BTP)

CMEB 9.5-1 Rev. 2 dated July 1981. All calculations supporting the evaluation should be available and all assumptions clearly stated at the outset. The NRC intends to initiate enforcement action where, for a given fire area, compliance wit 8 Appendix R is not readily demonstrable and the licensee does not have available a wrisen fire hazard analysis for the area.

The term 'readily demonstrable' includer situations where compliance is apparent by observation of the potential fi e hazard and the existing r

protective features."

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Conflicting Guidance Rev.G 6/24/98 3-6

DRAFT BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.2 FIRE AREA DEFINITION A.

Regulations Not specifically addressed in any regulation.

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Guidance NUREG-0800, SRP. Section 9.51. Section B.3. Establishment and Use of Fire Areas j

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-equipineht.-Fire aitas,should be established to separate redundant safety divisions and isolate safety-related systems from fire hazards in nonsafety-(..

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redundanpcablek will llelp to avoid loss of redundant safety-related cables.

Separatodire areds should also be employed to limit the spread of fires betweeEcomponents that are major fire hazards within a safety division.

,,Where redundant systems cannot be separated by fire barriers, as in containment and the control room, it is ne, essary to employ other measures to prevent a fire from causing the loss of function of safety-related systems.

Within fire areas containing components of a safety-related system, special attention should be given to detecting and suppressing fires that may adversely affect the system. Measures that may be taken to reduce the effects of a postulated fire in a given fire area include limiting the amount of combustible materials, installing fire-resistant construction, providing fire rated barriers for cable trays, installing fire detection systems and fixed fire suppression systems, or providing other protection suitable to the installation. The fire hazard analysis will be the mechanism to determine that fire areas have been properly selected.

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DRAFT BWROG Generic Guidance for Post-Fite Safe

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Shutdown Circuit Analysis Assessment NUREG-0800. SRP, Section 9.5.1, Section B.4. Definitions Fire Area - that portion of a building or plant that is separated from other areas by bmr.idary fire barriers.

Fire Bauier - those components of construction (walls, floors, and their supports), including beams, joists, columns, penetration seals, or closurcs, fire doors, and fire dampers that are rated by approving lab ~ oratories in hours of resistance to fire and are used to prevent the spre'ad of fire.

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bounded toyithsEnd 'the hazards associated with the area and, as neces'sary, to' prot'ec'tlimportaAt eqitipn>e'nt hithin the area from a fire

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outhide theIsrea. fin order to' meet:the regulation, fire area boundaries need nofbe comjletely sealed f1'odr-to-ceiling, wall-to-wall boundaries.

Hciwever,All un# sealed ~ openings should be identified and considered the evaluatink thofffdctiveness of the overall barrier. Where fire area boundnies are not wall-to-wall, floor-to-ceiling boundaries with all jerfe'trations sealed to the fire rating required of the boundaries, licensees i

must perform an evaluation to assess the adequacy of fire boundaries in

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their plants to determine if the boundaries will withstand the hazards associated with the area. This analysis must be performed by at least a fire protection engin;er and,ifrequired, a systems engineer. Although not required, licensees may stibmit their evaluations for staff review and concurrence. However, if certain cable penetrations were identified as open SER items at the time Appendix R became effective,Section III.M of the rule applies (see 10 CFR 50.48(b)), and any variation from the requirements of Section III.M requires an exemption. In any event, these analyses must be retained by the licensees for subsequent NRC audits."

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DRAFT BWROG l

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Generic Guidance for Post-Fire Safe -

Shutdown Circuit Analysis Assessment reasonable assurance that the limits of fire or fire suppressant damage to shutdown systems have been defined.

In many plant areas, however, the erection of physical barriers between redundant shutdown systems is precluded by the location of cable trays, HVAC ducts and other plant features. In such situations, the staff has accepted, in concept, the use of an automatic fire suppression system which discharges a " water curtain" across the boundary areas s'eparating the redundant systems. The design of such j' water curtain ~s" has not been codified, i.e., the National Fire Protection Association Standards do not address the use of fire suppression systems".for s' ch applications.

u However, the staffis. currently working with several applicants and licensees to define'desijn requirenients wlilih 'will sati4fy mutual concerns. The staff's present position is that such systems should feature

_ -< lose ' space', oped-head sprinklers'with,Nater dischargslnitiated by,

d tripping a delugejvalve activated by cross' zoned smoke detectors. Where smok'e prop"agati6idhes not reprehnt a'Tiazard to redundant shutdown

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systems, a close4pah clos 5-head s'prinkler system may be deemed ac$eptableAWh$re such " Mater curtains" are used the operation of such systems should,$o) end' anger safety systems on either side of the " water curtains #

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~~Section 3.1.1. Fire Area Definition. Also Generic Letter 85-01. Enclosure~~

~~6. Appendix R Questions and Answers. Section 3.1.1. Fire Area Definition QUESTION c'~~
c n "Section III.G states the fire protection features required for cables and equipment or redundant trains of systems seqdired)to achieve and maintain hot shutdown that are located within the same fire area..Is the fire area of Section III.G, the same fire area referred td.in BTP APCSB 9.5-1, Appendix A; and the supplementary guida'nce df September 1976?"
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"... defined a fire area as:
that portion of a building that is separated from other areas by boundary fire barriers (walls, floors, or roofs) with any openings or penetrations protected with seals or closures having a fire resistance i
rating equal to that of the barrier..."
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DRAFT BWROG Generic Guidance for Post-Fire Safe
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Shutdown Circuit Analysis Assessment SECY 83-269. Attachment B. NRC StaffPositions on Certain Requirements ofAppendix R to 10 CFR 50. Fire Areas StaffPosition: Section Ill.G of Appendix R sets forth the requirement for fire protection for safe shutdown capability on the basis of fire areas.
A fire area is defined as that portion of a building or pl a is separated from other areas by boundary fire barriers (walls,-floors an any openings or penetrations protected withficals or closides having a fire resistance rating equal to that required of tlie barrier). Open stairwells and hatchways in ceilings and floors are not fire aren boundaries.
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etc. existing prior jo Appendix R, the rating required of a boundary fire
-barrieflibased on the guidancs in'AppeEdix A to BTPA,S8 9.5-1; i.e., the rating of thh barrierd boundafy must ex' deed with margin the fire loading -
in tiie area aid ndEiliot necessarily bel 3fhour rated boundary unless the fire loading! war $nts such a'boundar'y. For modifications which involve
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i thdinstallation df'nedboddary fire barriers pursuant to Section III.G.2.a,
. thifire rating ofiuch 'tEundaries must be three hours,' or an exemption m'ust bejdstifid[and requested.
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,The evaluations by some licensees made prior to Appendix R were based on fire zones which do not meet the strict definition of fire areas clarified above._ In some cases, the separation of redundant trains under consideration within the " fire zone boundaries" and the separation between fire zones does not comply with the separation, i.e., barrier or distance, i
requirements of Appendid R. Such configurations need to be evaluated under the exemption process.
The fire protection requirements are intended to provide reasonable assurance that at least one safe shutdown division is free of fire damage after a postulated fire in any fire area. The definition of" fire areas," noted above, is predicated on sound fire protection engineering principles as they apply to limiting the fire and fire suppressant damage to redundant shutdown equipment and cables. Fire areas defined by non-physical boundaries, such as " logical divisions or equipment groupings," may not l
necessarily restrict fire and smoke spread, and do not necessarily provide i
Rev.G 6/24/98 3-10
~
DRAFT BWROG g
(.
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.3 FIRE PROTECTION OF SAFE SHUTDOWN CAPABILITY A.
Regulations 10 CFR 50. Appendix R. Section 1. Introduction andScope. Fire Damage Limitsfor ColdShutdown di
.s "Both trains of equipment necessary to achieve cold shutdown may be damaged by a single fire, including an exposur'e fire, but damage must be limited so that at least one train can,be repaired or made ' operable within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months using onsite capability.".h F
f f
); /
k fh hN 10 CFR 50, Appendix RlSection IILG, Fire Protection ^ofSafe Shutdown 1
-Capabilitvg
% y
y
[
s ys a./
f l-d Fire prbtectI5 features shall be pa) hided for structures, sy y
l['
"1.[A components important to safe shutdown. These features shall be capable
./: ofliniiting' fire dsmase~so that:
1 i
t V
j:.
~~a..[One hain of systems necessary to achieve and maintain hot jf shutdown conditions from either the control room or~~
{
,, A emergency control station (s) be free of fire damage; and b.
Systems necessary to achieve and maintain cold shutdown from either the control room or emergency control station (s) l can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .
r 2.
Except as provided for in paragraph G.3 of this section, where cables or equipment, including associated non-safety circuits that could prevent operation or cause maloperation due to hot shons, open circuits, or shons to ground, of redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located within
'the same fire area outside of primary containment, one of the
. following means of ensuring that one of the redundant trains is free of fLe damage shall be provided:
Separation of cables and equipment and associated non-safety a.
{
circuits of redundant trains by a fire barrier having a 3-hour
. Rev. G 6/24/98 3-13 I.
\\.
}
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment rating. Structural steel forming a part of or supporting such fire barriers shall be protected to provide fire resistance equivalent to that required of the banier; b.
Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustible or fire hazards.
In addition, fire detectors and an automatic fire suppression system shall be installed in thefire area; or c f
/
f Enclosure of cable and, equipment and associated non-safety c.
circuits of one redundant train in a fire barrier having a 1-hour rating,qln ' ddition, fire l detectors atld an authmatic fire a
,, suppression system shall be iristalled in the' fir.e area; jf
< ;r%Insidep f
j' p
noninerted conta'mments one of the fire protection f'
hieand s'p'ecified above'or one of the following fire protection f:
meankshd11 be provided:'
)
f:
N f &P I
f
~~d. /. Separation of cables and equipment and associated non-safety p.~~
/ circuits of redundant trains by a horizontal distance of more fj than 20 feet with no intervening combustibles or fire hazards; p-e.
Installation of fire detectors and an automatic fire suppression system in the fire area; or f.
Separation of cables and equipment and associated non-safety circuits of redundant trains by a noncombustible radiant energy shield.
3.
Altemative or dedicated shutdown capability and its associated circuits, independent of cables, systems or components in the area, room or zone under consideration, shall be provided:
I Where the protection of systems whose function is required for i
a.
hot shutdown does not satisfy the requirement of paragraph G.2 l
I of this section; or J'
Rev. G 6/24/98 3-14
DRAFT BWROG
('
Shutdown Circuit Analysis Assessment Generic Gmdance for Post-Fire Safe b.
Where redundant trains of systems required for hot shutdown located in the same fire area may be subject to damage from fire suppression activities or from the rupture or inadvertent operation of fire suppression systems.
In addition, fire detection and a fixed fire suppression system shall be installed in the area, room, or zone under consideration."
' f l_
r 10 CFR 50, Appendix R, Section Ill.L Alternative and Eedicated Shutdown Capability e
(
y ly, l'
"1.
Altemativepr de'dicated shutdown capability provided for a specific fire 2rea shall be able to (a) a'chieve!and maintain'suberitical
~
- :.:teactivity cohditions in the reactor;l(b) maintainTdictor coolant finventory; (f). achieve and maintain hot standby' conditions for a J PWR (hot shut'down' fp'r a BWR)f(d) achieve cold shutdown
(
l conditionshithin 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ; and (e) maintain cold shutdown l:~ coolant syElthere'after.S
! conditions During the postfire shutdown, the reactor iem pYocess variables shall be maintained within those li predictedfor a loss of normal a. c. power, and the fission product h,,b6undary integrity shall not be affected; i.e., there shall be no fbel
,Vclad damage, rupture of any primary coolant boundary, of rupture of the containment boundary.
2.
The perfonnance goals for the shutdown functions shall be:
a.
The reactivity control function shall be capable of achiesing and maintaining cold shutdown reactivity conditions.
b.
The reactor coolant makeup function shall be capable of l
maintaining the reactor coolant level above the top of the core for BWRs and be within the level indication in the pressurizer for PWRs.
' As defined in the Standard Technical Specifications.
l Rev.G 6/24/98 3-15
l DRAFT BWROG
.I Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment c.
The reactor heat removal function shall be capable of achieving and maintaining decay heat removal.
d.
The process monitoring function shall be capable of providing direct readings of the process variables necessary to perform and control the above functions.
j g:
)
The supporting functions shall be capable bf providing the e.
process cooling, lubrication, etc;, necessary to' permit the operation of the equipment used for safe shutdown functions, b
X j
C 3.
The shutdown capability for specific fire Areas may be unique for each such area, ohit may be'Ene unijue combination of systems for all such areas! In either case lthe altemative shutdown capability Mhall be inde' pendent of the specific fire area (s)a'n[shall
~
yaccoritmodatepostfire con'ditions nhere offsite power is available I and where dffsite power is n'ot ay.a$lable for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Procedures p
hp
%P
-.)
l shall be inpffectto implemeniihis capability.
4./ ' If the capability to achieve and maintain cold shutdown will not be I availableMause of fire damage, the equipment and systems f
comprising the means to achieve and maintain the hot standby or hot f
' shutdown condition shall be capable of maintaining such conditions until cold shutdown can be achieved. If such equipment and systems will not be capable of being powered by both onsite and offsite electric power systems because of fire damage, an independent onsite power system shall be provided. The number of operating shift personnel, exclusive of fire brigade members, required to operate such equipment and systems shall be on site at all times.
5.
Equipment and systems comprising the means to achieve and maintain cold shutdown conditions shall not '>e damaged by fire; or the fire damage to such equipment and systems shall be limited so that the systems can be made operable and cold shutdown can be achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Materials for such repairs shall be readily available on site and procedures shall be effect to implement such repairs. If such equipment and systems used prior to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after the fire will not be capable of being powered by both onsite and offsite electric power systems because of fire damage, an
]
Rev.G 6/24/98 3-16
DRAFT BWROG
(
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment independent onsite power system shall be provided. Equipment and systems used after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered by offsite power only."
6.
Shutdown systems installed to ensure postfire shutdown capability need not be designed to meet seismic Category I criteria, single failure criteria, or other design basis accident criteria, except where required for other reasons, e.g., because ofinterface with or impact en existing safety systems, or because of adverse valve actions due to fire damage.
e' l
/
?
7.
The safe shutdown equipmentand systems for each fire area shall be known to be isolated from as'sociated non-safety circuits in the fire area so thattot shorts, openlircuitsi or shorts to p,round in the
- deqilipment. The separation,t'phvent operation of the safe sh associated circuits will no and barriers between trays and conduits I containing associated circuits of one safe shutdown division and i trays and condu'lts containinEasso'ciated circuits or safe shutdown
{'
[ associated [circu ts frorn the safe shutdown equipment, shall be such i cabled from the redundant didion, or the isolation of these l
^
p that,a postulated' fire involving associated circuits will not prevent p safe shutdoh."'
/V I
B.
Guidance NUREG-0800, SRP, Section 9.5.1, Section C.S.b, Safe Shutdown Capabilitv (1) Fire protection features should be provided for structures, systems, and components important to safe shutdown. These features should be capable oflimiting fire damage so that:
' An acceptable method complying with this altemative would be to meet Regulatory Guide 1,75 position 4 related to associated circuits and IEEE Std 384-194 (Section 4.5) where trays from redundant safety divisions are so protected that postulated fires affect trays from only one safety division.
l Rev. G 6u4/98 3-17 i
I
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment (a)
One train of systems necessary to achieve and maintain hot shutdown conditions from either the control room or emergency control station (s) is free of fire damage; and (b) Systems necessary to achieve and maintain cold shutdown from either the control room or emergency control station (s) can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .
}
3
.t
[
-j (2) To meet the guidelines of Position C5.b'.1, one of the following means of ensuring that one of the redundant trains is free of fire damage should be provided: /n f;
r.
ll
,d f
(a)
Separati$n of cables anil equipmen$and associated circuits of E
_ redundint trains by a'fiEe barrier having a 3 hour3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months rating.
<[ N.Structtital steel forminj a par,iof or supporting such fire barriers sh'ould beprotected to provide fire resistance r
k 5quivil' erit to that/ reg}ulfed pf th'e barrier; f (b) jSeparation()f.c bles and equipment and associ
)
b$
is[
fledundant Eains by a horizontal distance of more than 20 feet c with no intervening combustible or fire hazards. In addition, j fire detectors and an automatic fire suppression system should be installed in the fire area; or (c)
Enclosure of cable and equipment and associated circuits of one redundant train in a fire barrier having a 1-hour rating. In addition, fire detectors and an automatic fire suppression system should'be installed in the fire area.
(3) If the guidelines of Positions C5.b.1 and C5.b.2 cannot be met, then alternative or dedicated shutdown capability and its associated circu#.r, independent of cables, systems or components in the area, room, or zone under consideration should be provided."
l l
Rev. G 6/24/98 3-18
1 I
DRAFT BWROG i
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment NUREG-0800. SRP, Section 9.51. Section C.5.c. Mternative or Dedicated Shutdown Capabilitv (1) Altemative or dedicated shutdown capability provided for a specific fire area should be able to achieve and maintain suberitical reactivity conditions in the reactor, maintain reactor coolant inventory, achieve and maintain hot standby
~~conditions for a PWR (hot shutdown~~
~~for a BWR) and achieve cold shutdown~~
~~conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months and maintain cold shutdown~~
conditions thereafter.During the postfire shutdown, the reactor coolant system process variables shall be maintained within those predicted for a loss of norinal ac power, and the fission product boundarylintegriti shall not be'affected; i.e., there shall be no fu'el~ clad damage (rupturh;~or any primary coolant boundary, og" rupture of thf contaimhent boundary.,
af ~Y; kf fj f
f i
(2) p.The perfomiance goals for the shutdown functions should be:
(-
lf IN Q.i
[
$ /'
c he dacti$ity controlfmiction should be capable of achieving If< (a) Md draintiining cold shutdown reactivity conditions L
W g
e O (b) ' The] reactor coolant makeup function should be capable of w
y
,lg/
maintaining the reactor coolant level above the top of the core A
for BWRs and be within the level indication in the pressurizer for PWRs.
(c) The reactor heat removal function should be capable of achieving and maintaining decay heat removal.
(d) The process monitoring function should be capable of providing direct readings of the process variables necessary to perform and control the above functions.
(e) The supporting functions should be capable ofproviding the process cooling, lubrication, etc., necessary to permit the operation of the equipment used for safe shutdown functions.
I
~~As defined in the Standard Technical Specifications.~~
C
' Rev. G 6/24/98 3-19
a DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment
(
(3) The shutdown capability for specific fire areas may be unique for each such area, or it may be one unique combination of systems for all such areas. In either case, the alternative shutdown capability shall be independent of the specific fire area (s) and shall accommodate postfire conditions where offsite power is available and where offsite power is not available for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Procedures shall be in effect to implemen* this capability. g3 7 j -
sf V' Y (4) If the capability to achieve and maiatain' cold shutdown will not be available because of fire damage. the equipment an'd systems comprising die means to achieve and maintain the hot standby or hot shutdown condition shall be:6apable'ofmaintaining such conditions until cold shuidoWn can beMbieved/If duch equipment and systems will not be cgable of being powere'd by both onsite and offsite
.g electric power systems becadse of fire damage, an independent
[ onsitel power system shall be provided. The number of operating l' shift personhelTexclusive ofifire,b'igade members, required to r
. operate'such eg'uipment and'syltems shall be onsite at all times.
)
j ff h,,M
(5)' Equip [mentand s stems comprising the means to ach C maiittaini:51d shutdown conditions should not be damaged by fire;.
? jthe fire damage to such equipment and systems should be limited so that the systems can be made operable and cold shutdown achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Materials for such repairs shall be readily available onsite and procedures shall be in effect to implement such repairs. If such equipment and systems used prior to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after the fire will not be capable of being powered by both onsite and offsite electric power systems because of fire damage, an independent onsite power system should be provided. Equipment and systems used after 72 hour:: may be powered by offsite power only.
(6) Shutdown systems installed to ensure postfire shutdown capability need not be designed to meet seismic Category I criteria, single failure criteria, or other design basis accident criteria, except where required for other reasons, e.g., because ofinterface with or impact on existing safety systems, or because of adverse valve actions due to fire damage.
)
J!
Rev.G 6/24/98 3-20
DRAFT BWROG
('
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment (7) The safe shutdown equipment and systems for each fire area should be known to be isolated from associated circuits in the fire area so that hot shorts, open circuits, or shorts to ground in the associated
^
circuits will not prevent operation of the safe shutdown equipment.
The separation and barriers between trays and conduits containing associated circuits of one safe shutdown division and trays and conduits containing associated circuits or safe shutdown cables from the redundant division, or the isolation of these asso'ciated circuits from the safe shutdown equipment, shoiild bh such.that a postulated fire involving associated circuits will not preve. t safe shutdown.
t?
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p GenericLetter813$(firstparethcover!!e$t )
h Vk
/M ll hs n
s..,wh'efEcables or equipment / including associated non-safety circuits, thatfcould prevenfoperation or Eause maloperation due to hot shorts, open circhits or shortsito ground or (sicIredundant trains of systems necessarj
(.-
same fire aka otYtside'of, primary containment..."*
to achieve and n1Iaintiin hot shutdown conditions are located within the i
ir p
p y
,1 ew
~~l" Quoted from~Section Ill.G.2 of Appendix R to 10 CFR Part 50. Note that theor" preceding " redundant trains" is a typographical error and jho#0ld read "of redundant trains".~~
Gen'eric Letter 81-12, Enclosure i, Sta8 Position, Safe Shutdown Capability. Section 2.3 "The alternative shutdown capability shall be able to achieve and maintata l
suberitical conditions in the rector (sic), maintain reactor coolant L
inventory, achieve and maintain hot standby
~~conditions (hot shutdown~~
~~for a BWR) for an extended period of time, achieve cold shutdown~~
~~conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months and maintain cold shutdown conditions thereafter."~~
~~As defined in the Standard Technical Specifications.~~
Rev. G 6/24/98 '
3-21 i
L
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Ass-ssment Generic Letter 81-12. Enclosure 1. StaffPosition. Safe Shutdown Capability, Section 3.6 The equipment and systems used to achieve and maintain hot standby conditions (hot shutdown for a BWR) should be (1) free of fire damage..."
pa Generic Letter 81-12. Enclosure 1. Sta8 Position, Safe Shutdow, n Capability, Section 3.7
,3
't j 9
p "The equipment and systems used to achieve and maintain cold shutdown conditions should be either free of fire damagel>r the fire damage to such systems should be linifted such that repairs c~aii'be madhand cold shutdown conditions achieved viithin 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .' Equipment and systems
'poyered bylan onsit,e emergenhy'jx(sic) slkuld be ca usedpri6Fto 72 hfurs a'fter the fir
)wer /rkstem; those used after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered,by ffsite p,ower{ ji-y k5w
/ r
)
li RE Rf Generic Lhter 81-12. Enclosure 2, Requestfor AdditionalInformation.
Request No. If r
e lhv*betion III. O of Appendix R to 10 CFR Part 50 requires cabling for d
or associated with redundant safe shutdown systems necessary to
' achieve and maintain hot shutdown conditions be separated by fire barriers having a three-hour fire rating or equivalent protection (see Section III.G.2 of Appendix R). Therefore, if option III.G.3 is
. chosen for the protection of shutdown capability cabling required for or associated with the alternative method of hot shutdown for each fire area, must be physically separated by the equivalent of a three-hour rated fire barrier from the fire area.
In evaluating alternative shutdown methods, associated circuits are circuits that could prevent operation or cause maloperation of the alternative train which is used to achieve and maintain hot shutdown condition due to fire induced hot shorts, open circuits or shorts to ground..."
. Rev. G 6/24/98 3-22
DRAFT BWROG
~
t
,(
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment Generic Letter 86-10, Enclosure 1. Interpretations ofAppendix R. Repair ofColdShutdown Equipment. Also Generic Letter 85-01, Enclosure 3.
l Interpretations ofAppendix R. Repair ofCold Shutdown Equipment l
"Section Ill.L.5 of Appendix R states that when in the altemative or l
dedicated shutdown mode, ' equipment and systems comprising the means l
to achieve and maintain cold shutdown conditions shall not be damaged l
by fire; or the fire damage to such equipment and sys'tems shall be limited i
so that the systems can be made operable and cold. shutdown can be F
l achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .'
i f
l*
Section III.G.I.b contains the requirements for} normal shutdow t
utilizing the contr61Ir3om or emergency chnEol station (s) capabilities.
The fire areas falling udder the r' quireme'nts ofIII.G. lib are those for e
which'aii' alternative of dedicat'ed shutdown capability iinot being l
provided. For these. fire areas,'Section Ill.G.I.b requires only the capaliility tolTepair%e systedis ne'cessar'yIo achieve and maintain cold
('
shutdown from ciither the controj room or emergency control station (s) within 72 Iferrs[not the cahability to repair and achieve cold shutdown within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months 'as reghired for the alternative or dedicated shutdown m' odes b 'SectiEdIII.L (noted above).
f
,Witli regard to areas involving normal shutdown, however,Section I of Appendix R states that repairs must be made using only onsite capabilities.
After repairs are made, cold shutdown can be achieved on a reasonable schedule using any available power source."
SECY83-26o, dtru.:.%ent C, NRC StaWPositions on Post Fire Shutdown Capability, Allowable Time to Achieve Safe Shutdo q Some diffh ulty was being experienced on the part of the staff and licensees co.scerning the time allowed to achieve cold shutdown and whether credit for offsite power could be used in designing the cold shutdown c spability. To establish consistency in all plant designs, the staff issued the following position (reference: memorandum from R. Mattson to R. Vollmer, dated July 2,1982).
Rev.G 6/24/98 3-23
DRAFT BWROG Generic Guidance for Post Fire Safe
)
Shutdown Circuit Analysis Assessment
- Section III.G to Appendix R states that fire damage to cold shutdown capability must be limited to damage that can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .
Section III.L.1 of Appendix R states that the alternative shutdown capability shall be able to achieve cold shutdown within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .
Further,Section III.L~ 5 of Appendix R states that fire damage shall be limited so that the systems can be made operable and cold shutdown achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Sections III.L.1 and III L.5, statis that a plant must be capable of achieving cold shutdown using only onsitepower prior to the elapse of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months .Section III.L.5 also clearly
states that offsite power is assumed restored after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months in ihat eciuipment and systems not needed until 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered ~by offsite poker only.
8
.b,d h
g We have been usdand proposeifcontidue t(use Sec'tions III.L.1 and III.L.5 itur evahiations. Thust'a licensee should haveIthe capability of mepairisii'equipmeInt and'achievind cold shutdown within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months using
~
~
only onsite powed.Tiie 72 hoids is considered an upper limit; a licensee ma limit tlki re "r's and achieve I:oldguidown in a shorter time frame.
.)
If p
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a SECY 83-269, A ttach5ent C, NRC StaffPositions on Post Fire Shutdown Capability, Allowable Repairs to Achieve Safe Shutdown p~ p
,Sedt on III.G of Appendix R states that repairs are permitted to provide the cold shutdown capability. Additionally,Section III.L indicates that procedures for these repairs must be developed and materials needed for the repairs stored on site. To establish consistency in the plant designs, the staffissued the following guidelines concerning repairs. (memorandum R.
Mattson to R. Vollmer, dated July 2,1982)
Section III.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage. Thus, one train of systems needed for safe shutdown has to be operable during and following the fire.
Operability of the hot shutdown systems, including the ability to overcome a fire or fire suppressant induced maloperation of hot shutdown equipment and the plant's power distribution system, must exist without repairs.
Manual operation of valves, switches and circuit breakers is allowed to operate equipment and isolate systems and is not considered a repair.
However, the removal of fuses for isolation is not permitted. All manual Rev.G 6/24/98 3-24
l I
DRAFT BWROG l (~
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment l
operations must be achievable prior to the fire or fire suppressant induced maloperations reaching an unrecoverable plant condition.
Modifications, e.g., wiring changes, are allowed to systems and/or components not used for hot shutdown, whose fire or fire suppressant induced maloperations may indirectly affect hot shutdown. These repairs must be achievable prior to the maloperations causing an unrecoverable plant condition.
f,l
!)
Af i
W.
g e_
Repairs for cold shutdown systems are allo'wed by Section Ill.L.5 of Appendix R. For cold shutdown capability repairs, the removal of fuses for isolation and the replacement ofcablin),isprmitted. Also, selected equipment replacedient, e.g., such,ih replicing)a valve,fpump, control room controls and$nstr6ments, Aill be reiiewed on a case-by case basis to
-merify'itspracticasty within the' appropriate time constraints. Procedures for repairing damaged equipment should be prepared in advance with repla* cement equipment (i.e.,/ cables made4ip with terminal lugs attached)
(
stored onsite.~ All repairs sh' uld.be~ 'of sufficient quality to assure safe o
operation u'ntil tile plant.isNstored to an operating condition. Repairs not pennitted include,the 6se of clip leads in control panels (which means the hard wired' terniin' al lugs must be used), and the use ofjumper cables other than those fastened with terminal lugs.
vr 7
When repairs are necessary in the fire area, the licensee should demonstrate that sufficient time is available to allow the area to be reentered and the expected fire and fire suppressant damage will not prevent the repair from taking place and that repair procedure will not endanger operating systenis. In addition, written procedures must exist for the orderly transfer of control from the control room and the remote shutdown stations and vice versa. The repairs to cold shutdown systems are considered to be an upper limit. The licensee may design the plant so that cold shutdown can be achieved without repair.
Rev.G 6/24/98 3-25
l 1
l l
l DRAFT BWROG Generic Guidance for Post Fire Safe
)
Shutdown Circuit Analysis Assessment Mattson to Vollmer InternalNRC Memo of 7/2/82. Position Statement on Allowable Repairs on the Appendix R Requirementfor Time Required to Achieve ColdShutdown "Section Ill.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage. Thus, one train of systems needed for hot shutdown must be operable during andfollowidg a fire.
Operability of the hot shutdown systems, including the ability to overcome a fire or fire suppressant induced maloperatio' of hot shutdown equipment s
and the plant's power distribution system, tnust exist without repairs.
Manual operation of valves, switches and circuit breakers.is allowed to operate equipment and isolate systems and is obt considered a repair.
However, the remivil of fuses forisolation'is bot permitted. All manual operations must bE achievable prio*r to thhfire or fire s6ppressant induced malophrations reaching an unrecoverable plant condition."
c g.-
ll C
jd r'~ V b
" Modifications, e.g.,\\ wiring change, age'alfowed to systems and/or components'not usedior hot shutdown, but whose fire or fire suppressant
)
induced maloperation'stnajiindirectly affect hot shutdown. These repairs m,ust be achievabl,e prior to the maloperations causing an unrecoverable plant condition.**
fV r
)!the' removal of fuses for isolation and the replacement of cabling is permitted. Also, selected equipment replacement, e.g., such as replacing a valve, pump, control room controls and instruments, will be reviewed on a case-by-case basis to verify its practicality within the appropriate time constraints. Procedures for repairing damaged equipment should be prepared in advance with replacement equipment (i. e, cables made up with terminal lugs attached) stored onsite. All repairs should be of sufficient quality to assure safe operation until the plant is restored to an operating condition. Repairs not permitted included the use of clip leads in control panels (which means that hard wired terminal lugs must be used),
and the use ofjumpers other than those fastened with terminal lugs."
"When repairs are necessary in the fire area, the licensee will have to demonstrate that sufficient time is available to allow the area to be re-entered and that expected fire and fire suppressant damage will not prevent the repair from taking place and that repair procedure will not endanger operating systems. In addition, written procedures must exist for the
]
Rev. G 6/24/98 3-26
DRAFT BWROG
(
Generic Guidance for Post-Fire Safe i
Shutdown Circuit Analysis Assessment orderly transfer of control from the control room and the remote shutdown stations and vice versa. The repairs to cold shutdown systems are considered to be an upper limit. The licensee may design the plant so that cold shutdown can be achieved without repair."
C.
Conflic ting Guidance
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DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment
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DRAFT BWROG
~
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Generic Guidar-lor Post-Fire Safe Shutdown Circua Anysis Assessment i
3.1.4 HOT SHUTDOWN / COLD SHUTDOWN DEFINITIONS A.
Regulations JO CFR 50, Appendix R. Section 1HL. Alternative and Dedicated Shutdown Capability 4
"1.
Alternative or dedicated shutdown capability provid'ed for a specific fire area shall be able to (a) achieve and ' maintain suberitical i
reactivity conditions in the reactor; (b) maintain reactor coolant inventory; (c) achieve and maintain hot standby' conditions for a 5
PWR (hot shutdown for a BWR);(d) achieve cold shutdown conditions within\\72 hours;I 'nd (e)l a
inaintain cold'simtdown conditions tliereafter..." / f i
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.r NUREG-0800, $RP. Sectidn 9.5.1, Section C.5.c Alternative or Dedicated Shutdown. Capability v f-
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d' Alternative or dedicated shutdown capability provided for a specific
[(1)fire area should be able to achieve and maintain subcritical reactivity conditions in the reactor, maintair, reactor coolant inventory, achieve and maintain hot standby
~~conditions for a PWR (hot shutdown~~
~~for a BWR) and achieve cold shutdown~~
~~conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months and maintain cold shutdown~~
~~conditions thereafter..."~~
1 l
l-8 As defined in the Standard Technical Specifications.
~~As defined in the Standard Technical Specifications.~~
Rev.G 6/24/98 3-29 i
DRAFT BWROG Generic Guidance for Post-Fire Safe
}
Shutdown Circuit Analysis Assessment Generic Letter 81-12. Enclosure 1. StaffPosition. Safe Shutdown Capability. Section 6 "BWR Equipment Generally Necessary For Hot Shutdown (1) Reactivity Control gg
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Reactor trip capability (scram).
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(2) Reactor Coolant Makeup Reactor coolantinventory makeup capabiIity e.g.,l(reac
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isolation cooling system (RCIC) or the high pressure coolant injection sysiem (HPCI). / [
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(3),f Reactor Pressure Control'and Decay Heat Removal p
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[ the sdppreIsion'poolSThe residual heat removal system in steam r' condensing mods, and service water system may also be used for
&[i heafremo' val to the ultimate heat sink.
d
,(k)*, suppression Pool Cooling Residual heat removal system (in suppression pool cooling mode) service water system to maintain hot shutdown.
(5) Process Monitoring' Process monitoring capability e.g., reactor vessel level and pressure and suppression pool temperature.
(6) Support Support capability e.g., power sources (AC and DC) and their associated distribution systems to provide for the shutdown equipment. Onsite power sources are required for alternative shutdown equipment.
J Rev.G 6/24/98 3-30
DRAFT BWROG
(~-
' Generic Guidance for Post-Fire Safe
. Shutdown Circuit Analysis Assessment BWR Equipment Ge..erally Necessary For Cold Shutdown
~~At this point the equipment necessary for hot shutdown has reduced the primary system pressure and temperature to where the RHR system may be placed in service in RHR cooling mode.~~
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(1) Decay Heat Removal
_A 4hV Residual heat removal system in the.RHR cooling mode, service water system.
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(2) Support b1
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- fssociated distribution systems to provide for the shutdown y& DC) or cfsiy.after '/2 hours and their associated dis T
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f systems are required to providi power for shutdown equipment."
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~~jEquipment pmvided'in addition to that for achieving hot shutdown.~~
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, Gen' ric Letter 86-10 Enclosure 2, Appendix R Ouestions andAnswers, e
Section 3.4.4, FixedSuppression System in Fire Area.- Also Generic Letter 85-01. Enclosure 6, Appendix R Questions andAnswers, Section 3.4.4, FixedSuppression System in Fire Area QUESTION Are fixed suppression systems required by Section III G.3 to be throughout the fire area, room or zone under consideration?
~~RESPONSE~~
No, but partial coverage must be properlyjustified and documented. See Item #5 of the "Integretations of Appendix R."
" suppression less than full area coverage may be adequate to comply with the regulation. Where full area suppression and detection is not installed, licensees must perform an evaluation to assess the adequacy Rev.G 6/24/98 3-31
DRAFT BWROG -
Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment and necessity of partial suppression and detection in an area. The evaluation must be performed by a fire protection engineer and,if required, a systems engineer. Although not required, licensees may submit their evaluations to the staff for review and concurrence. In any event, the evaluations must be retained for subsequent NRC audits..."
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. p -l rc Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers, Section 5.3.4, Cooldown Equipment. Also Generic Ixtrer 85-01,. Appendix R Questions and Answers, Section 5.3.4. Cooldown Equipment f
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-Certain' equipment is necessary'only in the cooldown phase when the plant is n'either iiihot n'occold shutdown condition as defined by technical specifications. Issh'is'equipm'ent cEnsidedd hot or cold shutdown in
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RESPONSE /
f/f As statid in Section III.G.1, one train of systems needed to achieve and Msintain hot shutdown conditions must be free of fire damage. Systems necessary to achieve and maintain cold shutdown can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Thus, if this certain equipment necessary only in the cooldown phase, is used to achieve cold shutdown, it can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . If the certain equipment is maintaining hot shutdown while repairs are being made, one train ~ must be free of fire damage. See also Section
~~2 of the " Interpretations of Appendix R."~~
C.
Conflicting Guidance Rev.G 6/24/98 3-32 i
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DRAFT BWROG l(.
Generic Guidance for Post Fire Safe l
Shutdown Circuit Analysis Assessment 3.1.5 REDUNDANT, ALTERNATIVE (ALTERNATE) OR DEDICATED SHUTDOWN CAPABILITY A.
. Regulations l
10 CFR 50. Appendix R, Section HD Alternative or DedicatedShutdown Capability
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ga, "In areas where the fire protection features ca'nnot ensure safe shutdown capability in the event of a fire in that area (alternative or^ dedicated ufe shutdown capability shall be provided." p/
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10 CFR 50, Appendix R,;Section IRG Fire Protection ofSafe Shutdown
-Capabilitv.).
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h "3.[Altema'tive o'Gf rMdicatedplhutdownlipability and its associated
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circuits, inElepeislen't'of cables,iysiems or components in the area, room 2
or Mone under cdasideratioEhhall be provided:
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protection of systems whose function is required for hot a.y jutdown does not satisfy the requirement of paragraph G.2 of this F section; or b.
Where redundant trains of systems required for hot shutdown located in the same fire area may be subject to damage from fire suppression activities or from the rupture orinadvertent operation offire suppression systems'.
In addition, fire detection and a fixed fire suppression system shall be installed in the area, room, or zone under consideration."
j I
Altemative shutdown capability is provided by routing, relocating or modificating (sic)
)
2 of existing systems; dedicated shutdown capability is provided by installing new I
structures and systems for the function of post-fire shutdown.
Rev.G 6/24/98 3-33
DRAFT BWROG Generic Guidance for Post-Fire Safe
,)
Shutdown Circuit Analysis Assessment 10 CFR 50. Appendix R, Section 111.L Alternative and Dedicated Shutdown Capability i
"1.
Alternative or dedicated shutdown capability provided for a specific l
fire area shall be able to (a) achieve and maintain suberitical i
reactivity conditions in the reactor; (b) maintain reactor coolant inventory; (c) achieve and maintain hot standby' condit}' ohs for a PWR (hot shutdown' for a BWR); (d) achieve cold shutdown conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ; and (e) maihtain cold shutdown conditions thereafter. During.the postfire shutdowi the reactor coolant system process variables shall be, maintained within those predicted for a loss of normal a. c. power; and the. fission product boundary integ'rityshall not'b' affected; he., there shall be no fuel e
clad damage lruptiire of an'y primary. coolant bound,ary, of rupture of
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~~2. hlThe perform &f l~~
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D Sh ance goals!for the situtdown functions shall be:
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J pe reactihtycontrol function shall be capable of achieving h a.
chnd inaintalhing cold shutdown reactivity conditions.
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The reactor coolant makeup function shall be capable of
/>7 maintaining the reactor coolant level above the top of the core for BWRs and be within the level indication in the pressurizer for PWRs.
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The reactor heat removal function shall be capable of achieving and maintaining decay heat removal.
d.
The process monitoring function shall be capable of providing direct readings of the process variab:es necessary to perform and control the above functions.
e.
The supporting functions shall be capable of providing the process cooling, lubrication, etc., necessary to permit the operation of the equipment used for safe shutdown functions.
8 As defined in the Standard Technical Specifications.
s.
. Rev. G 6/24/98 3-34
DRAFT BWROG
['
Generic Guidance for Post Fire Safe Shutdown Circuit Analysis Assessment L
i 3.
The shutdown capability for specific fire areas may be unique for.
I each such area, or it may be one unique combination of systems for all such areas. In either case, the alternative shutdown capability shall be independent of the specific fire area (s) and shall l
accommodate postfire conditions where offsite power is available and where offsite power is not available for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Procedures
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shall be in effect to implement this capability.
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4.
If the capability to achieve and maintain' cold shutdown will not be available because of fire damage, the' equipment and systems comprising the means to achieve and maintain the hot standby or hot shutdown condition shall be hapablefof.m'aintaining such conditions until cold shtitd6wn can be Schieved' If such equipment and systems l
willnot be chable of beirig powered by both onsite, and offsite
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,g? onsit(power system shall be provided. The number o elictric power systems because of fire damage, an' independent kshift ;ierson' nil { exclusive of-fire,bNiade members, required to l{
l 6o b perate such eq~uipment and sy' stems shall be on site at all time y
p gy 5.fi Equjpment and systems comprising the means to achieve and I
mamtaintold shutdown conditions shall not be damaged by fire; or b/c fire damage to such equipment and systems shall be limited so
/
that the systems can be made operable and cold shutdown can be.
achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Materials for such repairs shall be readily available on site'and procedures shall be effect to implement such repairs. If such equipment and systems used prior to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after the fire will not be capable of being powered by both onsite and offsite electric power' systems because of fire damage, an independent onsite power system shall be provided. Equipment and systems used after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered by offsite power only."
6.
Shutdown systems installed to ensure postfire shutdown capability I
need not be designed to meet seismic Category I criteria, single l
failure criteria, or other design basis accident criuria, except where required for other reasons, e.g., because ofinterface with or impact L
on existing safety systems, or because of adverse valve actions due I
to fire damage.
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Rev. G 6/24/98 -
3-35 g
t i
-DRAFT BWROG Generic Guidance for Post Fire Safe
}
Shutdown Circuit Analysis Assessment 7.
The safe shutdown equipment and systems for each fire area shall be known to be isolated from associated non-safety circuits in the fire area so that hot shorts, open circuits, or shorts to ground in the associated circuits will not prevent operation of the safe shutdown equipment. The separation and barriers between trays and conduits containing associated circuits of one safe shutdown division and trays and conduits containing associated circuits.or:siffihutdown cables from the redundant division, or the isolati6n of thdse associated circuits from the safe shutdown equipme'nt, shall be such that a postulated fire involving assochted circuits will not prevent safe shutdown.'"
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n NUREG-0800, SRP<Section 9.5.lfSection C.J.d, Alternative or Dedicated Shutilown Capabilityk
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Alternative &
[slicated.sh'utdown capability should be provided where f
or de th$ protection ofyysteIi5 whose functions are required for safe shutdown isSiot provided by established fire suppression methods or by Position
.<fBWROG Note: C.5.6 is a typo, should be C.5.c.)
- NUREG-0800, SRP, Section 9.5.1, Section C.S.c, Alternative or Dedicated Shutdown Capability
"(1) Altemative or dedichted shutdown capability provided for a specific fire area should be able to achieve and maintain suberitical reactivity conditions in the reactor, maintain reactor coolant inventory, achieve d An acceptable method complying with this altemative would be to meet Regulatory Guide 1.75 position 4 related to associated circuits and IEEE Std 384-194 (Section 4.5) where trays from redundant safety divisions are so protected that postulated fires affect trays from only one safety division.
Rev.G 6/24/98 3-36
- DRAFT BWROG
('
Generic Guidance for Post Fire Safe Shutdown Circuit Analysis Assessment l
and maintain hot standby
~~conditions for a PWR (hot shutdown~~
~~for a BWR) and achieve cold shutdown~~
~~conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months and L~~
maintain cold shutdown conditions thereafter. During the postfire L
shutdown, the reactor coolant system process variables shall be maintained within those predicted for a loss of normal ac power, and the fission product boundary integrity shall not be affected; i.e., there -
shall be no fuel clad damage, rupture, or (sic) anyMa7y coolant l
L boundary, or rupture of the containment boun'dary. [:i'
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(2) The performance goals for the shutdo'wn functions lshould be:
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(a) The reactivity control function iihould be capable of achieving and maintaining cold sisutdowi1 reactivity conditions.
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- 4(b)iThe reactor c' oolantmakeup fiinction should'be capable of h
' maintaining the reactor coola'nt level above the top of the core for BWsk..
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. 7 e feactopheat removal function should be capable of
.i cachiEving and maintaining decay heat removal.
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P j) The process monitoring function should be capable of r"
providing direct readings of the process variables necessary to perform and control the above functions.
(e) The supporting functions should be capable of providing the process cooling, lubrication, etc., necessary to permit the operation of the equipment used for safe shutdown functions.
(3) The shutdown capability for specific fire areas may be unique for each such area, or it may be one unique combination or systems for all such areas. In either case, the alternative shutdown capability shall be independent of the specific fire area (s) and shall accommodate postfire conditions where offsite power is available and where offsite power is not available for 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Procedures H
shall be in effect to implement this capability.
~~As defined in the Standard Technical Specification.~~
Rev.G 6/24/98 3-37
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment (4) If the capability to achieve and mMntain cold shutdown will not be available because of fire damage, the equipment and systems comprising the means to achieve and maintain the hot standby or hot shutdown condition shall be capable of maintaining such conditions until cold shutdown can be achieved. If such equipment and systems will not be capable of being powered by both onsite and offsite electric power systems because of fire damage, anindependent onsite power system shall be provided. The number"of operating shift personnel, exclusive of fire brigade members,lequired to operate such equipment and systems shall be onsite at all times.
E f
i (5) Equipment and systems comprising the means to ai:hieve and maintain cold shutdown codditions sh6uid not be# amaged by fire; d
or the fire dahiageSto suchippmeit and systemEshould be limited
- gs$that the s stemi can be[made operable and coidIhutdown achieved within"72 hour8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months s:Waterials for such repairs shall be readily pf available oEs~iTeand pro'ceddes $h$11'be in effect to imple h repairkIf s'uchlequipnientMid' systems used prior to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after
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~
the fife wi[1 not be.cahable of being powered by both onsite and
) offsjic elecipe poEer systems because of fire damage, an
_ independent onsite power system should be provided. Equipment jd systems used after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered by offsite power only.
(6) Shutdown systems installed to ensure postfire shutdown capability need not be designed to meet seismic Category I criteria, single failure criteria, or other design basis accident criteria, except where required for other re~asons, e.g., because ofinterface with or impact on existing safety systems, or because of adverse valve actions due to fire damage.
(7) The safe shutdown equipment and systems for each fire area should be known to be isolated from associated circuits in the fire area so that hot shorts, open circuits, or shorts to ground in the associated circuits will not prevent operation of the safe shutdown equipment.
The separation and barriers between trays and conduits containing associated circuits of one safe shutdown division and trays and conduits containing associated circuits or safe shutdown cables from the redundant division, or the isolation of these associated circuits
]
Rev.G 6/24/98 3-38
DRAFT BWROG
.(-
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment from the safe shutdown equipment. should be such that a postulated fire involving associated circuits will not prevent safe shutdown.
NUREG-0800, SRP, Section 9.51. Section C.7.f Remote Safety-Related Panels s
..,g3 Redundant safety-related panels remote from the. cont ol om complex should be sepsrated from each other by barriers having a minimum fire rating of 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months . Panels providing remote shutdown capability should be separated from the control room coinplex py barriers having a minimum j
fire rating of 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months . Panels providing reinote' shutdown capability j
should be electrically isolated from the coInirolloom cdmplex so that a fire
]
in either. area will hot affect shuf' own capability from the other area. The d
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-generafinea housiIig remote safety-related panels sho$18 be provided with I
automatic fire detecto'rs that alarm locally and alarm and annunciate in the control rooE Ch$ustible diaterials shonld be controlled and limited to
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tho' e requir*5d for ophtion' Porta @e extinguishers and manual those s
i stations sh$did be rea'dilyivhilable in the general area.
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Generic' Letter 81-12, Enclosure 1. StafPosition, Safe Shutdown
$apability, Section 2.3 "The alternative shutdown capability shall be able to achieve and maintain subcritical conditions in the rector (sic), maintain reactor coolant inventory, achieve and maintain hot standby
~~conditions (hot shutdown~~
~~l for a BWR) for an extended period of time, achieve cold shutdown~~
~~l conditions within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months and maintain cold shutdown conditions thereafter."~~
i L
1 l
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~~As defined in the Standard Technical Specifications.~~
Rev.G 6/24/98 3-39 L_-
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment Generic Letter 81-12, Enclosure 2. Requestfor Additionalinformation.
l Request No.1 1.
Section III. G of Appendix R to 10 CFR Part 50 requires cabling for or associated with redundant safe shutdown systems necessary to achieve and maintain hot shutdown conditions be separated by fire barriers having a three-hour fire rating or equivalent piotection (see Section III.G.2 of Appendix R). Therefor.e,.if optioriIII.G.3 is chosen for the protection of shutdown ca'pabi,lity cabling required for or associated with the alternative method of hot shutdown for each fire area, must be physically separated by,the equivalent of a three-hour rated fire barrier from the fire area. (
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j In evaluating altemative shutdown metho'ds, asso[ciated cir
.o cirIni(ts that gul,d prevenioperatiod or cause rpalo[>eration of the
[k altemative tram >which is u
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4 condiEbn d$ifo fire induced hot shorts, open circuits or shorts to.
groun@
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Safe related safety related cables that are associated with
[ theSquipinEnt and cables of the alternative, or dedicated method of S sh6tdown are those that have a separation from the fire area less than
/
,#.that required by Section III.G.2 of Appendix R to 10 CFR 50 and have either (1) a common power source with the alternative shutdown equipment and the power source is not electrically protected from the post-fire shutdown circuit of concem by coordinated circuit breakers, fuses or similar devices, (2) a connection to circuits of equipment whose spurious operation will adversely affect the shutdown capability, e.g., RHR/RCS Isolation Valves, or (3) a common enclosure, e.g., raceway, panel, junction box, with alternative shutdown cables and are not electrically protected from the post-fire shutdown circuits of concern by circuit breakers, fuses or similar devices.
For each fire area where an alternative or dedicated shutdown method,in accordance with Section III.G.3 of Appendix R to 10 CFR Part 50, is provided by proposed modifications, the following information is required to demonstrate that associated circuits will Rev. G 6/24/98 3-40
DRAFT BWROG
('
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment
. not prevent operation or cause maloperation of the alternative or dedicated shutdown nethod:
A.
Provide a table that lists all equipment including instrumentation and support system equipment that are required by the alternative or dedicated method of achieving and maintaining hot shutdown.
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B.
For each alternative shutdown eqtiipment listed in 1.A above, provide a table that lists the essential cables (instrumentation, control and power) that are located in the fire area.
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Y Provide a table that lis}ts ' safety rblated and non-safety rela C.
, cables issociated with the eqjpment and cables constituting
- [_ithe alternative or dedicated method of shutdown that are F
locatedin the fire area.?.
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Showthat fire-in'duced fhilures of the cables listed in B and C k
InbovIwill:not.pnivent operation or cause maloperation of the i
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[htternative o^r dedicated shutdown method.
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For each cable listed in 1.B above, provide detailed electrical
,A schematic drawings that show how each cable is isolated from the fire area.
Generic Letter 8610, Enclosure 1, Interpretations ofAppendix R. Item 6, Alternative or Dedicated Shutdown. Also Generic Letter 85-01. Enclosure 3, Interpretations ofAppendix R. Item 6. Alternative or Dedicated Shutdown "Section III.G.3 of Appendix R provides for ' alternative or dedicated shutdown capability and its associated circuits, independent of cables, systems or components in the area, room, or zone under consideration.'
]
While ' independence' is clearly achieved where alternative shutdown equipment is outside the fire area under consideration, this is not intended to imply that altemative shutdown equipment in the same fire area but independent of the room or the zone cannot result in compliance with the regulation. The ' room' concept must bejustified by a detailed fire hazards l'
Rev.G 6/24/98 3-41 i
I L:
DRAFT BWROG Generic Guidance for Post Fire Safe
)
Shutdown Circuit Analysis' Assessment analysis that demonstrates a single fire will not disable both normal shutdown equipment and the alternative shutdown capability."
Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers.
- Section 3.1.5, Fire Zones. Also Generic Letter 85-01, Enclosure 6, Appendix R Questions and Ansuers. Section 3.1.5, Fire Zonesi i
.g!es y!f j
QUESTION E
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" Appendix R,Section III.G.3 states 'alternativepr dedichted shutdown capability and its associated circuits, inde;iendent of cables, systems or components in the arsa room or zoime under consideration...."
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"...!the NRCsecogmied tha}in so^4 IF G
a me cases where fire areas are independed,St mp noj be possible'to provide altemate
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designated of the fitgea'and,'therefore, would have to be evaluated on the basis of.firemneswiDdn the fire area. The NRC also recognized that bddause some)icensees had not yet performed a safe shutdown analysis, se yses may identify new unique configurations.
To cover the large variation of possible configurations, the requirements of Section III.G were presented in three Parts:
Section III.G.1 requires one train of hot shutdown systems be free of fire damage and damage to cold shutdown systems be limited.
Section III.G.2 provides certain separation, suppression and detection requirements within fire areas; where such requirements are met, analysis is not necessary.
Section III.G.3 requires alternative dedicated shutdown capability for configurations that do not satisfy the requirements ofIII.G.2 or where fire
! suppressants released as a result of fire fighting, rupture of the system or inadvertent operation of the system may damage redundant equipment...
Rev.G 6/24/98 3-42 a
DRAFT BWROG 4
'(
Generic Guidance for Post-Fire Safe L-Shutdown Circuit Analysis Assessment Section Ill.G recognizes that the need for alternate or dedicated shutdown capability may have to be considered on the basis of a fire area, a room or a fire zone. The alternative or dedicated capability should be independent l
of the fire area where it is possible to do so (See Supplementary Information for the final rule Section III.G). When fire areas are not designated or where it is not possible to have the alternative.or dedicated 3
capability independent of the fire area, careful considerate 6riniust be given to the selection and location of the attemative or<iedidateE shtitdown capability to assure that the performance req 6irem'ent' set'forth in Section 111.G.1 is met. Where alternate or dedicated shutdown is[provided for a room or zone, the capability must be physically.and electrically independent of that room or zone.dThe vulnerability ofthe equipment and L
personnel required'aYthe location'df the affemative or dedicated shutdown capability.to the e$vironments produced 41 that locatios as a result of the
. fire offirssuppressant'imust be chluateil. These environments may be
' due to the hot layer..sinoke, drifting suppressants, common ventilation l
syst'cIns, coldmoidrain syste'ms or flo.odisg. In addition, other
{-
int $ faction / bet en ihe locations ni'ay be possible in unique co$figurati, Mis.
7
,e r
l It'altem e shutdown is provided on the basis of rooms or zones, the kv/n of fire detection and fixed suppression is only required in the pom or zone under consideration. Compliance with Section III.G.2 cannot be based on rooms or zones.
p i.
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Generic Letter 86-10, Enclosure 2, Appendix R Questions and Answers, Section 3.8.3, Redundant Trains / Alternate Shutdown. Also Generic Letter 85-01. Enclosure 6, Appendix R Questions and Answers, Section 3.8.3, Redundant Trains / Alternate Shutdown QUESTION
" Confusion exists as to what will be classified as an alternate shutdown system and thus what systems might be required to be protected by suppression and detection under Section Ill.G.3.b. For example, while we are relying upon the turbine building condensate system for a reactor building fire and the RHR system for a turbine building' fire, would one system be considered the attemative to the other. If so, would suppression R,ev. G 6/24/98 3-43
- DRAFT BWROG Generic Guidance for Post-Fire Safe
}
Shutdown Circuit Analysis Assessment 1
and detection be required for either or both systems under III.G.3.b? An explanation of alternative shutdown needs to be advanced for all licensees."
RESPONSE' "If the system is being used to provide its design function /herally is considered redundant. If the system is being usedin l'ieuyf the preferred l
system because the redundant components.of the preferred system does not meet the separation criteria of Section III.G.2, the system is considered an attemative shutdown' capability. Thus, for the example above,it appears that the condensste syst5m is'providi5h alternative shutdown capabilityin-lieu of se;iarating redundant codiponents of the RHR System. Fird detection and dlfixed fire suppression system would be
_ -requiredin~ the arewheie sepalation of fedundant coni %nents of the a
RHlisystem is ndipdvided. ifNEever,[ safe shutdown and is n fire [ihe RHR sys"teriiwould be usb for
~
considered Im alterna'tive cafability.*~1fowever, one train of the RHR
}
syliem muit'be $eparided hem Se turbine building."
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,~ hv Gener' Letter 86-10, Enclosure 2, Appendix R Ouestions and Answers, Se& tion 5.1.1, Previously AcceptedAlternative Shutdown Capability. Also
' Generic Letter 85-01, Enclosure 6, Appendix R Questions and Answers, Section 5.1.1, Previously Accepted Alternative Shutdown Capability QUESTION "As part of the Appendix A review process, some plants had committed to an alternative shutdown system in the form of a remote shutdown panel or remote shutdown system. Footnote 2 to Appendix R describes alternative shutdown capability as being associated with ' Rerouting, relocating, or modifying of(sic) existing systems.' To the extent that an existing remote shutdown system previously reviewed and approved under Appendix A to BTP 9.5-1 does not require modifications, rerouting, or relocating of existing systems, are the requirements of Section III.L of Appendix R backfit?"
1 Rev.G 6/24/98 3-44
____m__m
DRAFT BWROG
'{
Generic Guidance.for Post-Fire Safe Shutdown Circuit Analysis Assessment
~~RESPONSE~~
"Yes. Existing remote shutdown capabilities previously reviewed and approved under Appendix A to BTP APCSB 9.5-1 do not categorically comply with Section III.G.3 of Appendix R. Licensees were requested to re-analyze their plants to determine compliance with SectionIII.G. If the licensee chooses to use the option ofIII.G.3 for provision'6f safe
~
shutdown capability for certain areas, the criteria of Section III.L are applicable to that capability for that area..See"also the response to 5.1.3."
?
b L
il l
/
Generic Letter 86-10. Enclosure 2.L ppendix R Questions andAnswers, A
- Section 5.1.2. Pre-Existing Alternative Shutdown Capability. Also Generic Letter 85 01, Enclosure 6,? Appendix R Ouestions and Answers, Section 5.1:2. Pre: Existing Alternative Shutdown Capability h
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QUESTIONi N
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"Shmelice$j; i 0.ee :defib safe shutdown capability for p p.
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to!Section fII.GTriteri'a'a"s being composed of both the normal safe shIutdown#capadility and the pre-existing redundant or remote safe slintdodn capability which was previously installed as part of the
[p%5 dix A process. This definition often took the form of two ' safe shutdown trains' comprising (1) one of the two normal safe shutdown trahts, and (2) a second safe shutdown train ability which was being provided by the pre-existing remote shutdown capability. This definitional process, which was undertaken by a number oflicensees, makes a significant difference in the implementation of Appendix R.
Under such a definition, doesSection III.L criteria apply when the Commission did not call out Section III.L as a backfitT'
~~RESPONSE~~
"The definitional process mentioned considers an alternative shutdown capability provided under the Appendix A review as a redundant shutdown capability under the Appendix R review. This definitional process is incorrect. For the purpose of analysis to Section III.G.2 criteria, the safe shutdown capability is defined as one of the two normal safe shutdown trains. If the criteria of Section III.G.2 are not met, an altemative Rev.G 6/24/98 3-45
)
i DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment shutdown capability is required. The alternative shutdown capability may utilize existing remote shutdown capabilities and must meet the criteria of Sections III.G.3 and Ill.L of Appendix R. See also the response to 5.1.3."
Generic Letter 86-10. Enclosure 2, Appendix R Questions and Answers.
Section 5.3.11, Alternative /DedicatedShutdown v. Remote Shutdown Systems.' Also Generic Letter 85-01 Enclosure 6, Appendix R Questions and Answers. Section 5.3.11 Alternative / Dedicated Shutdown vs. Remote Shutdown Systems fF i..
c' I
i; QUESTION i;:
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"What is the diffei e tween alte e
dicate hutdown systems
_ required for fire phtection andlhe' remote shutdown,sjstems recommended under Chapter,7.ofthe SRP?"
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"'Il5e tem sh[ owrpsys}tems recommended under Chapter 7 of the
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w are needed to y GDC 19. These remote shutdown systems need to be reIdundadt'anf physically independent of the control room in order to gGDC 19. For GDC 19, damage to the control room is not
< considered. Alternate shutdown systems for Appendix R need not be redundant but must be both physically and electrically independent of the control room."
Information Notice 84-09,' Attachment 1, Section Vill. Applicability of10 CFR 50, Appendix R, Section111.L "Some of the inspected licensees had not considered Section III.L of Appendix R when attempting to meet Section III.G. The acceptance criteria for Section III.G.3, are listed in Section III.L. Although 10 CFR 50.48(b) does not specifically include Section III.L with Sections III.G., J, and O of Appendix R as a requirement applicable to all power reactors licensed prior to January 1,1979, the Appendix, read as a whole, and the Court of Appeals decision on the Appendix, Connecticut Light and Power, et al. v. NRC,673 F2d. 525 (D. C. Cir.), cert. denied (1982), does mean
. Rev. G 6/24/98 3-46
l DRAFT BWROG
{
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment l
that Section Ill.L applies to the alternative safe shutdown option under I
Section III.G."
SECY83-269, Attachment C. NRC StaWPositions on Post Fire Shutdown
. Capabilitv. Instrumentation Neededfor Alternative Shutdown Activities
]
,;y ;
I Section III.L of Appendix R requires provision for'dir'ect Nadings of the l
process variables necessary to perform and controi,the reactor shutdown l
function. The instrumentation needed to nieet this requirement was controversial on many of the alternative sh'utdown reviews. Thus, a Staff l
position was developed indicating the instrumentation required and a supporting justificati6n for some of the mbie controversial instrumentation l
was proyided (refsence:' memo /anda Rubenstein to Miattson, dated January ~7;g983, and March 13; 19,83). The followinglist of instrumentation was require +' n.
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h@ lff Instrumentation Needed for BWR
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Suppression pool level and temperature, c)fmergency or isolation condenser level, l
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Diagnostic instrumentation for shutdown systems, and e)
Levelindication for all L
I-SECY85-306. Enclosure 4, Interpretations ofAppendix R, Alternative or l
DedicatedShutdown o
l "Section III.G.3 of Appendix R provides for ' alternative or dedicated shutdown capability and its associated circuits, independent of cables, systems or components in the area, room, or zone under consideration.'
While ' independence' is clearly achieved where alternative shutdown equipment is outside the fire area under consideration, this is not intended to imply that alternative shutdown equipment in the same fire area but independent of the room or the zone cannot result in compliance with the regulation. The ' room' concept must be justified by a detailed fire hazards analysis that demonstrates a single fire will not disable both normal
{
shutdown equipment and the alternative shutdown capability."
Rev.G 6/24/98 3-47 1
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment Whitney to AlcKee Internal NRC Alemo of8/11/86. Enclosure 2. SECY 85-306 Afeeting Minutes of5/7/86 "It was stated that in fire areas for which alternative safe shutdown has not been provided, and exemption for Section Ill.G.2 of Appendix R is required if the separation features of Section Ill.G.2 are not provided.
This statement was challenged with the line of reasoning that i,f Section Ill.G.I.a of Appendix R is satisfied,Section III.G.2 need not be satisfied.
f i.
e ELD provided the following resolution'to this i uestikn: Interpretation l
Three of Appendix R (which defines the term " free of fire damage" in Section III.G.I.a.).was provide'd to clarify Section III.G.I.a, during the exemption process, Tor license 5; attenipting to justify the lack of III.G.2 separation fdatures fdr r"edunddnt trains within a single fire area.
,Jt Gis^never iritended that Nth"er methods proposed $y licensees" would be reviewed and approved at the Appendix R validation inspectibn. {o'r'ahy fire area a'n appfoved exemption is required where
[1II.G.2 e providEd."./*
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!neither ilternativisafe shutdowE nor the separation features of Section
[-
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k Russellio Novak Internal NRC hiemo of2/12/86, Proposed Generic Letter
,on Fire Protection Technical Specifications, Item 4 "A new specification has been included to address the limiting conditions for operation and surveillance requirements for the Alternate or Dedicated shutdown capability which is provided for some plants to meet the requirements of Section III.G.3 of Appendix R. Based on the defense in depth of fire prevention and protection which would preclude the need to use Alternate or Dedicated shutdown systems in all but the worst fire scenarios, the allowable out-of-service time for this shutdown capability is specified as thirty days. Further, in recognition that the single failure criteria is not applicable to the design of this shutdown capability and that under special circumstances continued plant operation may be justified, this specification has been written t permit continued plant operation subject to Commission approval. This provision permits consideration of the licensees actions and plans for restoring the system to operable status such that additional relief may be granted when justified without the need l
to process an emergency Technical Specification change."
]
Rev.G 6/24/98 3-48
DRAFT BWROG f
Generic Guidance for Post-Fire Safe s~
Shutdown Circuit Analysis Assessment l
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Shutdown Circuit Analysis Assessment
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DRAFT BWROG
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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.6 CONTROL ROOM FIRE CONSIDERATIONS A.
Regulations 10 CFR 50, Appendix R Section 11.D. Alternative or DedicatedShutdown Capability
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"In areas where the fire protection features cannot ensure l safe $hutdown capability in the event of a fire in that area, alternative or' dedicated safe shutdown capability shall be provided."
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~~r 10 CFR 50, Appendix R.-Section III.G.1, Fire" Protectio'n ofSafe Shutdown~~
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tw "1.iEire hr'otecti6n features shallie proUided for structures, systems, and h components'iniportant to safe shutdown. These features shall be capable
,f oflimitingfire' damage'so tliat: #
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Vy 4 ne. train of systems necessary to achieve and maintain hot a
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[f shutilown conditions from either the control room or emergenc
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control station (s) be free of fire damage; and d[
b.
Systems necessary to achieve and maintain cold shutdown from either the control room or emergency control station (s) can be repaired within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months ."
B.
Guidance Gencric Letter 85-01, Enclosure 6 Appendix R Questions and Answers, Section 3.8.4, Control Room Fire Considerations j
QUESTION "What considerations should be taken into account in a control room fire?
What is the damage that is considered? What actions can the operators take before evacuating the CR7 When can the centrol room be considered safe after a fire for the operator to return?"
t Rev.G 6/24/98 3-51
DRAFT BWROG Generic Guidance for Post-Fire Safe
')
Shutdown Circuit Analysis Assessment
~~RESPONSE~~
"The control room fire area contains the controls and instrumental redundant shutdown systems in close proximity (i.e. usually separation is a few inches). Because it is possible to provide shutdown capability that is physically and electrically independent of the fire ard., it is,our opiniori that altemative or dedicated shutdown capability and its associated circuits for the control room be independent of the cables system and components in the control room fire area.
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The damage to the system in the control room for a fire that causes evacuation of the control room cannot be predicted. A bounding analysis should be made to siissure that safibndition's c'an be miintained from outside the control roomi This indlysis is dependent td} sic) the specific
-desigri.* The. usual' assumption (sich are: E
/
~~1. ! The r tor l's pped in the ntro Bom.~~
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f' b Offsite poiver isilosJes'well as automatic starting of the onsite a.c.
2.b generators and tiiiautomatic function of valves and pumps who conNol cifcuits could be affected by a control room fire.
3 s
4
Jhe analysis should demonstrate that capability exists to manually achieve safe shutdown conditions from outside the control room by restoring a.c.
power to designated pumps, assuring that valve lineup is correct, and assuming that any malfunctions of valves that permit the loss of reactor coolant can be corrected before unrestorable conditions occur.
Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Any additional control room actions deemed necessary would have to bejustified under the exemption process.
After the fire, the operators could retum to the control room when the following conditions have been met:
1.
The fire has been extinguished and so verified by appropriate fire protection personnel.
Rev.G 6/24/98 3-52
(,
DRAFT BWROG Generic Guidance for Post-Fire Safe i
Shutdown Circuit Analysis Assessment 1
2.
The control room has been deemed habitable by appropriate fire l
protection personnel and the shift supervisor.
3.
Damage has been assessed and, if necessary, corrective action has been taken to assure necessary safety, control and information systems are functional (some operators may assist with these tasks) and the shift supervisor has authorized retum of plant control to the control room.
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s 4.
Tumover procedures which assure an orderly transfer of control from the altemate chutdown panel t'o the control room has been f(./
f completed.
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i After returning to the control room /the operators can take any actions
-. compatible,with the condition of the control room. Controls in any area (cabinet where thIfirioccurred would n'oi be available. Smoke and fire supNessantldamdey other/treas (cabihits) must also be assessed and
(-
corrective actiord.taken before controls in such cabinets are deemed functional./ CorNols insun'dhmaged area (cabinets) could be operated as required. Minormodifi$ations inside the control room may be performed to reach /old shutilown."
6 bd Jf Generic Letter 86-10. Eraciosure 2, Appendix R Questions and Answers.
Section 3.8.4. Control Room Fire Considerations 4
QUESTION o
"What considerations should be taken into account in a control room fire?
Wisat is the damage that is considered? What actions can the operators take before evacuating the CR7 When can the control room be considered safe after a fire for the operator to retum?"
~~RESPONSE~~
l l
"The control room fire area contains the controls and instrumental redundant shutdown systems in close proximity (i.e. usually separation is a few inches). Because it is possible to provide shutdown capability that is physically and electrically independent of the fire area, it is our opinion i
Rev.G 6/24/98 3-53
DRAFT BWROG Generic Guidance for Post-Fire Safe
}
Shutdown Circuit Analysis Assessment that altemative or dedicated shutdown capability and its associated circuits for the control room be independent of the cables system and components in the control room fire area.
.1 The damage to the system in the control room for a fire that causes evacuation of the control room cannot be predicted. A bounding analysis should be made to assure that safe conditions can be maintained from outside the control room. This analysis is dependent to (sic) the specific design. The usual assumption (sic) are: g
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The reactor is tripped in the control r5om/
[
1.
Offsite powerI[ lost as well 2.
auto ti starting f the onsite a.c.
generators and the automatic" function of valves andpumps whose
- geo6tN1 circuits could be iffehted b $a control roEriffire.
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The{ analysis lshould demonstrate that 9aphility exists to manua safe shutdon conditions from outsi~de the control room by restoring a.c.
)
poiver to design $ted pumpsfassuring that valve lineup is correct, and assuming,that afiy, malfunctions of valves that permit tl.: loss of reactor coolant can be corrected before unrestorable conditions occur.
YY
, Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. For any additional control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided.
Additionally, assurance would have to be provided that such actions could 1
not be negated by subsequent spurious actuation signals resulting from the postulated fire.
After the fire, the operators could return to the control room when the following conditions have been met:
1.
The fire has been extinguished and so verified by appropriate fire protection personnel.
2.
The control room has been deemed habitable by appropriate fire protection personnel and the shift supersisor.
Rev.G 6/24/98 3-54
DRAFT BWROG
~
f Generic Guidance for Post-Fir 'afe Shutdown Circuit Analysis Assessment 3.
Damage has been assessed and, if necessary, corrective action has been taken to assure necessary safety, control and information systems are functional (some operators may assist with these tasks) and the shift supervisor has authorized retum of plant control to the control room.
4.
Tumover procedures which assure an orderly transfeIof control from the alternate shutdown panel to the control room has'been completed. After retuming to the contiol room, the~ operators can take any actions compatible with the condition of the control room.
Controls in any area (cabinet where the fire occurred would not be available. Smoke and fire suppressant damage in hther areas (cabinets) mui;t also be asse'ssed and[c6rrective action taken before controls in such cabinets are deemed functional. ; Controls in
- (findamaged area.(cabinets 1chuld bfoperated asiequired. Minor r modifications.inside thefcontrol room may be performed to reach k told shutdow'n"'
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Conflictin'g Guidanc('
neric ette 5-01, Enclosure 6. Appendix R Questions and Answers,
,,Section 3.8.4, Control Room i tre Considerations
"... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Any additional control room actions deemed necessary would have to bejustified under the exemption process..."-
Generic Letter 86-10. Enclosure 2, Appendix R Questions and Answers, Section 3.8.4. Control Room Fire Considerations
... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. For any additional control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided. Additionally, assurance would have to be provided that such Rev.G 6/24/98 3-55
i DRAFT BWROG Generic Guidance for Post. Fire Safe
)
Shutdown Circuit Analysis Assessment actions could not be negated by subsequent spurious actuation signals resulting from the postulated fire..."
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DRAFT BWROG
(
Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.7 FREE OF FIRE DAMAGE A.
Regulations 10 CFR 50, Appendix R. Section 1H.G. Fire Protection ofSafe Shutdown Capability
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Fire protection features shall be provided for structures, systems, and components important to safe shutdown.' These features shall be capable oflimiting fire damage so that:
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One train of systems necessary't'opchieve an#d maintain hot a.
shutdowri conditions from eith'er th$ controlioom or
,., emerge'ncy @ntrol station (s) b'e free of fire $lamage...
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~~2. ;...one of thefollowing means of ensuring that one of the redundant I trainsIs fre$~odire daniage shalliejrovided:~~
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Separationbfca/
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bles and equipment and associated non-safety
/ circuits of fedundant trains by a fire barrier having a 3-hour f;!
[ rating" Structural steel forming a part of or supporting such fire 4 / barriers shall be protected to provide fire resistance equivalent
,.A to that required of the barrier; b.
Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustible or fire hazards.
In addition, firi detectors and an automatic fire suppression system shall be installed in the fire area; or c.
Enclosure of cable and equipment and associated non-safety circuits of one redundant train in a fire barrier having a 1-hour rating, In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area; l
l L
Inside noninerted containments one of the fire protection means specified above or one of the following fire protection means shall be provided:
Rev.G 6/24/98 3-57 l.
DRAFT BWROG Generic Guidance for Post-Fire Safe
}
Shutdown Circuit Analysis Assessment d.
Separation of cables and equipment and associated non safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustibles or fire hazards; e.
Installation of fire detectors and an automatic fire suppression system in the fire area; or i
f.
Separation of cables and equipment and associated non-safety circuits of redundant trains by noncombustible radiant energy h
shield.
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"The equipment and{ systems used to achieve and maintain hot standby
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copditionsfbot shutdownfor a BWR) should be (1) free of fire damage..."
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Generifletter 81-12 Enclosure 1. StaffPosition, Safe Shutdown
_Capbbility, Section 3. 7 "The equipment and systems used to achieve and maintain cold shutdown conditions should be either free of fire damage or the fire damage to such systems should be limited such that repairs can be made and cold shutdown conditions achieved within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Equipment and systems used prior to 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months after the fir (sic) should be capable of being powered by an onsite emergency power system; those used after 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months may be powered by offsite power."
Generic Letter 86-10, Enclosure 1, Interpretations ofAppendix R. Item 3, Fire Damage. Also Generic Letter 85-01. Enclosure 3, Interpretations of Appendix R. Item 3, Fire Damage
" Appendix R to 10 CFR Part 50 utilizes the term ' free of fire damage.' In promulgating Appendix R, the Commission has provided methods
)1 acceptable for assuring that necessary stmetures, systems and components I
Rev. G 6/24/98 3-58 1
l I
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DRAFT BWROG
~
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Generic Guidance for Post-Fire Safe Shutdown Circuit. Analysis Assessment l
are free of fire damage (see Section Ill.G.2a. b and c), that is, the structure, system or component under consideration is capable of performing its intended function during and after the postulated fire, as needed.
Licensees seeking exemptions from Section Ill.G.2 must show that the altemative proposed provides reasonable assurance that this criterion is met. (Note also that Section 111.0.2 applies only to equipmentneeded for hot shutdown. Therefore, an exemption from III.G.2 for c61d shutdown equipment is not needed.)"
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"Section III.G.1 ofAppendix R sta~s that one train ofiystems needed for hot shutdown mdEbefree offtre damage. Thus, one train of systems needed for Nt sh*utdhn muit be Sper,able'during and following a fire.
-(:
Operabilitybf thEhot shutdown.syst' ems, including the ability to overcome a fire or fire suphessAnt.ip'duced maloperation of hot shutdown equipment an'd the plant's po,wer liistribution system, must exist without repairs.
Manual o,peration of valves, switches and circuit breakers is allowed to j
operate equipment and isolate systems and is not considered a repair.
,Rosever, the removal of fuses for isolation is not permitted. All manual operations must be achievable prior to the fire or fire suppressant induced maloperations reaching an unrecoverable plant condition."
h
" Modifications, e.g., wiring change, are allowed to systems and/or components not used for hot shutdown, but whose fire or fire suppressant induced maloperations may indirectly affect hot shutdown. These repairs must be achievable prior to the maloperations causing an unrecoverable plant condition."
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Conflicting Guidance i
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DRAFT BWROG Generic Guidance for Post-Fire Safe
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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.8 FUNCTIONAL FAILURE STATES A.
- Regulations i
Not specifically addressed in any regulation.
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9 Generic Letter 86-10, Enclosure 2. Append +ix R Ou'estion'5 and Answers, it Section 5.3.1 Circuit Failure Modes. Also' Generic Letter 85-01,.. Appendix R Questions and Answers, Section 5.3.1, Circuit Failure Modes Qy ly j
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ass 0ciated bj spdriotis actuation?" "
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" Sections III.G.2 and III.L 7 of Appendix R define the circuit failur:
, motes as hot shons, open circuits, and shorts to ground. For consideration of spurious actuations, all possible functional failure states must be evaluated, that is, the component could be energized or de-energized by one or more of the above failure modes. Therefore, valves could fail open or closed; pumps could fail running or not running; electrical distribution breakers could fail open or' closed...."
Information Notice 92-18
...a fire in the control room could cause hot shorts, i.e. short circuits between control wiring and power sources, for certain motor-operated valves (MOVs) needed to shut the reactor down and to maintain it in a safe shutdown condition. If a fire in the control room forces reactor operators l
to leave the control room, these MOVs can be operated from the l
remote / alternate shutdown panel. However, hot shorts,' combined with the absence of thermal overload protection, could cause valve damage before
. Rev. G 6/24/98 3-61
. DRAFT BWROG Generic Guidance for Post-Fire Safe
)
j Shutdown Circuit Analysis Assessment the operator shifted control of the valves to the remote /altemate shutdown panel.
...an exarnple of the manner in which the motor of an MOV that is closed can be energized and damaged by a hot shon ifis overload protection is bypassed. The hot short bypasses the push button tha is normally used to close the MOV and thus provides power to the relay coil,Mhich closes those contactors that provide power to drive the motofinithe closed direction. Power will not be disconnected froin the motoE although it is stalled, because the same hot short bypassesthe torque sMtch. With the
. motor stalled, current and torque are abnormally high, hssibly causing the motor windings to fail and possibli' causing 2nechanical damage to the valve. This mechanic ~al ' amage inay be sufficient to pEvent reactor d
operators from maiiually operatih[the valve. ^ simildproblem can occur for.MOVs that arciopen (see F(gure 3). Siiorts to othE5ources of power canEso cause failure'of MO sf !;
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DRAFT BWROG
'(s Generic Guidance for Post-Fire Safe j
Shutdown Circuit Analysis Assessment j
i 3.1.9 CIRCUIT FAILURE MODES A.
Regulations 1
10 CFR 50, Appendix R, Section 111.G.2. Fire Protection ofSafe Shutdown Capability
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"...where cables and equipment, including associated non ' safety circuits that could prevent operation or cause maloperation due to hot shorts, open circuits, or shorts to ground, of redundant trains of systems necessary to achieve and maintain hot shutdown conditions 2."
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"T# safe shutdod5quipme' t and systS(is for each fire area shall n
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kndwn to be isolated'from associaIeII non-safety circuits in the fire area so tha*t hot shdrts, dpen circuils!or shotts to ground in the associated circuits will not pr. event operation of the safe shutdown equipment."
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, Guidance NUREG-0800. SRP, Section 9.5.1, Section C.S.c. 7, Alternative or DedicatedShutdown Capability
"...The safe shutdown equipment and systems for each fire area should be knowa te be isolated from associated circuits in the fire area so that hot shors,, open circuits, or shorts to ground in the associated circuits will not prevent operation of the safe shutdown equipment..."
Rev.G 6/24/98 3-63 t
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9 DRAFT BWROG Generic Guidance for Post-Fire Safe
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Shutdown Circuit Analysis Assessment I
Generic Letter 81-12. (first page ofcover letter)
"... where cables or equipment, including associated non-safety circuits, that could prevent operation or cause maloperation due to hot shorts, open circuits or shorts to ground or (sic) redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located.within the same fire area outside of primary containment..."* <[]
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should read "of redundant trains". / pj f
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- Section 53.'1, Circuit Failure Modes. Also GenericLetter 85-01,. Appendix R Questions and: Answers, Section 5.3.1, Circuit Faildre Modes V %
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"What cir,cuit. failure modes must be considered in identifying circuits a.isocidbd by spurious actuation?"
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" Sections III.G.2 and III.L.7 of Appendix R define the circuit failure modes as hot shorts, open circuits, and shorts to ground. For consideration of spurious actuations, all possible functional. failure states must be evaluated, that is, the component could be energized or de-energized by one or more of the above failure modes. Therefore, valves could fail open or closed; pumps could fail running or not running; electrical distribution breakers could fail open or closed. For three-phase AC circuits, the probability of getting a hot short on all three phases in the proper sequence to cause spurious operation of a motor is considered sufficiently low as to not require evaluation except for any cases involving Hi/Lo pressure interfaces. For ungrounded DC circuits,ifit can be shown that only two hot shorts of the proper polarity without grounding could cause spurious operation, no further evaluation is necessary except for'any cases involving Hi/Lo pressure interfaces."
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Rev.G 6/24/98 3-64
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DRAFT BWROG
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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment Generic Letter 86-10. Enclosure 2, Appendix R Ouestions and Answers, Section 5.3.8, Short Circuit Coordination Studies. Also Generic Letter 85-01, Enclosure 6. Appendix R Ouestions at:d Answers, Section 5.3.8.
Short Circuit Coordination Studies QUESTION c
g ?~1 "Should circuit coordination studies consider high imped $$ce faults?"
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~~RESPONSE~~
e l-5 "To meet the separation criteria ofSectionlll.G.2 and III.G.3 of Appendix R, high impedance faultsshould be considered for all associated circuitsjocated in the fire area of ncern.- Thus, simultaneous high impedance faults (below the tripy@oint for the breaker on eac s
circuit) for all associated circu'its located in the fire area should be cons' idered in the'eUaluation ff thisafeShutdown capability. Clearing
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such faults hn associited circuitswhich may affect safe shutdown may be accomplish'ed by man'ual, breaker trips govemed by written procedures.
Circuit coordination snidies need not be performed ifit is assumed that sliutdowicapability will be disabled by such high impedance faults and appjoyiiate written procedures for clearing them are provided."
y EGhi98-002, AfEAf0RANDUhf TO: Hubert J. Miller, Regional Administrator FROM: James Lieberman, Director, Office ofEnforcement
~~SUBJECT:~~
ENFORCEAfENT GUIDANCE AfEh10RANDUAi-DISPOSITION OF VIOLA TIONS OF APPENDIX R, SECTIONSIII.G AND III.L REGARDING CIRCUITFAILURES
" Office of Nuclear Reactor Regulation (NRR) staff and regional inspectors have found a number of plant specific problems related to potential fire-induced electrical circuit failures which could prevent operation or cause maloperation of equipment needed to achieve and maintain l
post-fire safe shutdown. Fire protection inspections conducted in each l
Region have found that there may exist noncompliance with the regulations that require that facilities be designed such that fire-induced circuit failures (e.g., hot shorts, open circuits, and shorts to ground) will not preclude the ability to achieve and maintain a safe Rev.G 6/24/98 3-65 l
DRAFT BWROG Generic Guidance for Post-Fire Safe
)
Shutdown Circuit Analysis Assessment shutdown condition. This memorandum is being issued to provide enforcement guidance concerning inspection findings pertaining to the inability to achieve and maintain safe shutdown conditions due to potential fire-induced circuit failures.
An example of the consequences of this type problem is reported in Information Notice (IN) 92-18, " Potential for Loss of Rern6te' Shutdown Capability During a Control Room Fire," whichalerte'd licensees that the circuit logic associated with certain motor-op'erated valves, when subjected to a single fire-induced hot short,'could result in a spurious permissive signal. The spurious signal could cause the valve to operate, bypassing the protective features, and resulting'in mech'anical valve damage. Such firennduced damagfcould irhpair the capability to shut i
~~ 4?' plant andmaintain it in a' safe shutdown condit down the f
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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.10 ASSOCIATED CIRCUITS A.
Regulations 10 CFR 50, Appendix R. Section Ill.G.2. Fire Protection ofSafe Shutdown Capability
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"...where cables or equipment, including associated non-silfety circuits that could prevent operation or cause maloperatiori due tdhot shorts, open circuits, or shorts to ground, of redundant trhins of systeins necessary to achieve and maintain hot shutdown'conditi6ns are located within the same fire area outside of primary contair'unent..bM]
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Separation ofcables and equipmenjand associated non-safety a.
egcircuits of rdlundant train;s by a firey arier having a 3-hour rating...
les anE Innd associated non-safety
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Depar on m
" circuifs of feduhdant tiainshy'i horizontal distance of more than 20 e feet with nEintervenihg combustible or fire hazards. In addition, fire detec' tors $nd an'iditomatic fire suppression system shall be installed
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Enclosure of cable and equipment and associated non-safety circuits of one redundant train in a fire barrier having a 1-hour rating, In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area; Inside noninerted containments one of the fire protection means specified above or one of the following fire protection means shall be provided:
d.
Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustibles or fire hazards; e.
Installation of fire detectors and an automatic fire suppression system in the fire area; or j
l f.
Separation of cables and equipment and associateil non-safety circuits
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of redundant trains by a noncombustible radiant energy shield."
l Rev.G 6/24/98 3-67 i
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DRAFT BWROG Generic Guidance for Post-Fire Safe
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Shutdown Circuit Analysis Assessment l
B.
Guidance Generic Letter 81-12. Enclosure 2. Requestfor AdditionalInformation.
Request No.1 "Section Ill. G of Appendix R to 10 CFR Part 50 requires cabling for or associated with redundant safe shutdown systems necessaiy~tolachieve and maintain hot shutdown conditions be separated by fire barriers'having a three-hour fire rating or equivalent protection (see Sectioh III.G.2 of Appendix R). Therefore, if option Ill.G.3 is chosen for the protection of shutdown capability cabling required for or associated with the altemative method of hot shutdown for each fire arcaimust be physically separated by the equivalent of a'three-hourirated fire banier from the fire area.
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hG Hn evsluiting altemative shutdown methods, associated circuits are circuits that!could prevent opsration oi cause maloperation of the altemative train
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induced ho} shorts, open circuitar shorts to ground.
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,Section III.G.2 of Appendix R to 10 CFR 50 and have either (1) a common power source with the alternative shutdown equipment and the power source is not electrically protected from the post-fire shutdown circuit of concern by coordinated circuit breakers, fuses or similar devices, (2) a connection to circuits of equipment whose spurious operation will adversely affect the shutdown capability, e.g., RHR/RCS Isolation Valves, or (3) a common enclosure, e.g., raceway, panel, junction box, with alternative shutdown cables and are not electrically protected from the post-fire shutdown circuits of concern by circuit breakers, fuses or similar devices.
For each fire area where an altemative or dedicated shutdown method, in accordance with Section III.G.3 of Appendix R to 10 CFR Part 50, is provided by proposed modifications, the following information is required to demonstrate that associated circuits will not prevent operation or cause maloperation of the altemative or dedicated shutdown method:
DRAFT BWROG 3
- Generic Guidance for Post-Fire Safe I
y Shutdown Circuit Analysis Assessment A.
Provide a table that lists all equipment including instrumentation and j
support system equipment that are required by the alternative or dedicated method of achieving and maintaining hot shutdown.
B.
For each alternative shutdown equipment listed in 1.A above, provide a table that lists the essential cables (instrumentation, control and power) that are located in the fire area.
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Provide a table that lists safety related a'nd non-safety related cables associated with the equipment and cables constituting the attemative
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or dedicated method of shutdown that are jocated in the fire area.
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Show that fitjI E[h3ced failures of tif,iables listed in B and C above i
D.
will not prevsnt operation;or;cause maloperationfof the altemative or i
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E. fFor eb ca(eYisted in#1.B above,hiovide detailed ele p
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SECYs3-269, Attachment C, NRCStaffPositions on Post Fire Shutdown
, Capability. Protectionfkom AssociatedNon-Safety CircuitsSection III.O and III.L indicate the need for protection for associated l
non-safety circuits whose failure could prevent operation or cause maloperation of the systems needed for safe shutdown. Due to confusion over what constitutes an associated circuit, the staffissued a clarification.
The clarification provided 1) a definition of associated circuits for l
Appendix R consideration,2) the guidelines for protecting the safe shutdown capability from the fire induced failures of associated circuits l
and the information required by the staff to review associated circuits, (reference: memorandum, R Mattson to D Eisenhut, March 22,1982).
1 C.
Conflicting Guidance J
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Rev.G 6/24/98 3-69 l'
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l Shutdown Circuit Analysis Assessment
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Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3,1.11 HOT SHORT DURATION A.
Regulations l
Not specifically addressed in any regulation.
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Guidance g 'f
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^, Appendis R Questions and Answers Section 5.3.2, 'Ifor Short' Duration w
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~~RESPONSE~~
l? g j. ",We.would postulate that a ' hot short' condition exists until action has ,$eeYtaken to isolate the given circuit from the fire area, or other actions as appropriate have been taken to negate the effects of the spurious actuation. We do not postulate that the fire would eventually clear the ' hot short.'" { 1 C. Conflicting Guidance ) l 1 i 1 l Rev.G 6/24/98 3-71 i l
s l DRAFT BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment l , 7y.,} ..t /, j'r } ,1 y gi t ,e i; j y / t .4 1 /: y +' s ,.e y: I f,: p j r. ls p .1 )b ( l, f:9 ,W' / Yi. [lic'$ .h", V_.,,fi I h: l 7 i? i. u I LP - ') /
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l DRAFT BWROG ( Generic Guidance for Post-Fire Safe I Shutdown Circuit Analysis Assessment I 3.1.12 UNGROUNDED DC CONTROL CIRCUITS A. Regulations Not specifically addressed in any regulation. , e /, a. i B. Guidance i ,c ?g ! ) y x Generic Letter 86-10, Enclosure 2 Appendix R Qu'estions and Answers, Section 5.3.1 Circuit Failure Afodes. Also Generic Letter 85-01,, Appendix R Ouestions and Answers, Section 5.3.1 Circuit Failure Afodes Q u l. ff f p [ [f j! .f p;
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ja "Whdt circuit faihiremodes must be considered in identifying circuits { associated by sptiriotIs actuationJ"> ' k E kp RESPON E 3 y ".I..For' ungrounded DC circuits, ifit can be shown that only two hot ,o'f-th7 proper polarity without grounding could cause spurious operation, no further evaluation is necessary except for any cases involving Hi/Lo pressure interfaces." Boger to Martin Internal NRC hiemo of1/16/91. Requestfor Assistance: Determine Whether Two Hot Shorts in a Multiconductor Cable Associated with a Non-HULow Pressure Interface Should Be Anal _nedfor Fire induced Spurious Actuation (Generic Letter 86-10, Section 5.3.1, Non-Hi/ Low Pressure Interfaces in Ungrounded AC and DC Circuits) j "...We have reviewed this issue and concluded that two hot shons in a multi-conductor cable associated with a non-high/ low pressure interfao should be analyzed. This conclusion is consistent with the intent of G. L. 86-10, Section 5.3.1. Section 5.3.1 states that for ungrounded DC circuits, ifit can be shown that only two hot shons of the proper polarity without Rev.G 6/24/98 3-73 1 l
l DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment grounding could cause spurious operations, no further evaluation was necessary except in cases involving high/ low pressure interface." " Exempting ungrounded DC circuits (the type circuit in question at D. C. Cook) from analysis of the consequences of two hot shorts of the proper polarity was based on the assumed low probability of occurrence. The staff was considering single conductor cables in this position,mnele it clearly would not be probable to get multiple shorts of two conductors (of the same polarity) without shorting to ground. ;The probability of such an event occurring is clearly greater in the case of multi-codductor cable with the conductors in close proximity to,other and potentially affected simultaneous by the postulated fire.< This position is consistent with the position outlined i([a~ notice of viointion to the[Dresdeniplant dated -of a targht f,1989 (Ilem fjpage 2)) whereiE'a potential for sp - January.3, ock relief valve could result firom two hot shSrts in a multiple / conductor cable.'Rf /" r h y ' y J.A>* j r y rp / r F ) C. Co'nflicting Guulance'i.y t-p v & y b fl .a-y 1. 1 1 J j Rev.G 6/24/98 3-74 i
DRAFT BWROG j ( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment l 3.1.13 HIGH/ LOW PRESSURE INTERFACE A. Regulations 10 CFR 50. Appendix R. Section Ill.L Alternative and Dedicated Shutdown Capability /$ ? f] "1. Altemative or dedicated shutdown capability providdd for a specific fire area shall be able to...(b) maintain react' r coolant inventory..." o r g i "...During the postfire shutdown, the reactor coolant system process variables shall be maintained within.those predicted for a loss of normal a. ce p' wer, and thefission product boundary integrity shall o not be affected; i.e.; there shall be no fuel clad damage, rupture of .drif primary [ coolant boun(dah, of rupture of the' containment hboundary."44 f@ h k p;" ,y - :z_ [j' /g fu; p ( y B. G idanceIE [ t( l:.. GenericLetter'81-12 Enclosure 2, Requestfor AdditionalInformation, Requent No. 2 I A" "The residual heat removal system is generally a low pressure system that interfaces with the high pressure primary coolant system. To preclude a LOCA through this interface, we require compliance with the recommendations of Branch Technical Position RSB 5-1. Thus, this interface most likely consi'sts of two redundant and independent motor operated valves. These two motor operated valves and their associated cable may be subject to a single fire hazard. It is our concern that this single fire could cause the two valves to open resulting in a fire-initiated LOCA through the subject high-low pressure system interface. To assure that this interface and other high-low pressure interfaces are adequately protected from the effects of a single fire, we require the following information: l A. Identify each high-low pressure interface that uses redundant electrically controlled devices (such as two series' motor operated j Rev.G 6/24/98 3-75 l
DRAFT BWROG Generic Guidance for Post-Fire Safe } Shutdown Circuit Analysis Assessm'ent valves) to isolate or preclude rupture of any primary coolant boundary. B. Identify the device's essential cabling (power and control) and describe the cable routing (by fire area) from source to termination. A' C. Identify each location where the identified cables.arNe';iarated by less than a wall having a three-hour fire rating from cables for the redundant device. <q;f' }l f j y D. For the areas identified in item 2.C above,(if any),yrovide the bases and justifications to the acceptability of:the existing design or any proposed modifications." E ff ) [f fin P S h f .c . qf~%- F lJ l f f s Generic Letter 86210,TEnclosfe,2, Appendix R Questions and Answers, Section 5.3.'10, Design Basis!Planf Trarisients. Also Generic Letter 85-01, Enblosure 6; Appendit R Questioits'and Answers, Section 5.3.10, Design ~} Basis Plant Transienisf bESTIN )y at plant transients should be considered in the design of the alternative or dedicated shutdown systems?"
~~RESPONSE~~
"Per the criteria of Section~ III.L of Appendix R a loss of offsite power shall be assumed for a fire in any fire area concurrent with the following assumptions... c. The safe shutdown capability should not be adversely affected by a fire in any plant area which results in spurious actuation of the redundant valves in any one high-low pressure interface line." l Rev.G 6/24/98 3-76 I 4
L DRAFT BWROG I Generic Guidance for Post-Fire Safe q Shutdown Circuit Analysis Assessment Information Notice 87-50 ...lf the postulated fire causes a hot short which opens a high pressure to low-pressure system interface isolation valve, exposure of the low-pressure system to pressures in excess ofits design pressure could result in a LOCA..." x: i ~- ...the fission protect boundary integrity shall not be affected, i.e., there shall be no rupture of any primary coolant boundary." Thus, for those iow-pressure systems that connect to the reactor coolant system (a high-pressure system), at least one isolation valve must remain closed despite any damage that may.be caused by fire. A' fire could occur in the panel or cables that control the~ isolation va{ses capsing[ hot shorts that may result in the opening the valves at the high/ low-pressure interface., Since the low- -pressure system efuld.be designed for p:5ssures as low as 200 to 400 psi, the high pressure;fr_odthe reactorgoolant system approximately 1000 to 1200, psi for BWRs and 2000 to 2200 psi for PWRs) could result in failure' ( of the low-j'resstire piping.jIn min ' instances, the valves at the high-pre'ssure tojlow-Ness %' pressure and flow conditions interface are not designed to close against full reactor coolant system opening couldTesult in a LOCA that cannot be isolated, even if control of ths valv ,q? e can be reestablished." C. Conflicting Guidance l[ ,t Rev.G 6/24/98 3-77 I
I DRAFT BWROG Generic Guidance for Post Fire Safe ) Shutdown Circuit Analysis Assessment l s. ,, es: g,_, x e ...p. w ,a f [. ./.B LA F d'"j.. /t-j ~j r. k I l l i j6 I: n ,, r~.. t; t i ~ a.- y E Y {k? ? ?; h L:
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DRAFT BWROG ^ f Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment l 1 .3.1.14 VESSEL LEVEL ABOVE TOP OF ACTIVE FUEL i i A. Regulations 10 CFR S0, Appendix R. Section Ill.L.2. Alternative and Dedicated Shutdown Capability

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$i 0-In the course of performing Appendix R, safe shutdown reviews, the Auxiliary Systems Branch has nothd that various boiling', water reactor facilitie; propose the use of. ADS in. conjunction pith LPClas their proposed altemate shutdown -methodin order t$ achieve and maintainhfe shutdown following a fire event in certain p"ortioniofihe plant [For somEcases this strategy will result in a shoft-term uncovlil of thehppe'r'popioE of the core during depressurization. fE k p / N -) Analyses ofsi events: discussed in the reference give results which inaicate tidit theincoviry time is short enough and the amount of fuel u$coveredis sEdii enough, that cladding integrity would not be ti$reatefied. The " lettered" requirements of Appendix R, however, would . joi$ satisfied since Section III.L states:
1. "...During the postfire shutdown, the reactor coolant system process variables shell be Maintained within those predicted for a loss of normal AC power...., and

2. "The reactor coolant makeup function shall be capable of maintaining the reactor coolant level above the top of the core for BWRs..."

The use of ADS and LPCI would not be the preferred means of maintaining reactor core cooling. Nevertheless, the use of ADS and LPCI is an approved and accepted means of achieving and maintaining safe shutdown conditions, and does comply with certain provisions of Section Ill.L of Appendix R regarding fission Product boundary integrity. Based on the above, for those licensees who have proposed the use of ADS and LPCI for alternate shutdown in the event of a fire, we consider ] Rev.G 6/24/98 3-80 DRAFT BWROG 'g Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment their proposal as a request for an exemption to the requirements of the above referenced portion to Section Ill.L of Appendix R, and intend to grant such exemptions. Whitney to AlcKee Internal NRC Alemo of8/11/86. Enclosure 2. SECY 85 306 Afeeling Afinutes of5/7/86 .c q , f f "Some attendees expressed concem over approved BWR ADS /LPCI post-fire safe shutdown configurations. Attendees were assured that fuel rod tests had been performed to assess the pote'ntialfor core l damage arising from short term partial. core uncovery. DI contacted RES and developed the following infodnaiion: / f... ff) [E DrIohrt Ya Ho ten of the uel S tems Resear h Branch of the Divisioh of AEcident Evaluation, Office of Nuclear Regulatory .Ilt:searchl42M4b3) is anliuthority_in this area. He states that fuel rod ( Itesting has been conducted for many years at the National Reactor [Univer$al at[ tine dialkdiver (U.S.) National Laboratory in Chalk JRiverpCanak Uyto 32 bundled light water reactor fuel rods have

~~been tested for short time periods in partial steam cooling mode with~~

[: sim'ulated 100% power history decay heat. The cladding panially ,Foxidized but no fuel damage resulted." C. Conflicting Guidance C Rev.G 6/24/98 3-81 DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment 1 1 l l l l ,.c,. c p.; '* F.. h ~,. - j y-A, 4_: p + ,f; .i.. i N} .h(' gg*; j; 1; g'.. l? y i: / p. s r.h,k / s. ~ c'?'.T. -'v; a. f,j, / V ,'Lp r jp - g F b,y L ~? a k .~ iv;. i n. );

~~g L~~

ff l4 ,f.:: -~~ l f. y. ,av f' _f I )I Rev. G 6/24/98 3-82 l l t l I DRAFT BWROG l{~ Shutdown Circuit Analysis Assessment Generic Guidance for Post-Fire Safe i 3.1.15 USE OF ADS /LPCI FOR HOT SHUTDOWN 4 A. Regulations Not specifically addressed in any regulation. i a ,F, f,,r *,.c g l B. Guidance ,e k 4 y, h SECY83-269. Attachment C NRCStaWPbsitions bn'Po t Fire Shusw.vn Capability. Use ofAutomatic Depressuri:ation Systems (ADS) and Low Pressure Coolant Injection (LPC1) DuriniSafe Shutdown Operations

W

/p

}

jd In the course of performing Appen' dix R, fe shutdown' reviews, the staff noted thiftpous[boiliAg water reactor ilities propose'the use of ADS in, conjunction with LPCI as their proposed alternate shutdown method in orddr.to achihve a'nd maintain safe shutd$wn following a fire event in ^ ceriain portI5ns df th'iplant! Forsome' cases this strategy will result in a sh$n-term Eicoverin[of th'e uphr portion of the core during r dejressuri$atiou, TheYleEered" requirements of Appendix R would not be satisfie'd since'Section III.L states: hf 'hp...During the positive shutdown, the reactor coolant system process variables shall be maintained within those predicted for a loss of normal AC power... ", and

~~2. "The reactor coolant makeup function shall be capable of maintaining the reactor coolant level above the top of the core for BWRs..."~~

Analysis of similar events indicate that the recovery time is short enough and the amount of fuel uncovered is small enough, that cladding integrity would not be threatened. The use of ADS and LPCI would not be the preferred means of maintaining reactor core cooling. Neverless, the use of ADS and LPCI is an approved and accepted means of achieving and maintaining safe shutdown conditions, and does comply with certain provisions of Section III.L of Appendix R regarding fission product boundary integrity. Rev.G 6/24/98 3-83 f l DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment Therefore, the use of ADS and LPCI was considered to be an acceptable alternative shutdown capability. . Rubenstein to Mattson. Internal NRC Memo of12B/82. Use ofAutomatic Depressurization System (ADS) and Low Pressure Coolant Injection (LPCI) to Meet Appendix R. Alternate Shutdown Goals.q 't 46Yf - In the course of performing Appendix R, safe shutdown reviews, the Auxiliary Systems Branch has noted that various boiling water reactor facilities propose the use of ADS in conjunction with'LPCI as their proposed altemate shutdown method in order to achieve and maiintain safe shutdown'following a fire event in certain portions,6fihefplant. %someyased this str5tegy will result in a shon-term uncovering df the upperportion of the coreMuring depressurization. hf hf Y -AfQ Analyses ofsimilar events disc {ussied in the reference give r indidate thafthe dIricovery tin $e is khor;d66 ugh and the amount of fuel uniiivered fismAll eMugh,ihatpl5d' ding integrity would not be ') threatened [fied smce $Ec, tion III L states:ThefletteI$d"/ req naffbe satis f 'ng the postfire shutdown, the reactor coolant system process. Y [.l' g L. variables shell be Maintained within those predicted for a loss of normal AC power...., and

~~2. "The reactor coolant makeup function shall be capable of maintaining the reactor coolant level above the top of the core for BWRs..."~~

The use of ADS and LPCI would not be the preferred means of maintaining reactor core cooling. Nevertheless, the use of ADS and LPCI is an approved and accepted means ofachieving and maintaining safe shutdown conditions, and does comply with certain provisions of Section Ill.L of Appendix R regarding fission Product boundary integrity. Based on the above, for those licensees who have proposed the use of ADS and LPCI for alternate shutdown in the event of a fire, we consider their proposal as a request for an exemption to the requirements of the above referenced portion to Section III.L of Appendix R, and intend to grant such exemptions. ] Rev.G 6/24/98 3-84 i DRAFT BWROG e( ' Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment i Whitney to AlcKee Internal NRC Alemo of8/11/86. Enclosure 2. SECY85-306 Afeeting Afinutes of5/7/86 "Some attendees expressed concern over approved BWR ADS /LPCI post-l fire safe shutdown configurations. Attendees were assured that fuel rod tests had been performed to assess the potential for core damage arising from short term partial core uncovery. DI contacted RES and developed the following information: pfh' l ,g 4 ? N Dr. Robert Van Houten of the Fuel Systems Research3 ranch of the Division of Accident Evaluation, Offic' of Nuclear Regulatory ~ e Research (427-4463)is an authority in this aiea. He states that fuel rod testing has beeri conducted formany years at the National Reactor Uniyersal at thji Chdlk River'(U.S.) National Laboiatory in Cnalk -, Rise ~r,'CanadaR Upt time. periods in%ial steam co to 32 bundled light water reactor fuel rods have been tested fo$shor $1mulatEd 1005ilower history'decayfeat. The cladding partially

~~,'(~~

[ oxidized butbo fuel daniagens61ted." rl ll.ml }}' C. Conflicting G6idance ,f t i I Rev.G 6/24/98 3-85 1 l l DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment { l /V ,ri pl^ y [ \\ l t t. f / i: l H Y# Y { g? y ' b;; [f'*'T jf-

~~s..~~

t b. !yD f. 6: . - af * -w~f fv' p$ l} [ ,0 " l P H A" t-g l [? .V' l,% F' J' }} '. - [ F" ) eV"' t? ~ ,T. s:sw llp#j.. j l l l l l Rev.G 6/24/98 3-86 u DRAFT BWROG ( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.16 DESIGN BASIS PLANT TRANSIENTS A. Regulations Not specifically addressed in any regulation. . : c d' B. Guidance ,a f I 3.-v y e \\l t' Generic Letter 86-10. Enciesure 2. Appendix R Questions and Answers, Section 53.10, Design Basis Plant Transients. Also Generic Letter 85-01,. Appendix R Questions and Answers, Section 53.10, Design Basis Plant Transiently ll j') y W LT / O ]% ,Qt}ESTIOG [l p j; U{ y b E) l~y "What plan \\tt tramiisiits should be considered in the design of the ( or dedicated shutdowh systy'ms?"AV ~ .N bl hf

~~RESPONSE~~
b;. f 9 t r ",Per,ths criteria of Section III.L of Appendix R a loss of offsite power ,sbs!!~be assumed for a fire in any fire area concurrent with the following assumptions: a. The safe shutdown capability should not be adversely affected by any one spurious actuation or signal resulting from a fire in any plant area; and b. The safe shutdown capability should not be adversely affected by a fire in any plant area which results in the loss of all automatic function (signals, logic) from the circuits located in the area in conjunction with one worst case spurious actuation or signal resulting from the fire; and c. The safe shutdown capability should not be adversely affected by a 1 l fire in any plant area which results in spurious actuation of the l redundant valves in any one high-low pressure interface line." (_ l l Rev.G 6/24/98 3-87 l
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment Generic Letter 86-10. Enclosure 2. Appendix R Questions andAnswers, Section 7.1 Fire Protection andSeismic Events. Also Generic Letter 85-
~~01. Enclosure 6, Appendix R Questions andAnswers. Section 7.1, Fire Protection andSeismic Events QUESTION~~
~~,.y ,.f y w : For which situations other than the reactor coolant pump kbe oil system are seismic events assumed to be initiators of a fire? ' p j l/l !e / h~~
~~RESPONSE~~
The guidelines for thheismic des lign of fire pr'otection9ystems which .6 cover other general; situations is! elineated in BTP CMEB 9.5-1 C.I.C(3) d <C ' and4)! )} nwl l[ s 1 "(3) As a nu(nimum,pe fire s/, b r.: h c uppressign sistem should be capable of delivering Waterfo minual 150se,s0dions located within hose reach of areas ) containinghuipmentyequbed for safe plant shutdown following the safe ~ s$tdown earthjuake (SSE). In areas of high seismic activity, the staff j will consider oir a case-by-case basis the need to design the fire detection alui sul pression systems to be functional following the SSE. f Y (4) The fire protection systems should retain their original design capability for (a) natural phenomena ofless sey. rity and greater frequency than the most severe natural phenomena (approximately once in 10 years) such as tomadoes, hurricanes, floods, ice storms, or small intensity earthquakes that are charai:teristic of the geographic region, and (b) potential man-made site related events such as oil barge collisions or aircraft crashes that have a reasonable probability of occurring at a specific plant site. The effects oflightning strikes should be included in the overall plant fire protection program: We have considered California as being a high seismic activity area. For those plants reviewed under Appendix A, our position is (A.4): Postulated fires or fire protection system failures need.not be considered concurrent with other plant accidents or the most severe natural phenomena. ] Rev.G 6/24/98 3-88 l L
' ~ DRAFT BWROG Generic Guidance for Post-Fire Safe 4 - Shutdown Circuit Analysis Assessment i I Our guidelines on the seismic design of fire protection systems installed in safety related areas are delineated in Regulatory Guide 1.29, " Seismic Design Classification," paragraph C.2. The failure of any system should not affect a system from performing its safety function. i, 1 Our guidelines on the seismic design of hydrogen lines is deligeated in BTP CMEB 9.5-1 Section C.S.d(5): f" 3 (5) Hydrogen lines in safety-related areas shou e the designed to j seismic Class I requirements, or sleeved such that the outer pipe is directly ) . vented to the outside, or should be, equipped with excess 11ow valves so that in case of a line break, the hydrogen concentration 01 the affected areas will not excedi 29.. /j [f' ] [? [? !N [ 5,, n all PWRs have a hydrogen line going to the Volume C6ntrol Tank (Make-up Tank) thatmeds to be protected. Toiidentifytplanp(pecific situationsin which seismic eve F j;r p / VP l{ L' a fire in a specific plaht are# the fire protection engineer and systems a engineer pErfordning thE fire hazards analysis should be concerned with in-situ combustible" materials which can be released in a manner such that tdey,sould contact in-situ ignition sources by a seismic event. An example ) jf this would be the rupture of the RCP lube oil line directly above the hot i reactor coolant piping. The fire protection engineer should also be concemed with seismic induced ignition sources, electrical or mechanical, which could contact nearby in-situ combustible materials. 'It should be noted that the guidelines cited above from BTP CMEB 9.5-1 are not applicable to plants reviewed and approved under BTP APCSB 9.5-1." Generic Letter 86-10 Enclosure 2, Appendix R Questions and Answers, Section 7.2, Random Fire andSeismic Events. Also Generic Letter 85-01,, Appendix R Questions and Answers, Section 7.2. Random Fire andSeismic Events QUESTION "Is a random fire to be postulaMd concurrent with a seismic event?" Rev.G 6/24/98 3-89 l
I DRAFT BWROG l Generic Guidance for Post-Fire Safe ) l Shutdown Circuit Analysis Assessment l
~~RESPONSE~~
l "Our position, as stated in Section C.I.6 of BTP CMEB 9.5-1, is " Worst case fire need not be postulated to be simultaneous with non-fire related failures in safety systems, plant accidents, or the most severe natural phenomena." .M g.; ( h^ Where plant systems are designed to prevent the release of combustible materials caused by a seismic event, such as5 dike'aroun'd a fuel oil tank transformer, or seismic supports for hydrogen lines, then'no fire need to be arbitrarily assumed to take place in the fire hazards analysis. IQ hi Because it is impodible to comple'tely prehl'udt the occ^urrence of a - gf}y induce' fire',Sectiori d.6.c(4forCMEB 9 %! states: seismicall dj: y l} ll S' confections'should beinade tpsujiply waier at least to standpipes and " Provisions for riuiniuti fire fighting irlifeTis containing equipment reqitired forIsafehlarit shutdownin the event of a safe shutdown ) eaithquake@The piping system serving such hose stations should be arialyzed for SSE, loading and should be provided with supports to ensure system ssurfintegrity. The piping and valves for the portion of hose sfiin pe system affected by this functional requirement should, as a ,$iirlimum, satisfy ANSI B31.1, ' Power Piping.' The water supply for this condition may be obtained by manual operator actuation of valves in a connection to the hose standpipe header from a normal seismic Category I water system such as the essential service water system. The cross connection should be (a) capable of providing flow to at least two hose stations (approximately 75 gpm per hose station), and (b) designed to the same standards as the seismic Category I water system; it should not degrade the performance of the seismic Category I water system." The post-seismic procedures should include a damage survey, and a determination of whether any fires were initiated as a result of the seismic event. See also the response to Question 7.1. It should be noted that the guidelines cited above from BTP CMEB 9.5-1 are not applicable to plants reviewed and approved under BTP APCSB 9.5-1. Rev. G 6/24/98 - 3-90
g DRAFT BWROG t, Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment Whitney to AlcKee Internal NRC Afemo of8/11/86. Enclosure 2, SECY 85 306 Afeeling Afinutes of5/7/86 "It was noted that the three assumptions of Question and Answer 5.3.10 are meant for independent use (that is, only one assumption applies for any given configuration in a reactor plant). These assumptions are therefore consistent with NRR review practice of requiring licenseesto inalyze for any and all spurious actuations or failures where no two such spurious actuations or failures occur simultaneously " i tj g h b y l lt C. Conflicting Guidance, s E. d h ( ? ll l: i V h 70 / l lL -,<f ^ ',, f j.7 ', l. c f ii (d G% 1 u
~~r.,s s,~~
( f.', i] [fi [l( '9 \\\\ >" ~ p 1.- ',5l?;' f I l l 1 Rev.G 6/24/98 3-91
DRAFT BWROG Generic Guidance for Post Fire Safe ') l l Shutdown Circuit Analysis Assessment ,:d?, g.s;- lh ,- d - { )! fi t (... v. s y A ? A ~ 5 / [ H t,a 6 ..e' g [1 f, * ~ 'g [."{' " ~ * * * ..,Y. ji r 'Y )$# +sr =7' i p fi l> v I, t;h. J6;',T ly- {? t r' y; lw t.: h.,l i t l ~i.. - ~ r j f .f-L N' p ? 4 Rev.G 6/24/98 3-92 i
DRAFT BWROG - ( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.17 SPURIOUS ACTUATION OF SAFE SHUTDOWN EQUIPMENT A. Regulations Not specifically addressed in any regulation. A k, e t. ,[d p {,i B. Guidance i 1' y Generic Letter 85-01. Enclosure 6. Appendix R Questions and Answers, Section 3.8.4, Control Room Fire Considerations f. ... Note that the onif5sanual acti inth bholroonh evacuation usualiy[givederedit for'is the fiactor trip. i# prio ny additional mntrol fo6m actions dciemed necefisary dould have tokjustified under T the exemptlyn prcicess*.." p5j 6., p@ l % l [p
~~e. -~~
10 b., f (. Ge[eric Letter 88-10N: nclosure,2. Appendix R Questions and Answers, n a p w n Section 3.8.4. ControlRbom Fire Considerations ' Note that nly manual action in the control room prior to evach tion usually given credit for is the reactor trip. For any additional " control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided. Additionally, assurance would have'to be provided that such actions could not be negated by subsequent spurious actuation signals resulting from the postulated fire..." Generic Letter 86-10, Enclosure 2, Appendix R Questions and Answers. Section 5.3.1, Circuit Failure Modes. Also Generic Letter 85+01,. Appendix R Questions and Answers, Section 5.3.1, Circuit Failure Modes L QUESTION "What circuit failure modes must be considered in identifying circuits associated by spurious actuation?" f Rev.G 6/24/98 3-93 j
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment
~~RESPONSE~~
" Sections III.G.2 and III.L.7 of Appendix R define the circuit failure modes as hot shorts, open circuits, and shorts to ground. For consideration of spurious actuations, all possible functional failure states must be evaluated, that is, the component could be energized or de-energized by one or more of the above failure modes. Therefore, valve (dddld fail open or closed; pumps could fail running or not running: electrical distribution breakers could fail open or closed...." [ } N w y [I (( /7 L j p; Generic Letter 86-10,. Enclosure 2. AppenhxNQuestioins and Answers, Section 5.3.10. Design' Basis Plant Transients.1 Also Generic Letter 85-01,. Appendix R Questibns and Answers, Section 5.3.10. Design BasifPldnt Transients 8: l 7 (*,,9 ji l) tt g 4 h r,/ [j /P" ,J QUESTIOji if; y 4 g or dedicate'd shu"tdown(sigiild be considered in the design of the al , at plarjt transient
~~systems?"~~
~~tj j J.w RESPpNSE-If~~
~~er the criteria of Section III.L of Appendix R a loss of offsite power P~~
shall be assumed for a fire in any fire area concurrent with the following assumptions: a. - The safe shutdown capability should not be adversely affected by any one spurious actuation or signal resulting from a fire in any plant area; and b.- The safe shutdown capability should not be adversely affected by a fire in any plant area whicl results in the loss of all automatic function (signals, logic) from the circuits located in the area in conjunction with one worst case spurious actuation or signal resulting from the fire; and Rev,G 6/24/98 3-94 l L
I L i L(- j DRAFT BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment j l The safe shutdown capability should not be adversely affected by a j c. fire in any plant area which results in spurious actuation of the j l redundant valves in any one high-low pressure interface line." 'j l Mattson to Volimer Internal NRC Memo of 7/2/82. Position Statement en Allowable Repairs on the Appendix R RequirementforIime Requiredto ~ Achieve ColdShutdown gf: g k f i_ l Q "Section III.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage./;Thus, one train of systems needed for hot shutdown must be operable'during and following a fire. Operability of the h5t" shutdown /ysstems,,ihclu' ding the" ability to overcome a fire or fire suppressanlinduced rhaloperition of hot shutdown equipment and thOlaint's poIver distribution ' ysten$ must exist ki5out repairs. s Madual operationofialves, skitches and circuit breakers is allowed to opeEitte equ'hmedt'a@ isolat$ sysienui nfis not considered a repair. i i ~ ('... - HoWever, the rediovdl of fuses foiifolation is not permitted. All manual ? ophationsfiust%e achy 51e prior to the fire or fire suppressant induced maloperations maching an unrecoverable plant condition." p y N ,JVhitney to McKee InternalNRC Memo of8/11/86 Enclosure 2, SECY 85-306 Meeting Minutes of5/7/86 "It was noted that the three assumptions of Question and Answer 5.3.10 are meant for independent use (that is, only one assumption applies for any given configuration in a reactor plant). These assumptions are therefore consistent with NRR review practice of requiring licensees to analyze for any and all spurious actuations or failures where no two such spurious actuations or failures occur simultaneously." 1 L b Rev.G 6/24/98 3 95 t 2 _~
I
DRAFT BWROG .} Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment C. Conflicting Guidance Generic Letter 85-01, Endosure 6. Appendix R Questions and Answers, Section 3.8.4, Control Room Fire Considerations ... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. AnyIdditional control room actions deemed necessary would have td beljitstified under '}[f fl the exemption process..." b Generic Letter 86-10. Enclosure 2, Appendix R Questions and Answers, Section 3.8.4, Control Room Fire Considerations f A: s iis [,* ^ y "... Note that the o"nly manual acfion in thB con) trol room prior to avacu.,ation usuall/ given credit'fo,ris thefeactor tripvEdi'any additional ao .n a v congol roo~m actions 4eemed necessary pn.or to evacuation, a s be hrovided.$ Add [tli$ capabilit'y offperforming such a ) demonstration of actions coud noi.be riegatelby subsequent spurious actuation signals redultinglfr'om the pos'tuliEed fire..." E ):r 1 l i ) J Rev. G 6/24/98 3-96 i i l
[ DRAFT BWROG ~ -( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.18 LOSS OF OFFSITE POWER l A. Regulations 10 CFR SO, Appendix R. Section Ill.L Alternate andDedicatedShutdown Capability x. sp c c4S-I / i ...During the postfire shutdown, the reactor coola6t $$ stem process ] variables shall be maintained within those predicted for a' loss of normal a.c. power..." t /: N [ ki k l ...the altemate shutdown capability shall be iddepende6t of the specific j fire area (s) and shalliccommodate postfird conditions [vhere offsite power j is available and where offsite pdwh is ng available foPg2 hours. J Jroc6fures shall bie in sfrect toimplement this capability." Y Y b$ f1 ) "4.Jf'the capability td achieve anc main & 'n cold shutdown will not be tai ,( available becaush;of fire dadiagefth$ equipment and systems comprising th{means t'd achieve EidMsintain the hot standby or hot shutdown ) condition $ hall b'e,capalile of maintaining such conditions until cold i slMtdowdcandachieved. If such equipment and systems will not be chbl[bf being powered by both onsite and offsite electric power jystems because of fire damage, an independent onsite power system shall be provided. The number of operating shift personnel, exclusive of fire brigade members, required to operate such equipment and systems shall be on site at all times." "S. Equipment and systems comprising the means to achieve and maintain cold shutdown conditions shall not be damaged by fire; or the fire damage to such equipment and systems shall be limited so that the systems can be ] made operable and cold shutdown can be achieved within 72 hours. Materials for such repairs shall be readily available on site and procedures shall be effect to implement such repairs. If such equipment and systems used prior to 72 hours after the fire will not be capable of being powered by both onsite and offsite electric power systems because of fire damage, an independent onsite power system shall be provided. Equipment and l' systems used after 72 hours may be powered by offsite power only." j Rev.G 6/24/98 3-97
~ DRAFT BWROG' . Generic Guidance for Post-Fire Safe } Shutdown Circuit Analysis Assessment B. ' Guidance. Generic Letter 81-12. Enclosure 1. StaffPosition. Safe Shutdown Capability, Section 1 The design basis event for considering the need for alternative shutdown is a postulated fire in a specific fire area containing redundanTNfe shutdown cables / equipment in close proximity where it has been determined that fire protection means cannot assure that safe shutdown' capability will be preserved. Two cases should be consideredi (1) offsite power is available; and (2) offsite power is not available.! f j.o f;.A k N3 /f f f Generic Letter 86bo, Ficlosurd2,Yppendix R Questions and Answers, Section~5.3.6, On. Site Power. Also Generic Letter 85i01, Enclosure 6, Appendix R:Ouestions~andAnswers. Section 5.3.6. On-Site Power V V if h -f VM" /**' ') QUESTION 7 i x f N h AppendixR, Se[ction III.L.4 states in part, 'If such equipm w/ll not[ cap $ble of being powered by both on-site and off-site electrical ~ ~ gersystems because of fire damage, an independent on-site power p/ stem shall be provided.' Again, in Appendix R, Section III.L.5, the statement is made 'If such equipment and systems used prior to 72 hours after the fire will not be capable of being powered by both onsite and offsite electrical power systems because of fire damage, an independent onsite power system shall be provided.' An interpretation is needed of the meaning and the applicability of these two quotes relative to altemative shutdown capabilities.
~~RESPONSE~~
"These statements are meant to indicate that the alternative shutdown capability should be powered from an onsite power system independent (both electrically and physically) from the area under consideration. Further, if the normal emergency onsite power supplies (diesel generators) are not available because of fire damage, then a separate and independent onsite power system shall be provided. As an example, some plants are utilizing a dedicated onsite diesel generator or gas turbine to power ] Rev.G 6/24/98 3-98
DRAFT BWROG (. Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment. instrumentation and control panels which are a part of the alternative shutdown capability." C.- Conflicting Guidance . <d .e5 1 i 1 -s,ef k. rt I ?? N tt w c: h h f_' l t p j 'N h f / ,( h I'd./ C[1 /v t - +s: e-a ,y o,g.: s v[ !Q:.s. l'gf y fi n h is+ f:? .1 k .r.:- e Q Y p ..y g )+1J' d V/ jf t I i i Rev.G 6/24/98 3-99
DRAFT BWROG l Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment l sf , e,; ? r-c. ,,,..c,. e. e '. T' ( '; i a l-r 9-p s-1- t '- / g g %. lQ [d3 ([ t 1 r. v }. [ t+ { TT SY / ( (Y 5c,* g,f).~ j' I, J,i l;, / a. p.. l rlN# h: i-l \\ -. ~ L, t. .w I- .z. v, ) y '+ ~.p :: e A ? Rev.G 6/24/98 3-100 I
DRAFT BWROG ~ tij, Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.19 ALLOWABLE REPAIR BASIS A.
~~Regulations 10 CFR 50. Appendix R, Section 111.G.1.b. Fire Protection ofSafe Shutdown Capability~~
/ ,.-Gf " Systems necessary to achieve and maintain cold shutdown from either the control room or emergency control station (s) cany repaired within [ 72 hours." t hl f p r.+ r 10 CFR 50, Appendix $Section III.L5, Altir~ native andDedicated Shutdown Capability U; p e e it n h';- L L "Equipme%nt and ystems compninng the;6, b p fg e -n means to achieve and maintain cold shutdown canditions shall not be damaged by fire; or the fire damage ( to such equ$meft arid systeins silall 16 limited so that the systems can be ^ ma' e operable and cdid sl dtdown can be achieved within 72 hours. d Materials fdr such rep' airs }shall be readily available on site and procedur used prio,effect[iinplement such repairs. If such equipme sifall be r to 72 hours aRer the fire will not be capable of being powered
~~y b5th onsite and offsite electric power systems because of fire damage,~~
. li an independent onsite power system shall be provided. Equipment and systems used after 72 hours may be powered by offsite power only." B. Guidance Generic Letter 81-12. Enclosure 1, StaffPosition, Safe Shutdown Capability, Section 3.7 "The equipment and systems used to achieve and maintain cold shutdown conditions should be either free of fire damage or the fire damage to such systems should be limited such that repairs can be made and cold shutdown conditions achieved within 72 hours. Equipment and systems used prior to 72 hours aRet the fire should be capable of being powered by an onsite emergency power system; those used after 72 hours may be powered by offsite power." Rev.G 6/24/98 3-101
l DRAFT BWROG Generic Guidance for Post-Fire Safe } Shutdown Circuit Analysis Assessment I Generic Letter 81-12. Enclosure 1, StaffPosition. Safe Shutdown Capability, Section 8 "(f) Demonstrate that licensee procedure (s) have been developed which describe the tasks to be performed to effect the shutdown method. A summary of these procedures should be submitted. .6 (g) Demonstrate that spare fuses are available for control hiremts where these fuses may be required in supplying poder to' control circuits used for the shutdown method and may be blown by[ihe effects of a cable spreading room fire. The spare fuses should beJocated honvenient to the existing fuses. The shutdown procedure should informjhe operator to lp@ {} l check these fuses.Tf~T / 4. [' - dh) Deim nstrate tbt the manpower'requ$pd to performie shutdown functions uling th'epr6cedures of(f) as v'vell as to provide fire brigade mer$bers to fight tidfire is afailable qs# Eq'uired by the fire brigade i r technical "ifiditioliis. /# ) ff ~ f: ~~ (lkmor, ate'that repair procedures for cold shutdown systems are deYelope[andMterial for repairs is maintained on site." Mb Generic Letter 86-10, Enclosure 1, Interpretations ofAppendix R, Repair ofColdShutdown Equipment. Also Generic Letter 85-01, Enclosure 3, Interpretations ofAppendix R, Repair ofCold Shutdown Equipment "Section III.L.5 of Appendix R states that when in the altemative or dedicated shutdown mode, ' equipment and systems comprising the means to achieve and maintain cold shutdown conditions shall not be damaged by fire; or the fire damage to such equipment and systems shall be limited so that the systems can be made operable and cold shutdown can be achieved within 72 hours.' Section III.G.I.b contains the requirements for normal shutdown modes utilizing the control room or emergency control station (s) capabilities. The fire areas falling under the requirements ofIII.G.I.b are those for which an alternative or dedicated shutdown capability'is not being _ provided. For these fire areas, Section III.G.I.b requires only the Rev.G 6/24/98 3-102 l
___-_=._ DRAFT BWROG ~ .(. Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment capability to repair the systems necessary to achieve and maintain cold l shutdown from either the control room or emergency control station (s) within 72 hours, not the capability to repair and achieve cold shutdown within 72 hours as required for the alternative or dedicated shutdown j modes by Section III.L (noted above).
~~With regard to areas involving normal shutdown, howevef, tionI of i~~
Appendix R states that repairs must be made using only olisite capabilities. After repairs are made, cold shutdown can be achieved on'a reasonable schedule using any available powersource," ^ if h hl l? l Ni tf n SECY83-269. Attachin'Ent C. NR6StafPobitibns on PNst Fire Shutdown Capability, Allowdble Repairs tb Achieve ^ Safe Shutdoim, - g NL .R f J,)l [ f Section III.li of Appendix R states that repairs are permitted to provide the coldl<hutdoWn ca'pa$ility. AdditionallyESiction III.L indicates that ,(- prahedures kr tliese hairsinustMdeveloped and materials needed for the repairsjtored'on speM~ establish consistency in the plant designs, the - staffissued thefollowlfg guidelines conceming repairs. (memorandum R. h$sttso $ R.N611mer, dated July 2,1982) w V ,Section III.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage. Thus, one train of systems needed for safe shutdown has to be operable during and following the fire. Operability of the hot shutdown systems, including the ability to overcome a fire or fire suppressant induced maloperation of hot shutdown equipment and the plant's power distribution system, must exist without repairs. Manual operation of valves, switches and circuit breakers is allowed to l operate equipment and isolate systems and is not considered a repair. However, the removal of fuses for isolation is not permitted. All manual operations must be achievable prior to the fire or fire suppressant induced l maloperations reaching an unrecoverable plant condition. Modifications, e.g., wiring changes, are allowed to systems and/or components not used for hot shutdown, whose fire or fire suppressant induced maloperations may indirectly affect hot shutdown. These repairs must be achievable prior to the maloperations causing an unrecoverable ( plant condition. Rev.G 6/24/98 3-103 1 Y
DRAFT BWROG Generic Guidance for Post'-Fire Safe ) Shutdown Circuit Analysis Assessment Repairs for cold shutdown systems are allowed by Section Ill.L.5 of Appendix R. For cold shutdown capability repairs, the removal of fuses for isolation and the replacement of cabling is permitted. Also, selected equipment replacement, e.g., such as replacing a valve, pump, control room controls and instruments, will be reviewed on a case-by-case basis to verify its practicality within the appropriate time constraint,s. Procedures for repairing damaged equipment should be prepared in advance with replacement equipment (i.e., cables made-up with: terminal lugs attached) stored onsite. All repairs should be of suffici'ent quality to assure safe operation until the plant is restored to an operating condition. Repairs not permitted include the use of clip le. ads in control panels (which means the hard wired terminal lugs must be used), an'd the use ofjiunper cables other than those fastenediith terminaltlugs. [} f pp ie e s.. n . -Whenispairs are necessary in the. fire area, the licensee should reedfered add the%p'm taki$g plade'an demonstratiithat cient time is available to allow the area to be ix ected fire and firedtiipressant damage will not prevent thehpaffro ") endanger o ratnig sMearsPIn addition, written procedures must exist for thE orderl trangr ofUntrol from the control room and the remote shutdown stations and vice versa. The repairs to cold shutdown systems 2 are confdered to be an upper limit. The licensee may design the plant so Aat' cold shutdown can be achieved without repair. Mattson to Vollmer InternalNRC Memo of 7/2/82, Position Statement on Allowable Repairs on the Appendix R Requirementfor Time Required to Achieve ColdShutdown "Section III.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage. Thus, one train of systems needed for hot shutdown must be operable during and following a fire. Operability of the hot shutdown systems, including the ability to overcome a fire or fire suppressant induced maloperation of hot shutdown equipment i and the plant's power distribution system, must exist without repairs. Manual operation of valves, switches and circuit breakers is allowed to operate equipment and isolate systems and is not considered a repair. However, the removal of fuses for isolation is not permitted. All manual Rev.G 6/24/98 3-104 i l I L
DRAFT BWROG f ( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment operations must be achievable prior to the fire or fire suppressant induced maloperations reaching an unreco-erable plant condition." " Modifications, e.g., wiring change, are allowed to systems and/or components not used for hot shutdown, but whose fire or fire suppressant induced maloperations may indirectly affect hot shutdown., These repairs must be achievable prior to the maloperations causing an unrecoverable plant condition." fp p. "the removal of fuses for isolation and the replacement of cabling is permitted. Also, selected equipment replacement, e.g., s'uch as replacing a I valve, pump, control room controls and instrunients, will be reviewed on a ~ case-by-case basisIseiify its prMticality within the appropriate time constraints. Procedures for repaihrig damaged equipment should be -prepared in advance with replacement equipment (i. e,9a_bles made up withterminal lugbttIched) stored onsite.' All repairs should be of sufficient quality [Eipsure safe op'eratioriiintil the plant is restored to an (' operating condition. Repairi not. permitted included the use of clip leads in control panels (ivhichheadsthat hard wired terminal lugs must be used), ~ the use ofj perhIther than those fastened with terminal lugs." "WhenTepairs are necessary in the fire area, the licensee will have to ,dir$onstrate that sufficient time is available to allow the area to be re-entered and that expected fire and fire suppressant damage will not prevent the repair from taking place and that repair procedure will not endanger operating systems. In addition, written procedures must exist for the orderly transfer of control from the control room and the remote shutdown stations and vice versa. The repairs to cold shutdown systems are considered to be an upper limit. The licensee may design the plant so that 1 cold shutdown can be achieved without repair." C. Conflicting Guidance I l Rev.G 6/24/98 3-105 u
l DRAFT BWROG Generic Guidance for Post-Fire Safe ) ' Shutdown Circuit Analysis Assessment a-c .0 ;-. 'i [,[i + .w il N hl h [n IF.. f; r?'Y ['gn) X b p a p-c:
Y
~~~ .V ,w 4c;*'. c'y (; q p' % &p. s { }.;- s' ~ : h.{ f 1Y j p_ t*" ) e pt j 4 f. g- .gg J[msr 3 y~~
~~P J~~
Rev.G 6/24/98 3-106
DRAFT BWROG ~ i (~ ' Shutdown Circuit Analysis Assessment Generic Guidance for Post Fire Safe i 3.1.20 MANUAL OPERATOR ACTIONS A. Regulations 10 CFR 50. Appendix R. Section 1. Introduction andScope. Fire Damage l Limitsfor ColdShutdown ,p[*} "Both trains of equipment necessary to achieve co,1.d shutdown may be damaged by a single fire, including an exposure fiir, but damage must be limited so that at least one train can be repaired or made operable within 72 hours usmg onsite capability." i j; ,h I. h 9,Q h / 1 e e 10 CFR 50. Appendix R,;Section III.L4. Alternative andDedicated , Shutdown Capability j; j b, (; Y b hi. [f/
~~y "If the capability /td~hchieve a[nd maintain'c~old shutdown will not~~
'{ ava'ilable bhusfofye da%agejthe e'quipment and systems comprising the means to aclIieve and nisintain the hot standby or hot shutdown codition ih'all b$ caphie of maintaining such conditions until cold n sh'utdown# cart.b'e'Ichieved. If such equipment and systems will not be ~ cyable'of being powered by both onsite and offsite electric power systems because of fire damage, an independent onsite power system shall be provided. The number of operating shift personnel, exclusive of fire brigade members, required to operate such equipment and systems shall be on site at all times. B. Guidance Generic Letter 81-12 Enclosure 1, StaKPosition, Safe Shutdown Capability. Section 8 "(f) Demonstrate that licensee procedure (s) have been developed which describe the tasks to be performed to effect the shutdown method. A summary of these procedures should be submitted. l(- (h) Demonstrate that the manpower required to perform the shutdown functions using the procedures of(f) as well as to provide fire brigade Rev.G 6/24/98 3-107
I I DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment .mbers to fight the fire is available as required by the fire brigade technical specifications. Generic Letter 85-01. Enclosure 6. Appendix R Questions and Answers. Section 3.8..f. Control Room Fire Considerations 4.-.; ,,.f,f p; QUESTION pf ~~i. I t ...What actions can the operators take before evacuating the CR7..." L k i
~~RESPONSE~~
~~d. bi E V f ...The usual ass "Agtiof(sic)are [ fi .a y l 1 6 li- 'l. T.The ie' actor tripped in the ' ontroIroom. c~~
~~2. f~~
/ Y . b* 2 Offsitepopr 1 lost as well as atitomatic starting of the onsite a.c. g generatorspd k, e automafic function of valves and pumps whose _. ) control circuits c6uld be affected by a control room fire. l? lh Th'e anal sis s uld demonstrate that capability exists to manually achieve safcMiutdown conditions from outside the control room by restoring a.c. $wer to designated pumps, assuring that valve lineup is correct, and assuming that any malfunctions of valves that permit the loss of reactor coolant can be corrected before unrestorable conditions occur. Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Any additional control room actions deemed necessary would have to bejustified under the exemption { process..." Generic Letter 86-10. Enclosure 1, Interpretations ofAppendix R, Repair ofColdShutdown Equipment. Also Generic Letter 85-01, Enclosure 3, Interpretations ofAppendix R, Repair ofCold Shutdown Equipment "Section III.L.5 of Appendix R states that when in the attemative or dedicated shutdown mode, ' equipment and systems comprising the means to achieve and maintain cold shutdown conditions shall not be damaged j L Rev.G 6/24/98 3-108 1
DRAFT BWROG ( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment by fire; or the fire damage to such equipment and systems shall be limited so that the systems can be made operable and cold shutdown can be achieved within 72 hours.' Generic Letter 86-10. Enclosure 2, Appendix R Questions andAnswers. Section 3.8.4. Control Room Fire Considerations da L , gr y Id [h][b QUESTION .4 "...What actions can the operators take before evacuatirig the CR?... " k jr I ,g'Q,,. Ok j
~~RESPONSE~~
~~t = H b 2 6 J _ _f'...The:u'sual assumption (sic) rpm: j//' are~~
~~m u~~
~~g s 1. fThe r ppedin h ntroEcom. to y [ris; j yI as automatic starting of the onsite a '7~~
2.
~~Offsite po i~~
~~.we gene /ators$nd automatic function of valves and pumps whose 4~~
~~cont'rol ciEdiilts could be affected by a control room fire.~~
p/ 1malysis should demonstrate that capability exists to manually achieve safe shutdown conditions from outside the control room by restoring a.c. power to designated pumps, assuring that valve lineup is correct, and assuming that any malfunctions of valves that permit the loss of reactor coolant can be corrected before unrestorable conditions occur. Note that the only manual action in the control room prior to evacuation l-usually given credit for is the reactor trip. For any additional control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided. Additionally, assurance would have to be provided that such actions could not be negated by subsequent spurious actuation signals resulting from the postulated fire." Rev.G 6/24/98 3-109
DRAFT BWROG Generic Guidance for Post-Fire Safe } Shutdown Circuit Analysis Assessment Mattson to l'ollmer InternalNRC Memo of 7/2/82, Position Statement on Allowable Repairs on the Appendix R Requirementfor Time Required to Achieve ColdShutdown "Section III.G.1 of Appendix R states that one train of systems needed for hot shutdown must be free of fire damage. Thus, one train of systems needed for hot shutdown must be operable during and follswlng a fire. Operability of the hot shutdown systems, including the ability to overcome a fire or fire suppressant induced maloperatio'n of hot shutdown equipment and the plant's power distribution system, must exist witliout repairs. Manual operation of valves, switches and circuit breakeN is allowed to operate equipment and isolate systems and is not considered a repair. However, the remfaljf. fuses for' isolation is hot perm'itted. All manual operatio.ns must beschi,epable pridt to the^ fire or fire s,uppressant induced mnaloperations reaching an unre'coverable' plant conditio'n." r. C. Conflicting Guidance ) (. f a Generic Letter 85-01, ' nclosure 6, Appendix R Ovestions and Answers, E Shetion 3?8.44'bntrol Room Fire Considerations do e that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Any additional control room actions deemed necessary would have to be justified under the exemption process..." Generic Letter 86-10. Enclosure 2 Appendix R Questions and Answers, Section 3.8.4. ControlRoom Fire Considerations ... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. For any additional control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided. Additionally, assurance would have to be provided that mch actions could not be negated by suWequent spurious actuation signals resulting from the postulated fire..." Rev. G 6/24/98 3-110
DRAFT BWROG t Generic Guidance for Post-Fire Safe s Shutdown Circuit Analysis Assessment 3.1.21 EMERGENCY LIGHTING A. Regulations 10 CFR 50, Appendix R, Section 111.J, Emergency Lighting Emergency lighting units with at least an 8-hour battery powhsupply shall be provided in all areas needed for operation of safe shutdown equipment and in access and egress routes there' to.j ! [ ,y fn. e l_ f-f: 2 k B. Guidance ip ify't j d% NUREG-0800, SRP, Section 9.Sl1,1 Fire Protection Prog; ram. Se C.5.g. Lighting and Communication g y' b q p,4 /(' r? Lighting an'd twgWay voicefomrhuniedtion are vital to safe shutdown md u (' emergency response in the pent offire. Suitable fixed and portable emergency, lighting and communication devices should be provided as s h I M fo ows: 5 ll" k; (f) Fixed self-contained lighting consisting of fluorescent or sealed-beam
~~,pti^ nits with individual 8-hour minimum battery power supplies should I~~
be provided in areas that must be manned for safe shutdown and for access and egress routes to and from all fire areas. Safe shutdown areas include those required to be manned if the control room must be evacuated. (2) Suitable sealed-beam battery-powered ponable hand lights should be provided for emergency use by the fire brigade and other operations personnel required to achieve safe plant shutdown. i Rev.G 6/24/98 3-111 1
l l 1 DRAFT BWROG l Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment 1 Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers, Section.4. Emergency Lighting. Illumination Levels Question 4.1 Also l Generic Letter 85-01, Enclosure 6. Appendix R Questions and Answers, Section.4, Emergency Lighting. Illumination Levels Question 4.1 ) QUESTION 6-s l What is the requisite intensity level for emerggncy liglitin ad ' egressroutes and areas where shutdown functions must lie performed? l What are the bases for determining these levels oflighting? I 0 U l t YA 0 f.. y ll). j.V:1 l{.
~~RESPONSE~~
.~ g r. o The level.ofillumination provi d.by eme,rgency lighting in access routes -to,ana'ikideas where shutdown,.fSnctiors must be performed is a level thatis sufficient to criable an6perator tdreach that area and perfonn the shutdodd fuEEtions. At die reEnoteihiltdown panels the illumination .), ~7 r cp6tfol' panel operators. le Is shou beiuf en Tlie bases r e "mati g these levels oflighting are the guidelines co'ntaine[in S$clion 9,5.3 of the Standard Review Plan, which are based oh'indus'try standards (i.e., Illuminating Engineering Society Handbook). ? Where a licensee has provided emergency lighting per Section III.J Appendix R, we would expect that the licensee verify by field testing that this lighting is adequate to perform the intended tasks. C. Conflicting Guidance Rev.G 6/24/98 3-112
DRAFT BWROG 'i Generic Guidance for Post-Fire Safe Shutdown Circuit Aralysis Assessment 3.1.22 EXEMPTIONS A. Regulations 10 CFR 50.12, Specific Exemptions ./: (a) The Commission may, upon application by any interesied person or upon its own initiative, grant exemptions from thetequirements of the regulations of this part, which are--' ef*
~~p (1) Authorized by law, will not present animdue Hs/~~
k to the public health and safety, and are consistent with the common.defenseand security. (2) The Commission will not con' sider gr$nting an exemption unless special circumstances are present'Special circsmstaneg are present whenever-jf f /k h' g - (i) Application of the regulation in the particular circumstances conflicts L with other rsies d.~reqEiremeniforthe CIommission; or (iifApplicidion ' fib regulation!in the#particular circumstances would l {- not serve thun [ly'ing pudx>se,5f the rule or is not necessary to achieve thejunderlymg ppse of he rule; or. ~ iii) Compliance would result in undue hardship or other costs that are significantly imbTcess of those contemplated when the regulation was apoged','or that are significantly in excess of those incurred by others { sumlarly situated; or j " (iv) The exemption would result in benefit to the public health and safety that compensates for any decrease in safety that may result from the grant of the exemption; or (v) The exemption would provide only temporary relief from the , applicable regulation and the licensee or applicant has made good faith efforts to comply with the regulation; or (vi) There is present any other material circumstance not considered when the regulation was adopted for which it would be in the public interest to grant an exemption. If such condition is relied on exclusively - for satisfying paragraph (a)(2) of this section, the exemption may not be granted until the Executive Director for Operations has consulted with the Commission. (b) Any person may request an exemption permitting the conduct of t-activities prior to the issuance of a construction permit prohibited by Sec. 50.10_. The Commission may grant such an exemption upon considering and balancing the following factors: Rev,G 6/24/98 3-113
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment (1) Whether conduct of the proposed activities will give rise to a significant adverse impact on the environment and the nature and extent of such impact,if any; (2) Whether redress of any adverse environment impact from conduct of the proposed activities can reasonably be effected should such redress be necessary; g (3) Whether conduct of the proposed activities would foieclo'se subsequent adoption of alternatives; and f VyI (4) The effect of delay in conducting suchstivities on the public interest, including the power needs to be used by the proposed facility, the availability of alternative sources, jf any, to' meet those needs on a timely basis and delay costs to the applicant and to.cohsumers!! Issuance of such ati'hx'emption sh'all not be dee'med to constitute a commitment to issu' e a construefioit permit. During theteriod of any thi5 _;xemptioh granted pursuant tofshall be cahied ont in such a diEnn p er as will minimize or reduce their environmentalinspaht. / ?,/0" ~^ ? b. ) a p b B. Gidancqf (T',- y 4 ene c' Letter 85-01. Enclosure 6. Appendix R Questions and Answers, fection 3.8.4, Control Room Fire Considerations
~~RESPONSE~~
... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Any additional control room actions deemed necessary would have to be justified under the exemption process..." Generic Letter 86-10, Enclosure 1, Interpretations ofAppendix R, Jtem 3 Fire Damage. Also Generic Letter 85-01, Enclosure 3, Interpretations of l Appendix R. Item 3, Fire Damage " Appendix R to 10 CFR Part 50 utilizes the term ' free of fire damage.' In promulgating Appendix R, the Commission has provided methods acceptable for assuring that necessary structures, systems and components Rev.G 6/24/98 3-114 l 1 l L____
DRAFT BWROG ( Generic Guidance for Post Fire Safe Shutdown Circuit Analysis Assessment t are free of fire damage (see Section Ill.G.2a, b and c), that is, the structure, l system or component under consideration is capable of performing its intended function during and after the postulated fire, as needed. Licensees seeking exemptions from Section Ill.G.2 must show that the l altemative proposed provides reasonable assurance that this criterion is met. (Note also that Section III.G.2 applies only to equipmentmeeded for hot shutdown. Therefore, an exemption from Ill.G.2 foriold shutdown equipment is not needed.)"
~~l' f f~~
..a ' ^ y ? Y Generic Letter 86-10. Enclosure ilinterpretations ofAppendix R. Item 5, Automatic Suppression and Detection. Also Generic Letter 85-01,, Interpretations ofAppendix R. Item 5, Automatic Suppression andDetection /[ f lL n .(? "y g f. ,7 Sections III.G.2.bcand 1II.G.2.Fof) Appendix R state that "In addition, fire detectors an'd autEmAtic fire s'upp/piendix R also use ( fire' area...'[Othdr'prEvisions of ~ dehetors arid an auto %atiEfire suppression system in the fire area..." (see e.g., Sectibn III.G.2.e).' p j.s' l In7 order to comply with these provisions, suppression and detection , sufficient to protect against the hazards of the area must be installed. In this regard, detection and suppression providing less than full area coverage may be adequate to comply with the regulation. Where full area suppression and detection is not installed, licensees must perform an evaluation to assess the adequacy of partial suppression and detection to protect against the hazards in the area. The evaluation must be performed by a fire protection engineer and, if required, a systems engineer. Although not required, licensees may submit their evaluations to the staff for review and concurrence. In any event, the evaluations must be retained for subsequent NRC audits. Where a licensee is providing no suppression or detection, and exemption must be requested. i l-Rev.G 6/24/98 3-115
DRAFT BWROG Generic Guidance for Post-Fire Safe } Shutdown Circuit Analysis Assessment Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers. Section 2. Overview. Also Generic Letter 85-01. Enclosure 6. Appendix R Questions and Answers. Section 2. Overview Section 50.48 also requires that all plants with operating licenses prior to January 1,1979 satisfy the requirements of Section 111. 6,1113 and Ill.0, and other Sections of Appendix R where approval of similar features had not been obtained prior to the effective date of Appendix R. By a separate action, the Commission approved the staffs requirement that all plants to receive their operating license afterdanuary 1,1979 also' satisfy the requirements of Sections III.G, IILJ and III.O and that i fire protection license condition. bfestablished/deviatioris~ from Apl endix R i requirements for pje-19.79 plants" are proEessed under ilie exemption process.~ Deviation from others#uiEelines are identifted~dnd eva the Safety Evaluati,on-Report. ! ,k y v[% i y b 5 , fe p i: ) Gederic Letter 86-10.\\ Enclosure 2, Appendix R Questions and Answers. Section 3.8.4. Control' Room Fire Considerations p. j ), - RESPANSE ... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. For any additional control room actions deemed necessary prior to evacuation, a demonstration of the capability of performing such actions would have to be provided. Additionally, assurance would have to be provided that such actions could not be negated by subsequent spurious actuation signals resulting from the postulated fire..." i Rev. G 6/24/98 3-116
. DRAFT BWROG f( Generic Guidance for Post-Fire Safe
~~Shutdown Circuit Analysis Assessment Generic Letter 86-10, Enclosure 2. Appendix R Ouestions and Answers.~~
V Licensing Policy. Section 8.3,111.G. J and O Exemptionsfor Future Modifications. Also Generic Letter 85-01, Enclosure 6, Appendix R Questions and Answers. Licensing Policy, Section 8.3.111.G. J and O Exemptionsfor Future Modifications / f, (fi QUESTION x.Ae. Is an exemption required from Appendix R' Sections o; ther than III.G, III.Jand III.O for future modifications thatfdo not compip with such i-sections? j . / g-m l t f ]A
~~RESPONSE~~
M,
/N F ff u P lnF %fp Yestfo%Fplants liebvsed prior to' January f:;: 1979 and/or those modifications which' deviate from the previously accepted fire protection configuratidss. Thihxclusio' of the applicability of Sections of n (.. Appendix Rbthdr th5n III.G', Illa a'nd III.O is limited to those features "acceptdd byMC staff as satisfying the provisions of pendixA to BrancifTechnical Position BTP APCSB 9.5-1 reflected in Ap"ff firefrotec'tfo'n safety evaluation reports issued prio sta effegtive date of the rule." No reanalysis is required except for poposed modifications which would alter previously approved features. This position is based directly on CFR 50.48(b). Also see response to Question 8.1. Generic Letter 86-10, Enclosure 2, Appendix R Questions andAnswers, Licensing Policy, Section 8.4, Future Changes. Also Generic Letter 85-01, Enclosure 6. Appendix R Questions andAnswers, Licensing Policy, Section 8.4,- Future Changes QUESTION . Will future changes (no matter how minor) to approved configurations be required to be reviewed by the Staffin an exemption request? At what point may the process of 10 CFR 50.59 be invoked? Rev.G 6/24/98 3-117
l 1 l DRAFT BWROG Generic Guidance for Post-Fire Safe ) l Shutdown Circuit Analysis Assessment
~~RESPONSE~~
If a future modification involves a change to a license condition or technical specification, a license amendment request must be submitted. When a modification not involving a technical specification or license condition is planned, the evaluation made in conformance with 10 CFR 50.59 to determine whether an unreviewed safety questioIis' involved must include an assessment of the modification's im;iact En th'e existing fire hazards analysis for the area. This part;6f the evaluation must be performed by the person responsible for th6 fire safety t rogram for the i plant. The assessment must include'the effect ori combustible loading and distribution and the consideration %f whether circuits ohcomponents, including associat6fciircuits, foritrain of$q~uipment n'e'eded for safe shutdoyn are bein5 aff5cted or a'nEw ele whiseval6ation co6cludes that therelis nod, Ment introdu ignificantimpact, this conclusion and its basis mustpe ' documented as part of the 50.59 evalisation had bEahilable for fu'urejnsjiection and reference. If the _) f evaluation finds /that\\therep an,iin;Iact that could result in the area either noflbeing i$ conform $dcemith Appendix R, or some other aspect of the rotection program, or being outside the basis for an approved fire p% granted for the area involved, the licensee must exempticdi that riakedodifications to achieve conformance orjustify and request jxefn~ption (or, for the post 1979 plants, approval) from the NRC. See also responses to Questions 8.1 and 8.2. Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers, Licensing Policy, Section'8.6, Trivial Deviations. Also Generic Letter 85-01, Enclosure 6, Appendix R Questions andAnswers, Licensing Poliev, Section 8.6, TrivialDeviations QUESTION What guidance can the NRC Staff give the industry regarding when a deviation from the literal interpretation of Appendix R is sufficiently trivial as to not require a specific exemption? Rev.G 6/24/98 3-118
_ _ _ = - _ _ _ _ _ _ - _ _ - _ - - - l DRAFT BWROG ~ . (' Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 4
~~RESPONSE~~
The significance of a deviation must be judged as part of a fire hazards j analysis. The conclusion of this analysis is always subject to review by 1 the NRCinspector. df 1 4f l i i Generic Letter 86-10. Enclosure 2. Appendix R. Questions andAnswers, Licensing Policy, Section 8.8, Smallest Opening in a FirsBarrier. Also i Generic Letter 85-01, Enclosure 6, Appendix R Questions and Answers, Licensing Policy, Section 8.8, Smallest Openindin a Fire Barrier p,9 QUESTION yh h, ((9 (}y,' w s c.' Y r: .p V.
~~_ Whatis the smallest opening allowed in a fire area barner for which an exemption requestismot needed? <~~
L{. h h~ . f'". /;J: i RESPONSE ~ c p.y f e Unsealedppenirds in e configuration for which approval was obtained by a rovediaboratory or the NRC staff would be acceptable. position on openings is given in Section 5.a(3) of BTP CMEB 9.5-1: "(3) Openings through fire barriers for pipe, conduit, and cable trays which separate fire areas should be sealed or closed to provide a fire resistance rating at least equal to that required of the barrier Itself. l Openings inside conduit larger than 4 inches in diameter should be sealed at the fire barrier penetration. Openings inside conduit 4 inches or less in diameter should be sealed on each side of the fire barrier and sealed J either at both ends or at the fire barrier with non-combustible material ] L to prevent the passage of smoke and hot gases. Fire banier penetrations j l that must maintain environmental isolation or pressure differentials L should be qualified by test to maintain the barrier integrity under such conditions." The unsealed opening (s) allowed in a fire area boundary or a barrier which separates redundant shutdown divisions should not permit flame, radiant energy, smoke and hot gases to pass through the barrier and cause damage l Rev.G 6/24/98 3-119
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment i to redundant shutdown divisions on the other side. The licensee should assess the adequacy of existing protection and should determine the minimum size based on a fire hazards analysis and conservative fire protection engineering judgment. If the significance of openings in fire barriers is marginal, a formal exemption request could be submitted or the staff consulted. The basis for the lack of significance should be availtble for review by NRC Inspectors. g q."i Our acceptance of unprotected openings in file'g V [ bairie~ s pould depend r upon the quantity and nature of combustible materials on either side of the barrier; the location of the opening (s) in relation to the ceiling (for openings in walls); the location, vulnerability;ind importance of shutdown systems'o'n'either side'o'f the bdNier) and coidpensating fire protection. h h; ff( h pl( Mee also Section #4 offhe "Interpmtatiorp of Appendix'R." y yi $.b2 V F M i 6 l% F7 Generic Letter 86-10lEncloslure2 Appendix R Ouestions a Licensing Policp; Section B.9, NFPA Code Deviation. Also Generic Letter ) ~ 85-01, Enclosure 6, Appendix R Questions and Answers, Licensing Policy, Section 8.9, NFPA Code Deviation g) , QUESTION Is an exemption / deviation required for deviations from NFPA Codes?
~~RESPONSE~~
Deviations from the codes should be identified and justified in the FSAR or FHA. An exemption is not required for NFPA codes. NRC guidelines reference certain NFPA codes as guidelines to the systems acceptable to the staff, and therefore such codes may be accorded the same status as Regulatory Guides. When the applicant / licensee states that its design " meets the NFPA codes" or, " meets the Intent of the NFPA Codes" and does not identify any . deviations from such codes, NRR and the Regions expect that the design conforms to the code and the design is subject to inspection against the NFPA codes. ] Rev.G 6/24/98 3-120
l l l l DRAFT BWROG ~ !( Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment ) Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers. l Licensing Policy. Section 8.9. " ASTM E-119" Design Basis. Also Generic Letter 85-01. Enclosure 6. Appendix R Questions and Answers. Licensing I Poliev Section 8.9. "ASTME-119" Design Basis j QUESTION f.d.?c I i Is an exemption / deviation required, if components are designed to withstand an " ASTM E-119" fire? (" ' }! f i W ff' gg>j f /p
~~RESPONSE~~
Some cables are beIg developed'for high1emkrature(p c ? I e.g.,1700 F) applications. An c!xemhon wo61d be required if suchfca,ble is used in lieu ortlie) alternatives ofIII.G:2.or III.0:3 in a pre-1979 plant. A devi.stion from the,gtiidelines would beiequired for similar applications in a' post 19k9 plantf / ,jh'~ l{'
(
l f g,: lie l 'L \\ tg { l G5n,eric Litter 86-10, inclosure 2. Appendiz R Ouestions andAnswers, Licensing Policy Section 8.14, Deviation From Guidance Documents. Also, Generic Letter 85-01, Enclosure 6, Appendix R Ouestions and l ,,enswers, Licensing Polley, Section 8.14, Deviation From Guidance Documents QUESTION ) If a utility determines that'a deviation from a guidance document exists, does an exemption request need to be filed? If so, what is the legal basis forthis requirement?
~~RESPONSE~~
No. L Rev.G 6/24/98 3-121 l l i i
\\ 1 DRAFT BWROG Generic Guidance for Post Fire Safe } Shutdown Circuit Analysis Assessment Generic Letter 86-10. Enclosure 2. Appendix R Questions and Answers. Licensing Policy, Section 8.19, Exemption Request Threshold Also Generic Letter 85-01, Enclosure 6. Appendix R Questions and Answers, Licensing Poliev, Section 8.19, Exemption Request Threshold QUESTION ,.p --- ,~r (a) What is the threshold for exemption requests?_(b)Is it necessary to file a request for each and every possible.deVlation from' Appendix R? If h l j h.j h I
~~RESPONSE~~
Typical examples 4Iridiscussed iii the reshnse to Ques (tion e Hf Y through 8.19.4. h El /h pr h l f; h }.k p r (a) The licensee rnust develop'its criteria for an exemption request threshold. i .p- ,t.i 7~ 1 p ,.M* j h , W, ~) l i l.,l s/ (b)'No. g v h Generic $etter'86-10, Enclosure 2. Appendix R Questions andAnswers, Liicensing Poliev, Section 8.19.1, Penetration Designs Not Laboratory )piiroved. Also Generic Letter 85-01. Enclosure 6, Appendix R Questions and Answers, Licensing Policy, Section 8.19.1, Penetration Designs Not LaboratorvApproved i QUESTION Where penetration designs have been reviewed and approved by NRC but have not been classified by an approval laboratory, will it be necessary to submit an exemption request?
~~RESPONSE~~
No. J Rev.G 6/24/98 3-122
l l-DRAFT BWROG '(" - Generic Guidance for Post-Fire Safe - Shutdown Circuit Analysis Assessment Generic Letter 86-10, Enclosure 2 Appendix R Ouestions andAnswers, ' Licensing Policy. Section 8.19.2. Individual vs. Package Exemptions. Also Generic Letter 85-01, Enclosure 6 Appendix R Questions and Answers, Licensing Policy Section 8.19.2, Individual vs. Package Exemptions QUESTION
~~.~. !~~
~~.;_c How do we submit future modification exemption ifeguesIs, etc.? Would NRC prefer them individually, or developed'and sybinittes in packages for ~ [l review and approval? g w i a l .G [ g' /~~
~~RESPONSE~~
/n .s 97~ih /M P J JE f Future exemptiond should be suliditted individually, ifihey are a! --inde[d'eint of ea'ch o,ther. /J fj d L. /~ l Generic Letter 86-10lEncidsure22:2ppendix R Ouestions and Answers, \\ Libensing Polici;iSection Bi19.3, Exemption Request Supporting Detail. Also Gen &lc Letter 85-01, Enclosure 6. Appendix R Questions and Answers,*Licessing Policy, Section 8.19.3, Exemption Request Supporting Detail # y QUESTION When an exemption request is filed, what criteria are used to determine the level of detail needed to support the request?
~~RESPONSE~~
See Enclosure 2 ofNRC's letter to all licensees dated April-May 1982. l . Rev. G 6/24/98 3-123
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment ] l Generic Letter 86-10. Enclosure 2, Appendix R Questions and Answers, Licensing Policy, Section 8.19.4, 50.12 vs. 50.48 Exemption Requests. Also Generic Letter 85-01, Enclosure 6. Appendix R Questions and Answers. Licensing Policy. Section 8.19.3, 50.12 vs. 50.48 Exemption Requests QUESTION fr# "i di f f? With regard to exemption requests for future modifications, will they be submitted under 50.12 or 50.48? (i fr;j } l; c p$ fj
~~RESPONSE~~
~~y, cy p / 8 d 10 CFR. S_D 12. U -R~~
~~.i 4'"~'Q_~~
l y ( F n Is t' u b. Generic Leiter 86-10, Enclosure 2, Appen_ dix R Questions and Answers, Licensing Policy;$ection 820. Bost' January 1,1979 Plants and ) Exemption!Reqdests. Miso! Generic Letter 85-01, Enclosure 6 Appendix R Osestions'and Answefs, Licensing Policy. Section 8.20, Post January 1, 1979 Plants aridExemption Requests ?) ,, QUESTION Do plants licensed after January 1,1979 which have committed to meet the requirements of Section III.G, III.J and III.O and are required to do so as a license condition, need to request exemptions for alternative configurations?
~~RESPONSE~~
No; however, deviations from the requirements of Section III.G, III.J and III.O should be identified and justified in the FSAR or FHA and the deviation would probably require a license amendment to change the license condition. See responses 8.1 and 8.2. ) Rev.G 6/24/98 3-124
I DRAFT BWROG 7 ( ' Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment i Rubenstein to Mattson, InternalNRC Memo of12B/82, Use ofAutomatic Depressuri:ation System (ADS) aaJ Low Pressure Coolant injection (LPCI) to Meet Appendix R, Alternate Shutdown Goals In the course of performing Appendix R, safe shutdown reviews, the Audliary Systems Branch has noted that various boiling water reactor; facilities propase the use of ADS in conjunction with LPCI as their propod alternate shu:down method in order to achieve and maintain safe shutdpwh foiicwing a fhe event in certain portions of the plant. For some cases this s'trategy will result in a shon-term uncovering of the upper ponion 'of the c' ore ddring depressurization. tM v befdence gihe results which Analyses of similar events discus in th indicate that the uriEvb time is'slion en8iigh'and thejunount of fuel uncovered is smal[enough, that/ cladding; integrity wodid,not be -threateried.;The " lettered" requirements of Appendix.R;however, would not be satisf.ied sin.ce, Section III.L.statess s u -- m 3, {
~~l. "k...During thepostSre sh dow', the reactor coolant system process n~~
~~ariableishell be hintained within those predicted for a loss of hiormal'ACho,wer.Y..$ and f f 2f "Th'e reactor coolant makeup function shall be capable of maintaining~~
~~he reactor coolant level above the top of the core for BWRs..."~~
,,/ t The use of ADS and LPCI would not be the preferred means of maintaining reactor core cooling. Nevertheless, the use of ADS and LPCI is an approved and accepted means ofachieving and maintaining safe shutdown conditions, and does comply with certain provisions of Section ] III.L of Appendix R regarding fission Product boundary integrity. 1 Based on the above, for those licensees who have proposed the use of ADS and LPCI for attemate shutdown in the event of a fire, we consider their proposal as a request for an exemption to the requirements of the above referenced ponion to Section III.L of Appendix R, and intend to ) grant such exemptions. ) 1 Rev.G 6/24/98 3-125 l
) DRAFT BWROG ~ l , Generic Guidance for Post-Fire Safe )! Shutdown Circuit Analysis Assessment r t C. Connicting Guidance Generic Letter 85-01. Enclosure 6. Appendix R Ouestions and Answers, . Section 3.8.4, Control Room Fire Considerations "... Note that the only manual action in the control room prior to evacuation usually given credit for is the reactor trip. Anyadditional control roem actions deemed necessary would have to%ju.etified under the exemption process..." g#"'f [ j 57 p / ff Generic Letter 86-10. Enclosure 2,' Appendix R'Questiofis and Answers, Section 3.8.4, Control Room Fire Considerations t "..Notethat the ly. ual ac i in t control ro prior to eva'c5 tion"dsuall[gjv$n credit fofjs theIcactor tripIFor any additional confiol rooln'acti5ns deemed 'nece'sharyjrior to evacuation, a denin'o'nstrati6n of'ihehpability o[perfirming such actions would have to ~' bekovided.S AcNitioylly/assur~ance would have to be provided that such actions codd ndi be noin(c'd by subsequent spurious actuation signals resulting / rom,hstulated fire..." b j, J . Rev. G ' 6/24/98 3-126
DRAFT BWROG 'b Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 3.1.23 SUPPRESSION AND DETECTION A. Regulations 10 CFR 50. Appendix R. Section ll.C. Fire Protection Features ./ "3. Fire detection systems, portable extinguishers, and staddpipe and hose stations shall be installed. AIO i
~~4. Fire barriers or automade suppression.systen'ii6r.both'shall be installed as necessary to protect redundant systems or compon'entinecessary for safe shutdown...~~
~~[ [ f~~
~~6. Fire detection and,suppressionsystemslshall be designed, installed, maintained, and tested by personn(1 properly q'ualified by experience and training in fire protection systems.N g,~~
p ,fQ ld 9 lV f.;. /? fyd"/ -y u g 10 CFR 50. AppindliR. Sect (ion Ill. Specific Requirements j ti C ' fr f \\ f l j:. f } JF l "4;Wate 1 be, lies fordire. suppression systems. Two separa pp suplies todhe fire,ma, lo,op..." p {f y 10 CFR 50. Appendix R. Section Ill.G, Fire Protection ofSafe Shutdown Capability "2. Except as provided for in paragraph G.3 of this section, where cables or equipment, including associated non. safety circuits that could prevent operation or cause maloperation due to hot shorts, open circuits, or shorts to ground, of redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located within the same fire area outside of primary containment, one of the following means of ensuring that one of the redundant trains is free of fire damage shall be provided: a. Separation of cables and equipment and associated non-safety circuits of redundant trains by a fire banier heving a 3-hour rating. Structural steel forming a part of or supporting such fire <C Rev.G 6/24/98 3-127
l DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment barriers shall be protected to provide fire resistance equivalent to that required of the barrier; b. Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustible or fire hazards. In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area; ot,.#f i ,A Y f I Enclosure of cable and equipment'and ss' ciated non-safety c. o circuits of one redundant train inia fire barrier'having a 1-hour rating,- In addition, fire Eletectori and an autgYnatic fire suppression system shall be installed in the five area; y"y pj [f } [ Inside pninerted containments one of the Grejrotection m - 9., ^dneansppecified abovelor one'of the following fire protection means'shall be provid'ed: if. i' Separ(ation)of cables andiquipment and associ Yi V / fi JW f. d. ) /circuNs ofhu$ dant trains by a horizontal distance of more 7) hanS0 feet Gith no intervening combustibles or fire hazards; y p; Installation of fire detectors and an automatic fire suppression system in the fire area; or f. Separation of cables and equipment and associated non-safety circuits ofredundant trains by a noncombustible radiant energy shield. 3. Altemative or dedicated shutdown capability and its associated circuits, independent of cables, systems or components in the area, room or zone under consideration, shall be provided: Where the protection of systems whose function is required for a. hot shutdown does not satisfy the requirement ofparagraph G.2 of this section; or b. Where redundant trains of systems required for hot shutdown located in the same fire area may be subject io damage from ~ ..J Rev.G 6/24/98 3-128
DRAFT BWROG / Generic Guidance for Post-Fire Safe \\ Shutdown Circuit Analysis Assessment fire suppression activities or from the rupture or inadvertent operation of fire suppression systems. In addition, fire detection and a fixed fire suppression system shall be installed in the area, room, or zone under consideration." ,/ ,pr:% B. Guidance Ih-e' \\? NUREG-0800, SRP, Section 9.5.1, Section A. Introduction n ( l U " General Design Criterion 3, " Fire:Protecdon," of Appendix A, " General Design Cruria for Nuclear Power! Plants," to 1.0 CFR Part 50, " Licensing of Production andptilization Fac@ies/ hquiles that jtructures, systems, and cor6po"nents ip'er/afety requirements,'the probabilit portant to safeiy be designed an416 cited to minimize, consistent ivith oth fires and ex' losionsiNoncombustible and-heat-resistant materials are p required to pe us ~ ( locations sdcih as.the contam,ef practical throughout the unit, part erev L ment and control room. Criterion 3 also requires t%t firf detec' tion and suppression systems of appropriate capacity,and gapiibility be provided and designed to minimize the adverse effect of fires on structures, systems, and components important to safety ,a'nd that firefighting systems be designed to ensure that their failure, rupture or inadvertent operation does not significantly impair the safety capability of these structures, systems, and components. NUREG-0800 SRP, Section 9.5.1, Section C1.b, Fire Ha:ards Analysis i "The fire hazards analysis should separately identify hazards and provide appropriate protection in locations where safety-related losses can occur as i a result of: l (8) Inadvertent operation of fire suppression systems." l NUREG-0800. SRP, Section 9.5.1, Section C1.c. Fire Suppression System Design Basis "(1) Total reliance should not be placed on a single fire suppression j system. Appropriate backup fire suppression capability'should be i provided. I Rev.G 6/24/98 3-129 l 1 J
1 I l I }) DRAFT BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment (2) A single active failure or a crack in a moderate-energy line (pipe) in the fire suppression system should not impair both the primary and backup fire suppression capability. For example, neither the failure of a fire pump, its power supply or controis, nor a crack in a moderate-energy line in the fire suppression system, should result in loss of function of both sprinkler and hose standpipe systems in an area protected by such primary and backup systems. gCl (3) As a minimum, the fire suppression system should bei:apable of delivering water to manual hose stations locate'd within hbse reach of areas containing equipment required for safe plant shutdown following the safe shutdown earthquake (SSE). In areas of high seismic activity, the staff will consider on a case-by-case basis the need to design the fire detection and suppression systenfs~to'be functio'rkl folloWindthe SSE.' (4) The fire protection s'y' stems shoilld retain their original design ~ ~ -capabilit'y'for (a) natural phenoineria ofless severityand' greater frequency thari the most sevne riatural phehomena[(approximately once in 10 years) such* as torn'adoesSiirricaned flodds, icEstorms, or small-intensity earthquakes thatlare characteristic'8f'the geographic region, and (b) ) pothntial n/an-m'ade site-tdlated events such as oil barge collisions or ai/ craft crShesIhat haYe~a reasonable probability of occurring at a specific pl' ant sitef7hel:ff'ects oflightning strikes should be included in the overall plant. fir #e protection program. ,(5)The consequences ofinadvertent operation of or a crack in a moderate energy line in the fire suppression system should meet the guidelines specified for moderate-energy systems outside containment in SRP Section 3.6.1. NUREG-0800. SRP, Section 9.S.1, Section C.S.b. Safe Shutdown Capability "(2) To meet the guidelines of Position C5.b.1, one of the following means of ensuring that one of the redundant trains is free of fire damage should be provided: (a) Separation of cables and equipment and associated circuits of redundant trains by a fire banier having a 3-hour rating. Structural steel forming a part of or supporting such fire barriers should be protected to provide fire resistance equivalent to that required of the barrier; Rev. G 6/24/98 3-130
DRAFT BWROG (' Shutdown Circuit Analysis Assessment Generic Guidance for Post-Fire Safe (b) Separation of cables and equipment and associated circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustible or fire hazards. In addition, fire detectors and an automatic fire suppression system should be installed in the fire area; or (c) Enclosure of cable and equipment and associated circuits of one redundant train in a fire barrier having a 1-hour rating. In addition, fire ' detectors and an automatic fire suppression system should Reinstalled in the fire area. g.E j^ $ I 4 ,m' l b .l NUREG-0800. SRP, Section 9.5.1. Section'C.6.a. Fire Detection M IW lt -n (1) Detection systeinissould be //6vided'fdr all areas that contain or present a. fire expohure to safetyt reisted ekuipment. ( t - [T>. ul r/,k { [i d'~ r y y e e i Generic Letter 86-10,; Enclosure 1; interpretations ofAppendix R. Item 5, ,(- Automatic Suppression and' Detection. Also Generic Letter 85-01, En' closure 3, IntkrpretatiordofAppendix R, Jtem 5. Automatic Suppression andDetection Q. W Section/ s III.G.2.b and III.G.2.c of Appendix R state that "In addition, fire ,deteTtors and automatic fire suppression system shall be installed in the fire area..." Other provisions of Appendix R also use the phrase " fire detectors and an automatic fire suppression system in the fire area..." (see e.g., Section III.G.2.e). In order to comply with these provisions, suppression and detection sufficient to protect against the hazards of the area must be installed. In this regard, detection and suppression providing less than full area I coverage may be adequate to comply with the regulation. Where full area . suppression and detection is not installed, licensees must perform an evaluation to assess the adequacy ofpartial suppression and detection to protect against the hazards in the area. The evaluation must be performed by a fire protection engineer and, if required, a systems engineer. L Although not required, licensees may submit their evaluations to the staff f' for review and concurrence. In any event, the evaluations must be retained I for subsequent NRC audits. Where a licensee is providing no suppression or detection, and exemption must be requested. ' Rev. G 6/24/98 3-131
i l l ) DRAFT BWROG ,}) Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment j l Generic Letter 86-10, Enclosure 2. Appendix R Questions and Answers, Section 3.1.5, Fire Zones. Also Generic Letter 85-01 Enclosure 6. Appendix R Ouestions and Answers, Section 3.1.5, Fire Zones QUESTION ...Does the requirement for detection and fixed suppressiN[ dicate that l the requirement can be limited to a fire zone rather th'an throughout a fire ..( l - [ area?... j 19 \\
~~RESPONSE~~
A i j ,1 f? p e N. v/ tt ... If altemate shutdown is provided on thnasis of robms or zones, the provision of fire dftectioh and fixe'd suppfission is only required in the room orEne undp co,nsideration.fComfliance with.Seclion III.G.2 cannot be based on rpoms or zonej" gi f f g h {s lrk JF Generic Letter 86-10, closure 2, Appendix R Questions and Answers, ) e 2 Section 3.8.3, Redundant Traim/ Alternate Shutdown. Also Generic Letter 85-01, EnclosWe'6, Appendix R Questions and Answers, Section 3.8.3, R~edundant Trains / Alternate Shutdown )#' QUESTION " Confusion exists as to what will be classified as an alternate shutdown system and thus what systems might be required to be protected by suppression and detection ~ under Section III.G.3.b. For example, while we are relying upon the turbine building condensate system for a reactor building fire and the RHR system for a turbine building fire, would one system be considered the altemative to the other. If so, would suppression and detection be required for either or both systems under III.G.3.b7 An explanation of alternative shutdown needs to be advanced for all licensees.
~~RESPONSE~~
"If the system is being used to provide its design function, it generally is j considered redundant. If the system is being used in lieu of the preferred Rev. G 6/24/98 3-132 i l' U
DRAFT BWROG (~ Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment system because the redundant components of the preferred system does not meet the separation criteria of Section III.G.2, the system is considered an alternative shutdown capability. Thus, for the example above,it appears that the condensate system is providing alternative shutdown capability in lieu of separating redundant components of the RHR System. Fire detection and a fixed fire suppression system would be required in the area where separation of redundant compdiists of the RHR system is not provided. However, in the event of a turbifie building fire, the RHR system would be used for safe shutdown and is not considered an alternative capability ( Howe'ver, one train'of the RHR system must be separated from the tu-binepuilding." g t lb Y gy' ~,y. j y ?) ,ic N$ ' 5 ll N C. ,, Connicting' Guidance // /' [,ys n R t!r Le - 'c 2 y i? 4 7 ? l $g i .h" s $, w - ? i / .i (! l l l l Rev.G 6/24/98 3-133
DRAFT BWROG Generic Gtadance for Post-Fire Safe } Shutdown Circuit Analysis Assessment 1 j.4p .g (, ~- n
~~i. t er e~~
~~b W l h h{ a f [., f u, t.: ?" q'" i ,1f h) f7' fN l l: lb .q?'% y, l l_F y ./ pt ({~ (e;' ~t I;~ e, p/ F~~
~~t. -~~
~ t t j' ic u U i. ,i ' ) a. f s, e, ny b. f- /j - t J Rev.G 6/24/98 3-134
DRAFT BWROG i Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 7.0 DEFINITIONS The following definitions are derived using the general industry recognized definition of the term around the time ofinception of Appendix R and are accepted for use by the BWROG Circuit Assessment committee. A The numbers in brackets [ ] refer to the IEEE Standards in which the. definitions are used. Refer to Section 2 of 380-1975 for full titles. g,I ff 2 (_ The BWROG definitions referenced in this section were produced by the BWROG committee where generally accepted definitions were notyvaipble. /j f. -( ~ Acceptable h4 / [ f 1 n IEEEStandardJ80-7N$hDemo;nstrated to y adequateby the safet9+ station. [308,387] r Pl; k# ' P' j ' N f '- $flQ f; ( Active safe shutdown compone'nt (equipment)7 N M
(#
BWROG definitidn-A sdfe s down component that changes physical state (e.g., start, stop, open, closef or operates-e.g., energize, run) to accomplish an Appendix R safe shutdown function /. }& Actuate Webster's New Collegiate Dictionary - To put into mechanical action or motion. Actuated equipment IEEE Standard 380-1975 - A component or assembly of components that performs a protective function such as reactor trip, containment isolation, or emergency coolant injection. l. NOTE': Thefollowing are examples ofactuated equipment: an entire control rod l and its release mechanism, a containment isolation valve and its operator, and a { safety injectionpump anditsprime mover. [379] r \\ I Rev.G 6/24/98 7-1
DRAFT BWROG Generic Guidance for Post-Fire Safe I Shutdown Circuit Analysis Assessment l l Actuation device (actuator) 1EEEStandard380-1975 - A component or assembly of components that directly controls the motive power (electricity, compressed air, etc.) for actuated equipment. ' Note: Thefollowing are examples ofan actuation device: a circuit breaker, a relay, and a pilot valve used to control compressed air to the,operatcr; ofa containment isolation valve. (379) j'g f b g Alternative (alternate) shutdown P ? fl h fi 6.,i If See ' Safe shutdown capability' [j. b /k El (f ll /k p
~~j,,~~
Associated circuits fr*%,,_, 5 / Ji Generic Letter 81 Those cables;(safety related, nonisafety related, Class 1 E, and non-Class IE) that }} 'i f I f' g n y ) Have a phyEcal sepdrati. 'les than,that required by Appendix R Section 1. t and; . j{ JY [L
~
h / 7 2. Have one 6f thetollowing: jf~ a. a common power source with the shutdown equipment (redundant or alternative) and the power source is not electrically protected from the circuit of concem by coordinated breakers, fuses, or similar devices, or b. a connection to circuits of equipment whose spurious operation would ' adversely effect the shutdown capability (e.g., RHR/RCS isolation valves, ADS valves, PORVs, steam generator atmospheric valves, instrumentation, steam bypass, etc.), or c. a common enclosure (e.g., raceway, panel, junction, etc.) with the shutdown cabics (redundant or alternative) and, (1) are not electrically protected by circuit breakers, fuses or similar devices, or - (2) will allow the propagation of the fire into the common enclosure. ] - Rev. G 6/24/98 7-2
1 DRAFT BWROG ( . Generic Guidance for Pest Fire Safe Shutdown Circuit Analysis Assessment l Cable IEEE Standard 100-1984 - A conductor with insulation, or a stranded conductor with e~ without insulation and other coverings (single-conductor cable) o a combination of conductors insulated from one another (multiple-conductor cable). [391] / g')' Cable Failure BWROG definition - the failure of a single conductor (wire) o,r multiple;$! conductors . (wires) within a single cable. See ' Circuit failure modes'.f l? [ W I [i A.,, g Q p'l Circuit .c2 V l$ fi* 't V IEEE Standard 100-1984 - A cotiductor or system of conductors through which an ~ electric currentjs inten&id.sto floM. [395]- l',a k / N C 'M m y o d Circuit failure m s 'I b n- \\' The following are%e ciresit failure ode that are postulated in the Appendix R Safe Shutdown Analysis as a r$s' ult eta fir,E#. U y p /* Hot short j BWROG deflI[ tion - A condition that results when an energized conductor comes in I electrical contact with a unenergized conductor (s). See 'Short circuit'. Open circuit BWROG definition - A condition that results when a circ 6it loses electrical continuity. I Short-to-ground BWROG definition - A' condition that results when a circuit (either a cable or j individual conductor within a cable) comes into electrical contact with a grounded conducting device (e.g., a cable tray, conduit, grounded equipment, etc.). l Rev.G 6/24/98 7-3 l
DRAFT BWROG s. Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment Class IE JEEE Standard 323-197J, IEEE Standard 380-1975 - The safety classification of the electric equipment and systems that are essential to emergency reactor shutdown, containment isolation, reactor core cooling, and containment and reactor heat removal, or are otherwise essential in preventing significant release of radioactive material to the ,.f
~~v.-~~
environment. gng', dJ fV r.: Class 1E electric systems g# fh ,F f. IEEE Standard 380-1975 - The systems that provide the electric power used to shutdown the reactor and limit the release of radioactive material following a design basis event. [308,336] 6^M 4 4 I ,tl .. ~ Class 1 electric equipment j // d y / IEEEStandard380 *1975 4The f}/eh.ric equipment that'ii' essential to the safe p p (" ( y and isolation of the reacto[or pose failure or daniage could result in significant release ) of radioactive mat'Erial. [334,3{44] ^f ~ ll }l Class I structures or equipment L/ L IEEE Standar#S80-1975 - Structures and equipment that are essential to the safe shutdown and isolation of the reactor or whose failure or damage could result in significant release of radioactive material. [308,336] Common enclosure IEEE Standard 380-1975 - An identifiable housing such as a cubicle, compartment, terminal box, panel, or enclosed raceway used for electrical equipment or cables. [384] BWROG clarification: shares safety related, non-safety related, Class IE and non-Class 1E circuits. See ' Associated circuits', Common power supply BWROG definition - A power source for associated circuits. See ' Associated circuits'. J Rev.G 6/24/98 7-4
) DRAFT BWROG f-Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment 1 Conductor IEEE Standard 100-1984 - A substance or body that allows a current of electricity to - pass continuously along it. [210,244,63] BWROG clarification: a single ' wire' within a cable; conductors could also be considered a circuit or a cable. f.,e* Dedicated shutdown capability ~ "i See ' Safe shutdown capability'. g# /. 'lf p Design basis events gf j,[ g lg Fn; h IEEE Standard 380-1975 - Postulated abnormal events tised i'n the design to establish the performance requirements for theI c'tures, systems, ar$1 component $j334,383] - W Nh h [F, t; h h Desigiibasis fire g4 G f* hj s 1 / $ /p e {. BWROGposition A postulate ev ~ ', f ,thebst-fire safe shutdown analysis. t used in R i Device i 9 IEEE Standard 50-1#75 - An item of electric equipment that is used in connection with, as an auxiliary)o70ther items of electric equipment. [344] Enclosure i IEEE Standard 380-1975 - An identifiable housing such as a cubicle, compartment, l terminal box, panel, or enclosed raceway'used for electrical equipment or cables. [384] Essential performance requirements 1EEE Standard 380-1975 - Requirements that must be met if a component, module, or L channel is to carry out its part in the implementation of a protective function. [379] l L C Rev.G 6/24/98 7-5 1
DRAFT BWROG . Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment l Exposure fire SRP Section 9.5.1 - An exposure fire is a fire in a given area that involves either in situ or transient combustibles and is extemal to any structures, systems, or components located in or adjacent to that same area. The effects of such fire (e.g., smoke, heat, or ignition) can adversely affect those structures, systems, or components important to_ safety. Thus, a fire involving one train 'of safe shutdown equipment may constituted ixposure fire for the redundant train located in the same area, and a fire involving combus'tibles other than either redundant train may constitute an exposure fire to both redtindant' trains located in l f the same area. / b El N Failure /o if h g-m / y 'i IEEE Standard 380-19Jf-The thination of[hembilit[of an item t$hrform its I requireJ functioneFsildres may be unannounced and not' detected until the next test (unannounced faihire), or they niayde amounced and detected by any number of methods at the inst' ant of obcurredcE(announced IailurE)ff1352] l [Jl$ } j'* f ~ ) I Fire area T { Generic Letter 8$10 jThe tefrii~" fire area" as used in Appendix R means an area sufficiently boufdedto' withstand the hazards associated with the fire area and, as necessary, to p$ tic'fimportant equipment within the fire area from a fire outside the area. In order to meet the regulation, fire area boundaries need not be completely sealed with floor to ceiling and/or wall-to-wall boundaries. Where fire area boundaries were not approved under the Appendix A process, or where such boundaries are not wall-to-wall or floor-to-ceiling boundaries with all penetrations sealed to the fire rating ~ required of the boundaries, licensees must perform an evaluation to assess the adequacy of fire area boundaries in their plants to determine if the boundaries will withstand the hazards associated with the area and protect important equipment within the area from a fire outside the area. Fire barrier SRP Section 9.5.1 - those components of construction (walls, floors, and their supports), including beams, joists, columns, penetration seals or closures, fire doors, and fire - dampers that are rated by approving laboratories in hours of resistance to fire and are used to prevent the spread of fire. ] ~ Rev.G 6/24/98 7-6
DRAFT BWROG (' Generic Guidance for Post-Fire Safe Shutdown Circuit Analysis Assessment Fire protection program 10 CFR 50, Appendix R, Section II.A - the fire protection policy for the protection of structures, systems, and components important to safety at each plant and the procedures, equipment, and personnel required to implement the program at the plant site. The fire protection program shall extend the concept of defense-in-depth to fire protection in fire areas important to safety, with the following objectives: AT"? To prevent fires from starting; ,p,' ia 6 f ({l I V ll To detect rapidly, control, and extinguish prom lptly th6se fires that do occur; is !?) ? that a fire that is notpromptly extitijuished'by;.the fi,r,hiporie To provide protection for stm6tI1Mi,3 systems',hd co I E e suppressiosgetivities will not ) prevent the-safelihstdown ofkhe plant. /Ji [,' p t$ y n r (' f,4E, ' Fire zone $p i ),V W E A J# BWROG definition - the hbdiksionkfJiriarea(s) for analysis purposes which is not necasarily bound by fire' rated; barriers. h Functional failure .y Generic Letter 86 the failure of the function of a component, that is, a component could be energized or de-energized. Thus, valves could fail open or closed; pumps could fail running or not running; electrical distribution breakers could fail open or closed. Also see ' Mechanistic failure'. Ground IEEE-Standard 100-1977-(earth)(1)(ground systems)- A conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to the earth, or to some conducting body of relatively large extent that serves in place of the earth. l l High impedance fault Generic Letter 86 fault below the trip point for the breaker on each individual circuit. See ' Multiple high impedance fault'. ) i Rev.G 6/24/98 7-7 l E _ _ _ _ _ _ _ _. _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - - _ _ _ _ _ _ _ _ _ _. - - -. - _ ~ )
DRAFT BWROG Generic Guidance for Post-Fire Safe ) Shutdown Circuit Analysis Assessment High/ low pressure interface See Section 3. Hot short ility 1 M wn capab y P 10 CFR 50, }fppen) dix R, Section III.G, footnote 2, Generic Letter 86-10 shutdown c4pability is provided by rerouting, relocating or modification [ sic] of existing systems and is used in lieu of the preferred system because the redundant components of the preferred system do not meet the separation requirements of Section III.G.3.2; alternative systems must be both physically and electrically independent of the control room. Dedicated shutdown 10 CFR 50, Appendix R, Section III.G, footnote 2 - Dediceted shutdown capability is provided by installing new structures and systems for the function of post-fire shutdown. Safe shutdown analysis See Section 3. Rev. G-6/24/98 7-10
DRAFT BWROG k Generic Guidance for Post Fire Safe Shutdown Circuit Analysis Assessment Safe shutdown component (equipment) BWROG definition - A component required by Appendix R to perform a safe s1.idown function. . Separation distance f I IEEE Standard 380-1975 - Space without interposing structures,1ciquipnient, $r materials that could aid in the propagation of fire or that could disable'the Glass IE system. [384] 4 V Short circuit ,/. fi f sw hk Es! IEEE Standard 100-1977 - An abnormal connection (includiEg an arc [E ofrelatively low impedance, whether made accide{i h s[or intentio'$ ally, $ d8etwe'en tw tally potential. Note: T)v?einfault ors o circuit'faillt is u e to desctibia short circuit. y n e i+ m Short-to-ground S* c-e y'r 2 See ' Circuit failurefmodes.,.,i If Shutdown pathsf N BWROG definjtforr-A specific combination of analyzed systems and components capable of achieving and maintaining a' safe shutdown condition during and following a design basis fire. Single failure criterion IEEE Standard 380-1975 - The system shall be capable of performing the protective actions required to accomplish a protective function in the presence of any single detectable failure within the system concurrent with all identifiable, but nondetectable failures, all failures occurring as a result of the single failure, and all failures which would be caused by the design basis event requiring the protective function. Spurious actuation (or operation) L
~~BWROG definition - The inadvertent operation or repositioning of a component.~~
Examples of a spurious actuation includes: start, stop, open, close. Rev.G 6/24/98 7-11 = l
DRAFT BWROG Generic Guidance for Post-Fire Safe -) Shutdown Circuit Analysis Assessment <, : r, t ,.-S A i L f
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t-g f; r, ,.. /", r!. U. ,, ~ n a,. .c p; 6 4 a r> tr v.c .e 50 ' ' E t Rev. G 6/24/98 7-12
[ GE Nuclear Energy j BWR Owners' Group i GeneralElectric Company l 175 CurtnerAve San Jo.se CA 95125 OG98-0288-2 '.6 Project 691 July 10,1998 l t Document Control Desk US Nuclear Regulatory Commission Washington, DC 20555-0001 l ATTN; Leon E. Whitney, Plant Systems Branch
~~SUBJECT:~~
~~BWR Owners' Group Appendix R June 30,1998 Short Meeting Summary~~
~~Attachment:~~
NRC/BWROG June 30,1998 Meeting Short Summary l The BWRv0wners' Group Appendix R/ Fire Protection Committee short summary of the June 30*,1998 meeting with the NRC is attached. Please include this summary with the NRC meeting summary as agreed in the meeting. The BWR Owners' Group Appendix R Committee appreciates the opportunity to provide this summary information.
~~Regards, h~~
Georg Stramback, Project Mab r BWR owners' Group Appendix R Committee Tel: (408) 925-1913 Pager: (408) 488-0558 E-Mail: george.stramback@gs ne.ge.com Attachment ec: TJ Rausch, BWROG Chairman WG Warren, BWROG Vice Chairman JH Wilson, NRC F Emerson, NEl DB Townsend, GE BWR Owners' Group Appendix R Committee ATTACHMENT 4 i
Attachment NRC/BWROG 6/30/98 Meeting Short Summary The Steering Committee of the BWROG Fire Protection - Appendix R Committee met in a public meeting with the NRC Fire Protection Section staff en June 30th,1998 in Baltimore, MD to discuss sections of a draft BWR Owners' Group (BWROG) guidance document. Draft Sections 3.0,3.117.0 of BWROG Generic Guidance for Post-Fire Safe Shutdown Circuit Analyses Assessment, Revision G, dated 6/24/98 were provided to the NRC prior to the meeting. The preliminary draft document was the principal subject of the meeting, along with introductory discussion of the Committees plans and the background effort already expended in preparation of these portions of the document. The meeting summary is as follows: The BWROG reviewed the Fire Protection Committee's history, including the extensive work already completed during preparation of the guidance document. The Fire Protection C'ommittee identified its intent to submit the final document as a Licensing Topical = Report (LTR) for NRC review and issuance of a Safety Evaluation Report (SER). The approved LTR guidance document could be used to assist BWR licensees in responding to an NRC Generic Letter (GL) which is in development. There was a good exchange of NRC insights, hierarchy of guidance documents, willingness to e comment on the prioritization of positions that the Committee will be developing. The discuss $on was open, cooperative and very informatnre. = All of the material on the agenda was discussed, including the regulatory guidance documents and definition sections of the draft document with very beneficia! feedcack from the staff. BWROG & NRC discussed the apparent incompatibi!! ties of schedules for development of the LTR e and the GL; however, these schedules could be characterized as being relatively close. The BWROG planned to complete the draft position statements at the end of the 1" quarter of 1999, with LTR submittal at the end of the 2nd quarter 1999. NRC staff identified their preparation of a Regulatory Guide targeted for issue in September 1999. BWROG asked to be involved in the initial developmental stages of the Regulatory Guide. NRC requestet ist the BWROG Fire Protection Committee provide a letter describing the plans and program for development of the guidance document. NRC requested that the BWROG Fire Protection Committee provide a letter with the bases for the BWROG proprietary claim for protection of the preliminary draft documentation that would be discussed with the NRC staff. NRC agreed to meet with the BWROG for review ofinitial(pilot program) position statements approximately mid-September. NRC willidentify to BWROG any additional topic areas or reference documents that could be addressed in the guidance document. Points-of-contact for NRC and BWROG were identired. Meeting summaries will be developed separately by NRC and BWROG; however, a short BWROG summary will be provided for attachment to the NRC meeting summary, i OG96 0288-216 ATTACHMENT 4 .__}}

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