memo from harold denton to william j. dircks re control ... · table of contents (continued) list...

I i I W I

JUN 29 1984

William J. DircksExecutive Director for Operations

/STRIBUTIOP

DMul 1 erRBel I amyWJohnstonFMiragl ia

LRubensteinWRussellActing D/DSIHDenton

HEMORANDUM FOR:

FROM:

SUBJECT:

Harold R. Denton, DirectorOffice of tNuclear Reactor Regulation

CONTROL ROOM HABITABILITY

I am pleased to provide a copy of the Staff Report on Control RoomHabitability. This report was prepared as directed in your A!-just 15,1983 memo to me, and addresses the concerns identified by the ACRS aswell as other concerns identified by the control room habitabilityworking group.

As noted in my March 15, 1984 memo to you, we have not yet completed thepart of the program Involving a survey of as-built control rooms. Weplan to provide the results of this part of the review by October 1,1984 via a supplement to the Staff Report on Control Room Habitability.We anticipate that the infornation contained in the October supplementwill not modify the conclusions and recommendations contained in theReport; however, additional conclusions and recommendations may be made.

I plan to implement tne recom endations presented in this reportconsistent with the prioritization process and the fiscal and personnelresources available to me. :Some of the recommendations may requireretrofits. Any generic action will be taken through the normal genericissue resolution process including CRGR comments. Once resolved, aGeneric Letter, an IE Bulletin, or a multilplant action, as appropriateto the recommendation, will be instituted. For those recommendationswhich involve additional study, the action to be taken will bedetermined on a case by case basis.

4aO tL.0

-0

am.UW*sn

This report represents the culmination of an intensive effort on thepart of a dedicated group of staff members and I wish to commend theWorking Group: U. P..Gamnill; J. J. Hayes; K. Dempsey; R. Eckenrode;R. Feit, R. Ferguson; U. Pasciak; and B. K. Singh for a Job well done.I would also like to commend Phil Matthews who provided valuableassistance to the working group.

. . .

bcc: WGammnill WPasclak witmJHayes BKSIngh ILlKDempsey PMatthewsREckenrode HaroldRFeit OfficeRFer-guson

Enclosure:Staff Report on Control Room Habitability*SEE PREVIOUS CONCURRENC_

L ktsl b k'

±0 f

/,,XV -k

/ f- 6/ 'Z-l

on 1

1 9ftiR

R. Denton, Directorof Nuclear Reactor Regulati

II \

. _

. .

C01n i z DSI:RPM e. * . ... ...f .. *....J

JRNAME~ DR u l rCS[

. 7

RI*

RBel Ilamygyp 090604

DE:MC&ET*.- DL:SA*:~

WJohnston R1ira. glia, ~ s 0 V I V

A~- _ a - a 2 _Ie ~ '- . 1h W%

I

DSI:CPS*'''!"Cv* | ..... .

LRubenstetinMUM ..4......

IDHFS* 6sf :Acti r* * * . . . . * * 5 e n . S * * . ..** *

WRussell1 ORMull1er!

1109"' WAX5*S**5

.

:FORMI I � .., -... 1 � � , �CIPY 1, Q-,-�7ss-, � "I''

t , .P 0

I

:twlj

DISTRIBUTIONCENMRL f ILEADRP RFOflulIerRBellamyWJohnstonFillraglia

OR: William J. Dircks LRubensteinExecutive Director for Operations

Harold R. Denton, DirectorOffice of Nuclear Reactor Regulation

4.r

WRussellRiattsonHOenton

I

ii

HmEIORANDtR Fc

'ROM:

SUBJECT:

'I-,'A

CONTROL ROON HABITABILITY

I am pleased to provide a coy of the Staff Report on Control Room Habitability.This report was prepared as d liected In your August 15, 1983 emo to me, andaddresses the concerns identified by the ACRS as well as other concerns iden-tifled by the control room habitA ility working group.

As noted in my March 15, 1984 memo \o you, we have not yet completed thepart of the prooram involving a survey of as-built control rooms. le planto provide the results of this part of the review by October 1, 1984 via asupplement to the Staff Report on Control Room Habitability. We anticipatethat the information contained in the October supplement will not modify theconclusions and recomiendations contained in the Report; however, additionalconclusions and recommendations may be made..

I plan to implement the recommendations presented In this report consistentwith the prioritization process and the ffiscaltand personnel resources avail-able to me. Sone of the reconmendations)May require retrofits. If they do,they will be taken through the normal progression chain to obtain CRGR approval.If CRGR approval is obtained, a Generic Letter, an IE Bulletin, or a multi-plant action, as appropriate to the recommendation,\ will be instituted. Forthose recommendations which involveltdditional studyt the action to be takenwill be determined on a case by caf'e basis.

This report represents the culmination of an intensive effort on the part ofa dedicated group of staff membefs and I wish to commend~the Working Group:H. P. Gammtill; 3. J. Hayes; K.- Dempsey- R. Eckenrode: R. Felt; R. Ferguson;W. Pasciak; and B. K. Singhfor a Job well done.,

I would also like to conumnd Phil Matthews who provided valuable assistanceto the working group. /

bcc: H1. Gammill R., ergusonJ. Hayes 14 PasciakK. Dempsey .- Singh Harold R. Denton, Director'e a qR. Eckenr e''P. Matthews O f c fIu l a e co

Enclosure: -. RRStaff Report on Control Room Habitability l - lDen*SEE PREVIOUS CONCURRENCE.w. ton

/84,

DSI:RP REGION I* - DE:tlC&ET* DL:SA* DSI:CPS* JHFS*.~~.... .... ..... *..... .*..*. x ii .. S.. YY ......... 11

, mcat go0 RB-ell1fy ...... TU~MUM .... 'NM'Fa'gT a u.ns en Russe tsgSUR8AMEV ..... V984-.....- I* * '**** 5131184::: 5130184' '5t/O/3 84I - . I : 7.,..DA~t ). . . . . ' ? : ; ~ " ' * * '> ..... ....

.-W fNORMC .: , ' .. OFFICIAL'lRECORD .C ! '> '- I ' ' 'u, ,a, - 7.--

a I

William J. DircksExecutive Director for Operations

Mxnl R hnfn-flrptn

DISTRIBUTIONCENTRAL FILEADRP RFDMullerRBellamyWJohnstonFMfragl IaLRubensteinWRussell;. 5*

RMattson -;HDenton

MEIIORANOU14 FOR:

FROMM

Office of Nuclear Reactor Regulation p

SUBJECT: COUTROL ROOM HABITABILITY',

I am pleased to provide a copy of the Staff Report o/Control RoomHabitability. This report was prepared as directedlin your August 15.1983 memo to me, and addresses the concerns Idenifed by the ACRS aswell as other concerns identified by the control/room habitabilityworking group.

As noted in my March 15, 1984 memo to you, w have not yet completed thepart of the program involving a survey of ^-built control rooms; 'leplan to provide the results of this part of the review by October 1,1984 via a supplement to the Staff Report, on Control Room Habitability.We anticipate that the information contained In the October supplementwill not modify the conclusions and rO'commendations contained in theReport; however, additional conclus 1ns and recormiendations may be made.

/ , 1*.

This report represents the culmination of an intensive effort on thepart of a dedicated group of staff members and I wish to conmend theWorking Group: W. P. Gammril; I 1 J. Hayes; K. Dempsey; R. Eckenrode; R.Felt; R. Ferguson; W. Pasciak; Knd B.-K. Singh for a Job well done.

I would also like to co-mend P I1 Mathews who provided valuableassistance to the working grd'up. 9 ,`-

/ . - . *4

Harold R. Denton, DirectorOffice of nluclear Reactor Regulation

I.t.�l.-1Iiiz

I

I

e

0z

1�

Jfi

Iiil

f

-

Enclosure:Staff Report on 7 Grol Room Habitability

;~~. s.. '.

..W WJohnsto j fFMiraglia LRubenstiwo~~~~- - - - -------------------.s .. , ,;.

CONTROL ROOM HABITABILITY

Control Room Habitability Working Group

U.S.tNuclear Regulatory Commnission

Washington, D.C. 20555

June 1934

8407100203 840629CF SUEJID&R-5FAC LIC CF

TABLE OF CONTENT

Page

1 BACKGROUND ........................................................

1.11.21.31.41.5

Background...................................................ACRS-NRC Interaction.........................................The Program Plan.............................................The Steering Committee.......................................The Working Group . . . ................................

2 APPROACH..........................................................

2.1 Phase 1......................................................

2.1.1 Oetermination of Habitability Criteria................2.1.2 Workshop ................... ::2.1.3 Familiarization With Habitability Review Areas........

2.2 Phase 2..........

2.2.1 Final Determination of Habitability Parameters........2.2.2 Application of NRC Review Process to NTOL Plant.

2.3 Phase 3......................

2.3.1 Selection of Plants To Be Surveyed....................2.3.2 Scope of Work of Control Room Survey..................

2.4 Support From Office of Research.............................

3 DESCRIPTION OF NRR REVIEW PROCESS.................................

4 FINDINGS OF THE WORKING GROUP....................................

4.1 Introduction................4.2 Recommendations............................ ..

1-1

1-11-11-21-31-3

2-1

2-1

2-22-32-3

2-3

2-32-4

2-5

2-52-5

2-7

3-1

4-1

4-14-1

4.2.14.2.24.2.34.2.44.2.54.2.64.2.74.2.8

RecommendationRecommendationRecommendationRecommendationRecommendationRecommendationRecomendationRecommendation

I......................................2................................3 . . ..............

4................................... ...5......................................6......7...........a......................... ...........

4-14-34-44-54-64-94-94-10

5 CONCLUSION........................................................ 5-1

Control Room Habitability i1

_ M I oI= -- a

APPENDIX A

APPENDIX B

APPENDIX C

APPENDIX D

APPENDIX E

Table

1-1

3-1

B.1-1

9.2-1

8.3-1

B.4-1

8.5-1

8.6-1

B.7-1

TABLE OF CONTENTS (Continued)

CONTROL ROOM HABITABILITY WORKING GROUP (CRHWG) RESPONSESTO ACRS COMMENTS AND RECOMMENDATIONS

CONTROL ROOM REVIEW PROCESS AS DETAILED IN NUREG-0800 ANDAS ACTUALLY PERFORMED BY NRR BRANCHES

PROPOSED CONTROL ROOM HABITABILITY CRITERIA

FAILURE RATE OF EQUIPMENT AFFECTING CONTROL ROOM HABITABILITY

NRC INSPECTION ACTIVITIES ASSOCIATED WITH CONTROL ROOMHABITABILITY

List of Tables

Pag~e

Summary of ACRS Conceros and Recommendations on ControlRoom Habitability ............. : ;

Abbreviations*Referenced in Control Room Reviews............

SummaryControl

SummaryControl

SummaryControl

SummaryControl

SummaryControl

SummaryControl

SummaryControl

of AEB Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of ASE Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of CMEB Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of HFEB Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of METS Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of RAB Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

of SAB Review Responsibilities With Respect toRoom Habitability As Detailed in the SRPs...........

1-5

3-4

B-3

B-6

B-10

B-15

B-19

B-22

B-24

C-S

D-2

D-5

E-3

C-I Proposed Control Room Habitability Criteria.

O.1-1 Conirol Room Air Conditioning and Ventilation System LERs(October 1977 - December 1983)..............................

D.2-1. LERs Involving Fire Protection in Control Room EmergencyZone (January 1981 - December 1983).........................

E.2-1 Inspection Objectives IE Module SO10...

Control Room Habitability iv

TABLE OF CONTENTS (Continued)

List of Tables

Table Page

E.3-1 Inspection Objectives, Requirements, and Guidance of IEModule 83524 (External Occupational Exposure Control -Preop) ...................................................... E-8

E.3-2 Inspection Objectives, Requirements and Guidance Of IEModule 83525 (Internal Exposure Control and Assessment -Preop) ... E-9

E.4-1 Guidance Contained in Emergency Preparedness ProgramTemporary Instruction 2155/55, Reference 1 .................. E-16

List of Figures

Figure Page

3-1 Control Room Habitability Block Diagram Showing Branches,Major Review Areas, and Interfaces ........................... 3-3

A-1 Summer and Winter Comfort Zones and Thermal Tolerances forInhabited Compartments (MIL-STD-1472C, May 2, 1981) .......... A-6

B.1-1 Interaction of AEB With Other Branches in Control RoomReviews As Noted in the SRPs ................................. 6 -4

6.2-1 Interaction of ASB With Other Branches in Control RoomReviews As Noted in the SRPs ................................. B-8

B.3-1 Interaction of CHEB With Other Branches in Control RoomReviews As Noted in the SRPs ................................. 8-13

B.5-1 Interaction of METB With Other Branches in Control RoomReviews As Noted in the SRPs. B-20

6.7-1 Interaction of SAB With Other Branches in Control RoomReviews As Noted in the SRPs ................................. B-26

Control Room Habitability v

=MIMM _

CHAPTER I

BACKGROUND

1.1 Introduction

Since 1980, The Advisory Committee on Reactor Safeguards (ACRS) has held sever-al meetings with the NRC Staff (Staff) to discuss the subject of control roomhabitability. During this period the ACRS has also discussed this topic withnumerous applicants for a near-term operating license (NTOL) and with variousnuclear steam supply system (NSSS) vendors. In addition, the ACRS has solicitedinformation from consultants and architect-engineers.

1.2 ACRS-NRC Interaction

In a March 11, 1980 letter, the Chairman of the ACRS indicated to the Chairmanof the NRC that the Staff's goal of "confirming compliance with exilting Regu-latory Guides and Standard Review Plan" for Item III D.3.4, "Control Room Nab-itability" of Draft 3 of NUREG-0660, may be insufficient. The letter Indicatedthat the ACRS was concerned that "existing requirements to protect the occu-pants of the control room against radiation may not be adequate, particularlywith respect to leakage control and arrangement of air intakes."

Subsequently, there have been several meetings between the ACRS and the staffwhich have resulted in ACRS letters that express specific concerns, and thestaff has provided responses in reports and meetings. Table 1-1 summarizesthe ACRS's general and specific comments as described in its most recentletter dated May 17, 1983.

In addition to the comments and recommendations presented in Table 1-1, theACRS requested in that same letter that the Staff:

(1) Determine the impact on control room habitability with the loss of(a) AC power;(b) auxiliary services to chillers;(c) service air; and(d) component cooling water.

(2) Evaluate all potential sources of heat input in the control room necessaryfor determining temperature increases while the HYAC system is in degradedoperating modes.

(3) Determine the potential need for monitoring 02 concentrations and steamintrusion In the control room.

(4) Evaluate whether the present detection limits of toxic-gas monitors aresufficient to protect personnel.

Control Room Habitability Report 1-1

�1

The [DO determined that a substantial amount of Staff tim* and effort was beingexpended in responding to the ACRS concerns, but little was being accomplishedin the way of resolving the itsue of control room habitability. Therefore, OnJune 7, 1983 he Instructed the Offices of Nuclear Reactor Regulation (NRR) andInspection and Enforcement (RE) to develop a plan to handle the Issues raisedby the ACRS, to report to him specific proposed courses of action to respond tothe ACRS's concerns, and to identify resources needed and a schedule ofimplementation

1. 3 Ine Progr!m Plan

On July 27, 1983 the Director of the Office of NRR submitted to the EDO, forhis approval, a program plan developed by NRR and IE to handle the issuesraised in the ACRS letter of May 17, 1983. On August 15. 1983 the EDO approvedimplementation of the program plan and by memorandum directed NRR to coordinatewith IE and the NRC regional offices, as appropriate, a program which wouldpermit a detailed evaluation of the concerns expressed by the ACRS to be pertormed. The EDO directed that a regional representative participate and that areport be submitted to him before June 1, 1984. This is that report.

The intent of the program plan was to astess the integrated response of the NRCin the area of control room habitability. The plan was designed to establishwhether, and in what areas, problems exist and, if they exist, to implementrecommended changes. To administer the program plan a working group was formedwhich was comprised of five individuals drawn from the technical branches mostintimately involved in the control room habitability issue. These were theMeteorology and Effluent Treatment Branch (METS), the Auxiliary Systems Branch(ASB), the Chemical Engineering Branch (CMEB), the Accident Evaluation Branch(AEB), and the Human Factors Engineering Branch (HFEB).

The working group activities were directed by a lead project manager familiarwith the Issues related to control room habitability. The working group wasresponsible for the detailed analysis and evaluation needed to scope the prob-lem and for the development and implementation of recommendations.

A steering group, comprised of the supervisors at the Deputy Director or Assis-tant Director level of the branches listed above, plus a representative fromthe Division of Licensing (Dl) was formed. It consisted tf the: AssistantDirector for Radiation Protection, Division of Systems Integration (OSI); As-sistant Director for Core and Plant Systems, DSI; Assistant Director for Mate-rials, Chemical and Environmental Engineering, Division of Engineering (DE);Deputy Director, Division of Human Factors Safety (DHFS); and Assistant Direc-tor for Safety Assessment, DL. The steering group provided general administra-*tive support and management direction to the working group and the AssistantDirector for Radiation Protection acted as chairman.

The program plan consisted of five main areas. The first Involved the reviewof the present-criteria for control room habitability. These criteria were tobe evaluated; modifications to the criteria were to be considered where inade-quacies exist and new criteria were to be developed where none existed.

The second part of the program plan involved the performance of several reviews.For each NRR branch, review areas were to be identifled. IE and regional


inspection activities were to be identified along with present programs in theOffice of Research (RES). Information on system/tquipsunt failure modes andrates was to be gathered. Three to five near-term operating license (N7OL)FSAR/SERs and three to five operating plants, being reviewed under TMI ActionItem II.0D.3.4 (multi-plant action item F-70), were to be reviewed for consis-tency between perceived responsibilities and actual staff practice. Theadequacy of review areas, criteria, documentation, interfaces, and staff prac-tice was to be assessed and the issues raised b the ACRS were to be covered.

The third part of the program plan involved the survey of the as-built controlrooms of three to five NTOL plants and the three to live F-70 plants for(1) consistency between requirements and practice and (2) actual practice incomponent and Integrated testing. The working group was to confer with selectedarchitect engineering firms to discuss their control room design practices.

After these three parts of the program plan were completed, a report was to bewritten (the fourth part) which would provide recommendations and would specifythe manner In which each of the recommendations would be handled in the regula-tory process.

The fifth part of the program plin would involve maintaining an overview andmanagement responsibility for implementing the recommended changes, evaluatingthe adequacy of implementation, and developing the overall strategy for movingthe recommended changes through the regulatory process. The working group andsteering group would be maintained during this period, but the detailed imple-mentation of recommendations would likely be delegated to the appropriatebranches. If the efforts resulted in new requirements which necessitated in-spection to verify implementation, then IE would incorporate revisions into theinspection program.

1.4 The Steering Committee

The steering committee consisted of the following individuals:

D. R. Muller (Chairman), Assistant Director for Radiation Protection, DSIR. R. Bellamy, Chief, Radiological Protection Branch, Region IW. V. Johnston, Assistant Director for Materials, Chemical and Environmental

Technology, DEF. J. Miraglia, Assistant Director for Safety Assessment, DLL. S. Rubenstein, Assistant Director for Core and Plant Systems, OSIW. T. Russell, Deputy Director, DHFS

1.5 The Working Group

The control room habitability working group consisted of the followingindividuals:

W. P. Gammill (Deputy Chairman), Meteorology and Effluent Treatment Branch, NRRJ. J. Hayes, Jr. (Project Manager), Meteorology and Effluent Treatment Branch,

NRRK. C. Dempsey (Deputy Project Manager), Accident Evaluation Branch, NRRR. J. Eckenrode, zuman Factors Engineering Branch, NRR

Control Room Habitability Report -1-3

R. L. Ferguson, Chemical Engineering Branch, NRRB. K. Singh, Auxiliary Systems Branch, NRR

The RES representative to the working group was Mr. R. Felt of the Instrumenta-tion and Control Branch. The regional representative was Mr. W. J. Pasciak ofRegion I and the IE representatives were Mr. G. Barber and Mr. P. F. McKee ofthe Operating Reactors Program Branch.


Table 1-1 Summary of ACRS ConcernsHabitability

and Recommendations on Control Room

ACRS Concern: ACRS Recommendation:

General Comments

1. NRC review is fragmented.

2. NRC does not perform an indepen-dent 'valuation of the controlroom. Consequently, the NRC doesnot kno, whether the control roomenvelope .;;. '^r.. m as intended.

3. NRC has not utilized varioussources of data on equipment.orsystem failure to determine theimpact of these failures on thehabitability of thtk control room.

1. One NRC group should be designatedfor coordinating the review andevaluating the control room.

2. NRC should perform critical andIndependent reviews of the controlroom.

3. NRC should utilize regional officesand INPO to obtain data on equip-ment and system failure:

Specific Comments

1. Assistance could be provided inthe determination of the optimumlocations of alternate air intakesfor control rooms through the useof a generic diffusion study.

2. Temperature limit of 120IF forthe control room is unacceptable.Additional conditions such as lowair exchange rate, perspiration,ESF filter system heaters, etc.could affect habitability.

1. NRC should reevaluate itsresponse on the use of a genericdiffusion study for determiningthe optimum location of controlroom intakes.

2. Temperature limits should berevised taking into account lowair exchange rate, operation ofESF filter system heaters, andperspiration.

3. NRC does not have afor testing controlsystems.

protocolroom HVAC

3. NRC should develop a protocol fortesting control room HYAC. Protocolshould include determination offunctionability of equipment,human comfort, complete filtersystem testing under positive andnegative pressures, and impact ofpressure surges.

Control Room Habitability Report l-5

I

Table 1-1 (Continued)

ACRS Concern: ACRS Recomaendetion:

4. NRC is not giving an appro-priate amount of attention tothe quality assurance aspectsof HEPA filter manufacturing.installation, and testing.

5. Fire dampers are not designedto prevent the spread of smokeor toxic gases through thecontrol room.

6. NRC has dismissed the use ofdeep bed charcoal fbr treatmentof toxic gases.

4. NRC regional offices should inves-tigate whether NRC licensees arepurchasing HEPA filters which donot meet RG 1.52. and take correc-tive action if needed. NRC shoulddetermine whether QPL testing isrequired from CONAGT. RG 1.52should be revised accordingly.

5. NRC should determine the allow-able leak rates for fire dampers,whether such leak rates can beachieved in practice, and whetherauxiliary dampers should beinstalled to limit leakage.

6. NRC should consider dee; beds asa means of treating contaminants.


I

��M �M=

CHAPTER 2

APPROACH

The control room habitability study was performed in three phases which coverthe areas of the program plan described in Chapter 1. Phase 1 consisted of thedetermination of parameters that must be considered important to habitability.In addition, time was spent familiarizing the working group with the reviewperformed by each of the branches having major review responsibilities in thearea of control room habitability. Members of the working group described theirbranches' review procedure and their acceptance criteria. Phase I was also aperiod of information gathering. Sources outside the NRC were asked to addressparticular areas that they were familiar with and to provide comments on thoseareas of control room habitability that they may employ during their normal workassignments. This phase culminated in the control room habitability workshopwhich was held on November 28 and 29, 1983 in Harpers Ferry, West Virginia.

Phase 2 involved the fiqnal determination of the control room habitability param-eters, the selection of a near-term operating licensee (NTOL) plant where theworking group would apply the present NRC review criteria, identification ofthose areas in which the present NRC review criteria are inadequate, and assess-ment of how the system design, as presented in the FSAR, is transformed to theas-built system. The latter assessment involved a site visit on January 24-25,1984 to review the control room design of the NTOL plant selected for review.

Phase 3 involved the review of as-built control room designs at an NTOL plant andat two operating plants. These reviews are being performed under a technicalassistance contract and are not scheduled for completion until September 1984.The results of these reviews will be reported in a supplement to this report inOctober 1984.

2.1 Phase I

Phase 1 was spent:

(1) securing background information on habitability criteria of otherorganizations;

(2) providing a critique of present NRR staff review practices of control rooms;

(3) obtaining a perspective of how other organizations view the ACRS's concernsand recommendations; and

(4) determining which parameters are important to control room habitability andshould be included in the design criteria.

b.

Phase I was also a period during which the working group attempted to refinethe program plan so that It would serve the study rather than direct it. Themost striking refinement was that the working group established very early Inits deliberations that the purpose of the group was not just to address thecomments and recommendations of the ACRS. Rather, the group would focus on thesubject of control room habitability as if it were a new safety area. Theeffort was made to place past practices in the background and to approach thesituation as If it and its practices were being Initiated today.

2.1.1 Determination of Habitability Criteria

One of the first orders of business for the working group was to develop adefinition of a hibitable control room and to identify the various parametersthat must be maintained in order that the control room remain habitable.

Initially, it was established that the habitability goal was:

To maintain the physical and environmental state of the controlroom such that it will allow the inhabitants to perform theirintended functions unimpaireO under both accident and normaloperating conditions.

The working group agreed that the function of the control room operator is tomaintain adequate control of the nuclear chain reaction so that the reactor isoperated safely under normal conditions and is maintained in a safe conditionin abnormal situations. Therefore, it is imperative that everything withinreason be done to ensure that the control room operator is in a situation wheresuch control may be maintained.

The conditions that affect the manner in which a control room operator performshis duties are similar to those that affect any worker. A worker functionsbest when he is safe, comfortable, stimulated, and confident. Thus, if a con-trol room operator is free from large fluctuations in environmental parameterssuch as temperature, relative humidity, lighting, noise, odors, and such, he ismore likely to perform his tasks in a correct and safe manner. The operatorcan respond in a stimulated and confident manner if he knows that the tools orfacilities necessary to perform the job are available. Such requirements wouldinclude adequate work space, access to communication equipment and other equip-ment and tools necessary to perform the Job, and the capability to interactwith the appropriate individuals necessary for the job. In addition, the oper-ator must feel that he is free from physical threats, whether they be real orimagined. Such threats could take the form of physical violence or attacks onone's health such as might occur from release of toxic gases or radioactivity.

Keeping all of these requirements in mind, the working group determined that thefollowing items were important in establishing habitability criteria for thecontrol room:

(1) radiological exposure (dose);(2) communications;(3) visibility;(4) noise;(5) illumination;


I

(6) ventilation(7) temperature;(B) relative humidity; and(9) contaminant levels (toxic gases)

2.1.2 Workshop

The working group sought to enlist the expertise of various industries andorganizations that had habitability concerns for individuals in the course oftheir daily business and to learn how these organizations approach the problemof habitability. The working group received input from consultants, architectengineers, nuclear steam supply system (NSSS) vendors, academia, and governmentagencies and departments. Specifically representatives from NASA, the Depart-ments of the Army and Navy, the National Bureau of Standards, Bechtel, Under-writers Laboratories, Florida Power and Light, Duke Power Company, Sargent andLundy Engineers, U.S. Navy Research Laboratory, Nuclear Consulting Services,Inc., General Electric Co., Offshore Power Systems, and the Department of Indus-try and Technology of Northern Illinois University were consulted. Invitationswere extended to participate in a workshop on control room habitability. Eachgroup was asked to address the ACRS comments and recommendations. Their viewswere presented at the control room habitability workshop (November 28 and 29,1983, Harpers Ferry, West Virginia).

2.1.3 Familiarization With Habitability Review Areas

Phase I was also a period when each of the working group members broadened hisknowledge in the review area of control room habitability. Most of the workinggroup members were familiar with only one branch's review responsibility otherthan their own. Most were not aware of all of the branches involved in thereview process and the responsibilities associated with that review. Phase 1was a period during which the working group attempted to become familiar withboth.

During this period each member of the working group prepared a presentationdescribing how his branch reviews those aspects of the control room design re-lated to habitability. The intent of this presentation was to allow a critiqueof the review procedures as described by the working group members.

On several occasions topics were raised in which the question had to be askedwhether the topic fell within the purview of this study, i.e., dealt with con-trol room habitability or control rooms as a whole. The remote shutdown panelwas one such topic. On the basis of a discussion between the ACRS SubcommitteeChairman, Dr. Dade W. Moeller, and the working group's program chairman, it wasdetermined to include the remote shutdown panel on a limited basis in the review.

2.2 Phase 2

2.2.1 Final Determination of Habitability Parameters

Initially the working group believed that separate habitability criteria cover-ing the environmental parameters defined in Section 2.1 should be defined forboth normal operation and accident conditions. This would have been inconsist-ent with the present NRC practice which has established most of the controlroom habitability criteria for normal operating conditions. The exceptions are


the toxic gas challenge and the radiological accident. The present habitabilitycriteria allow these environmental parameters to degrade during the course ofan accident. After hearing a discussion at the workshop on performance understressful conditions by an ergonomist and other individuals involved in humanfactors, it was the consensus of the working group that the conditions underwhich a control room operator must function should be as good, if not better,during an accident as they are during normal operation.

In an attempt to implement this philosophy, the working group first determinedthe present requirements for normal operation associated with the various habit-ability parameters and second, assessed whether these requirements allowed theoperator to maintain performance during normal operation. Then, the workinggroup assumed these requirements were applied to an accident situ.tion. Thegroup assessed whether these requirements still provided an environment in whichthe operator would continue to function in the intended manner. The workinggroup found that some requirements were not defined for normal operation, butonly for accident conditions. The allowable toxic gas concentration given inTable C-i of RG 1.78 is such an example. The working group concluded thatpotential problem related to chronic exposure to toxic materials is not uniqueto the control room Personnel and should be left to the plant industrialhygienist. The radiological dose-parameters present a different problem.Normal operation is governed by the criteria of 10 CFR Part 20. Howfever, foraccident conditions, the doses are allowed to be increased to the levels ofGDC 19 and SRP 6.4.

2.2.2 Application of NRC Review Process to NTOL Plant

During this phase the working group decided to perform an in-depth review of acontrol room facility. Since this was an attempt by the working group to applythe guidance contained in the SRPs, it was believed that this review could pro-vide information and guidance for Phase 3 of this study and would reveal poten-tial weaknesses and oversights in the review process.

The plant selected was an NTOL applicant scheduled for fuel loading in 1984.It was chosen because of its close proximity to a significant number of offsitetoxic gas sources which had been considered in the design of its control room.

The working group spent two days in early January 1984 discussing this plant'scontrol room design and, in doing so, identified a number of questions abouthow the various branches perform their reviews. These questions were added tothe concerns previously identified in Phase 1.

Following the two-day meeting, a list of questions, raised in the course of thereview of the plant by the working group, was drafted and submitted to the appli-cant for the NTOL plant. The questions covered such areas as smoke detection,design temperature and relative humidity of the control room, testing of theisolation dampers, impact of failure of both HVAC systems, handling of toxic-gaschallenges, utilization of the remote shutdown panel, fire-fighting strategy,and habitability parameters Important to reactor operation. These questionsdealt with plant-specific design application and were to be discussed duringthe plant visit.


Subsequently, the plant was visited, systems were inspected, and the questionswere discussed with the plant staff.

2.3 Phase 3

The initial intent of the control room habitability program plan was to reviewthree to five NTOL plants and three to five F-70 plants. This review was todetermine the consistency between the staff's review responsibilities as per-ceived by the working group and actual staff practice. However, it was soondetermined that this task presented some formidable problems. Most of the plants,including the NTOLs, had control room designs which were not based on the pres-ent regulatory guidance. Many plants had been reviewed during a time whencriteria and standards were being revised and documentation that described thebasis for the staff's review was not available. In addition, many of thereviewers who had performed the evaluation were no longer assigned to theresponsible branch. They had been reassigned within NRC or were no longer withthe NRC, so consultations with them were not feasible. Therefore, it was con-cluded that the large expenditures of resources, which would be required tocomplete this task, would not be warranted, considering the possible results.Because of these limitations, it was concluded that it was only practical toaddress present staff review practices.

The second task associated with the NTOL plants and the F-70 plants was to sur-vey the as-built control rooms to determine how NRC design requirements wereimplemented and to determine which component and system tests are performed.

2.3.1 Selection of Plants To Be Surveyed

Although the original program plan called for surveying three to five NTOL plantsand three to five F-70 plants, it was determined that this approach, which wasoriginally broad in nature, should be modified to include fewer plants and tobe conducted in a more comprehensive manner. Therefore, three plants wereselected. Two of the plants had operating reactors, the third was an NTOLapplicant. All three plants were PMRs. The NSSS for one plant was designed byCombustion Engineering and the other two by Westinghouse. The control roomswere designed by Ebasco Services, Inc., Sargent and Lundy, and the utilityowner of the reactor. The three plants selected were chosen in the hope thattheir designs for habitability would reflect the types of control rooms onewould find in the industry for that particular vintage of plant, although thereare no means to readily confirm this.

The NTOL plant was chosen because its design was representative of several NTOLsunder review. The plant is scheduled to receive its operating license in 1985.

2.3.2 Scope of Work of Control Room Survey

Argonne National Laboratories (ANL) was the contractor selected to survey theas-built control rooms. The objective of ANL's work was to review the controlroom habitability design to determine:

(1) the relationship between as-built control room and the system design asdescribed in the FSAR or updated FSAR, and


I (2) what routine operational tests and preoperatlonal tests are performed onvarious control room systems and/or components to ensure design specifica-tions and/or surveillance requirements technical specification require-ments are met, or that the system and/or components are functional.

As a part of this work, ANL was to become familiar with the present controlroom design and habitability requirements and criteria as expressed in standardreview plans, regulatory guides, regulations, and branch technical positions.ANL was to become knowledgeable of the control room design of each plant to besurveyed by reviewing sections of the NRC safety evaluation report (SER) andthe applicant's FSAR or the licensee's updated FSAR which describe varioushabitability aspects of the control room (such as configuration, the HYAC system,the ESF filtration system, fire protection, and protection from toxic gases).On the basis of this review, ANL is to draft a summary of the control roomhabitability design which is applicable to each plant in preparation for ANL'splant visits. At each plant ANL is to survey the as-built control room designfeatures to determine the manner in which the present habitability requirementsand criteria, as described in the NRC SER and the applicant's FSAR or thelicensee's updated FSAR, are implemented. Following the site visit, ANL willprovide the NRC with a summary description of the as-built systems, placingemphasis on identifying differences between the design and as-built systems.The summary will also specifically identify those plant areas that constitutethe control room envelope. ANL will identify the capability of the as-builtplant control room to meet the present control room habitability criteria andthe new proposed control room habitability criteria developed by the workinggroup.

ANL will identify and summarize the tests performed on various control roomsystems and components, including, but not limited to, the preoperationalacceptance test (NTOL) and operational tests, surveillance tests (operatingplants), tests on control room systems and/or components to show functionabil-ity, any preparation or corrective action required on the control room systemsprior to testing, and the duration and frequency of the tests.

ANL will, on the basis of review of these tests, recommend deletions, additions,and modifications on a case-by-case basis. ANL shall also describe actions takenby the licensee as a result of these testing findings.

ANL will identify the location of the emergency shutdown panel(s) and identifyand summarize the procedures for activating the panel(s) and the circumstancesunder which they would be used. ANL will determine the independence of thecontrol room and shutdown panel(s) in terms of HVAC, fire protection, and heatcontrol.

Upon completion of the plant visits, ANL will prepare a report which discussesthe findings and conclusions concerning the following:

(1) differences between the as-built control room and the system design;

(2) tests performed on various control room systems and components including,but not limited to, the preoperational and operational testing of systemsand/or components to assure design specifications and/or technical specifi-cation requirements;


(3) the results of the site visit to each plant;

(4) capability of control room design to meet present NRC habitabilitycriteria and proposed habitability criteria developed by the control roomhabitability working group;

(5) interaction of control room with emergency shutdown facility; and

(6) recommendations for: (a) improving control room habitability design,(b) testing to demonstrate conformance of design, and (c) handlingemergency situations (e.g., toxic-gas or radiation incidents).

Because of the delays associated with obtaining permission from the licenseesfor site visits to review the as-built control rooms and the inability topromptly secure documentaton such as procedures and FSARs or updated FSARsto prepare for these visits, ANL was unable to complete all plant visits beforeJune 1, 1984, and thus meet the original schedule. Therefore, recommendationsand conclusions resulting from these visits are not available at this time.However, the results of ANL's plant reviews will be reported in a supplement tothis report which is scheduled fQr October 1, 1984. It is expected that thecontract work will supplement the findings and recommendations presented inthis report.

During the site visit, ANL will also determine:

(1) the operator's awareness of the availability and completeness of emergencyprocedures in the event of an accident in which toxic gas is released, anaccident involving airborne radioactive material, or a fire in the controlroom;

(2) locations of major effluent release points (building vents) relative tocontrol room air intakes;

(3) operating experiences with toxic-gas monitors;

(4) identification of equipment in the control room that monitors airquality (e.g., C12, CO2. 02);

(5) all sources of heat in the control room that would lead to temperatureincrease during degraded operating modes;

(6) unusual design features that may affect the habitability of the controlroom or interfere with a control room system performing its function;

(7) load calculations which were the basis for the HVAC system design (heating,cooling, dehumidification).

2.4 Support from Office of Research

A research program entitled "Control Room HVAC Equipment Assessment" wasinitated in November 1983 at Sandia National Laboratories in support of thecontrol room habitability program plan. The purpose of the research programis to provide, in its initial stage, an overall review of the guides andstandards utilized in conjunction with control room HYAC design and regulation.


It is anticipated that the research program will address issues raised by theworking group which could not be answered or resolved by the Staff. In orderto better support the working group, Sandia provided a preliminary report onits review of applicable standards, regulations, and specifications. Thiswork involved the review of the HYAC systems for several NTOL plants and hasbeen utilized by the working group in its review. The principal investigator,Mr. Mark Jacobus, participated in the workshop, is taking part in the plantreviews being conducted by ANL, and assisted the working group Project Managerin the early stages of preparing this report.


� a WON-IN WNUAWAWWW� - -1. � 11

CHAPTER 3

DESCRIPTION OF NRR REVIEW PROCESS

The review of control rooms involves seven branches which have input to thestaff's safety evaluation report (SER).

These branches are:

(1) Accident Evaluation Branch (AEB)

(2) Auxiliary Systems Branch (ASS)

(3) Chemical Engineering Branch (CMEB)

(4) Human Factors Engineering Branch (HFEB)

(5) Meteorology and Effluent Treatment Branch (METB)

(6) Radiological Assessment Branch (RAB).

(7) Site Analysis Branch (SAB)

Two other branches, while not having input to the SER, nevertheless interact withfour of the above branches and have significant input to them. These branchesare the Standardization and Special Projects Branch (SSPB) and the QualityAssurance Branch (QAB) who are responsible for the technical specifications ofthe plant and the quality list for equipment and structures, respectively.

There are other branches which may interact with one of the seven branches pro-viding input upon request. These include the:

(1) Emergency Preparedness Licensing Branch (EPLB)

(2) Equipment Qualification Branch (EQB)

(3) Instrumentation and Control Systems Branch (ICSB)

(4) Licensee Qualification Branch (LQB)

(5) Management Analysis Branch (RM/BMA)

(6) Materials Engineering Branch (MTEB)

(7) Mechanical Engineering Branch (MEB)

(8) Power Systems Branch (PSB)

(9) Procedures and Systems Review Branch (PSRB)


(10) Reliability and Risk Assessment Branch (RRAB)

(11) Structural Engineering Branch (SEB)

Figure 3-1 is a block diagram showing the seven branches which have input tothose sections of the SER in which the function of the control room isdescribed. The figure also shows routine interactions which occur as a normalpart of the review process, and non-routine Interactions which occur asrequired. The figure also details where those interactions involve significantinput requirements. The figure illustrates the broad scope of the controlroom habitability review and how successful handling of the subject matter isdependent upon informal Interaction between various branches. Abbreviationsreferenced in control room reviews are listed in Table 3-1.

Appendix B details the review process as it is described in NUREG-0800"Standard Review Plan for the Review of Safety Analysis Reports for NuclearPower Plants." Interfaces between branches are detailed as well as acceptancecriteria. .The primary review responsibility of each of the seven brancheswhich provide input to the SER, is given.


A TehSpc I

- : Require Information InputRoutine Coordination

_-____ : Non-Routine Coordination on"Tornadoes. hurricanes. floods. blizzards. Need Basiseanhquakes. volcanoes

*Providtd on Request

Figure 3-1 Control Room Habitability Block Diagram ShowingBranches, Major Review Areas, and Interfaces


Table 3-1 Abbreviations Referenced inControl Room Reviews

AEB Accident Evaluation BranchASB Auxiliary Systems Bran:hCMEB Chemical Engineering BranchEPLB Emergency Preparedness Licensing BranchEQB Equipment Qualification BranchGDC General Design CriteriaHFEB Human Factors Engineering BranchJCOB Instrumentation and Control Systems Branch

|DIiI IIIL RevieW 8ranchQAB Quality Assurance BranchRAB Radiological Assessment BranchRG Regulatory.GuideRM/BMA Management Analysis BranchRRAB Beliability and Risk Assessment BranchlAO eLi AnalYits BranCh

114 tI HIMYFI 11fi Spoccal ProJect6 Branch


CHAPTER 4

FINDINGS OF THE WORKING GROUP

4.1 Introduction

The recommendations of the working group presented in Section 4.2 were developedthroughout the course of the review. A number of the recommendations addressconcerns originally expressed by the Advisory Committee on Reactor Safeguards(ACRS). Others came out of the workshop, the working group's critique of thereview process, and plant visits.

Appendix A contains the response of the working group to the May 17, 1983 ACRScomments on control room habitability. Since the May 17, 1983 letter, membersof the working group have met several times with the ACRS Subcommittee respon-sible for control room habitability to apprise the Subcommittee of the statusof the review and findings.

4.2 Recommendations

4.2.1 Recommendation 1

The NRR process for conducting the design review of all systems related tocontrol room habitability should be revised. The following changes areproposed:

(1) centralization of description of control room systems into one section ofthe Safety Analysis Report (SAR) through a revision to Regulatory Guide(RG) 1.70 and the designation of a lead branch with the responsibilityfor assuring an integrated review,

(2) utilization of a systems approach in the review rather than the presentmethod, which is dispersed among engineering or scientific disciplinesthat independently perform their review,

(3) utilization of independent verification techniques by branchesresponsible for assessing the adequacy of control room designs.

Discussion

As noted in Chapter 3 and Appendix B, the primary responsibility for thereview of systems and planned operations directly related to control roomhabitability is presently divided among seven branches within the Officeof Nucleir Reactor Regulation. Thirteen other branches are frequently tooccasionally involved in the review of specific areas whenever such a needis identified by a branch having primary responsibility. It is obviousfrom Chapter 3 and Appendix B that control room reviews are fragmented.Sbch fragmentation can lead to inadequate reviews because of omissions,oversights, and Imposition of conflicting requirements.


During the working group's review of staff practices, criteria, andassigned responsibilities related to control room habitability, the memberswere alert to evidence of omission or inadequate review of systems, com-ponents or planned operations which could be attributed to the diffusenature of the review. Considering the large number of branches involvedin these reviews, surprisingly few examples of omission or a breakdown,resulting from oversight, were discovered. However, the working group didnot survey operating reactors to determine whether significant review flawshave been committed which have resulted in inadequate control room designs.Such a survey would be useful. Nevertheless, the working group believesthat the present way in which these evaluations are organized and conductedunnecessarily increases the likelihood of such review faults.

The fragmentation of the Nuclear Regulatory Commission (NRC) review isevident in the SARs which are submitted. NUREG-0800, "Standard ReviewPlan for the Review of Safety Analysis Reports for Nuclear Power Plants,"was prepared for the guidance of staff reviewers in performing safetyreviews of applications to construct or operate nuclear power plants. Theprincipal purpose of the Standard Review Plan (SRP) is to assure thequality and uniformity of staff reviews and to present a well-defined basefrom which to evaluate propoled changes in the scope and requirements ofreviews. It is also a purpose of the SRP to make information about regu-latory matters widely available and to improve communication with inter-ested members of the public and the nuclear power industry and to providethem an understanding of the staff review process.

The safety review is primarily based on the information provided by anapplicant in a SAR. Section 50.34 of 10 CFR 50 of the Commission's regu-lations specifies, in general terms, the information to be supplied in aSAR. The specific information required by the staff for an evaluation ofan application is identified in RG 1.70, "Standard Format and Content ofSafety Analysis Reports for Nuclear Power Plants- LWR Edition." The SRPsections are keyed to the standard format, and the SRP sections are num-bered according to the section numbers in the standard format. Puttingtogether a detailed description of a control room system typically requiresutilization of 13 volumes of an SAR. The working group believes that aseparate section in RG 1.70 devoted to control room habitability, wheredescriptions of control room systems and their interfaces are centralized,would help assure that all significant material related to this subject isconsidered during the staff review. Such an organizational change wouldalso allow the reader to focus on the subject in one section rather thancontinue the current approach in which the descriptions are divided amonga minimum of seven sections.

The lead responsibility for these reviews should be assigned to one branch,either the Accident Evaluation Branch, the Meteorology and Effluent Treat-ment Branch, or the Auxiliary Systems Branch. It is important to recognizethat this assignment will require the reviewers In the designated branchto develop a clear understanding of the control room habitability reviewand the interdependence of the various branch reviews Involved. Additionalpersonnel and fiscal resources will be required for that branch.


Merely assigning one branch overall responsibility for coordinating controlroom habitability reviews does not solve the problem of fragmentation. Itmakes one branch's reviewers cognizant of the total review of controlrooms but allows reviewers in the other branches to continue to performtheir reviews in their usual fashion, i.e. , focusing only on their area ofresponsibility.

One thing that was evident during the working group meetings was that fewmembers were familiar with any SRP dealing with control room habitabilityother than their own branch's. Most reviewers do not see the big picture(total system) but focus only on their area of review which is limited toone system or series of subsystems or components. The working group foundample evidence that reviewers need a broader understanding of the systemsbeing evaluated in order to avoid (1) imposing incompatible or conflictingrequirements, or (2) allowing design modifications without knowledge ofthe impact upon other review areas.

The use of a lead branch will facilitate a more systems-oriented approachto the control room habitability review. The lead branch would coordinatethe review conducted by the-assigned reviewers from each of the brancheshaving a primary responsibility for the subject review. Periodic meetingsof this group of reviewers would allow any problems identified with thesystems to be aireU, anything unique about the design of the systems to bedescribed, etc. This collegial approach initiates the systems interactionapproach more effectively than the present method and expands the breadthof knowledge of the other reviewers. This approach was utilized by theworking group for this study and an obvious broadening of members' know-ledge in the various habitability areas could be seen. The working groupbelieves this approach would not add significantly to the personnel re-sources required for these reviews and could add substantially to the re-viewers' understanding of the overall systems requirements and the adequacyof the systems to fulfill those requirements.

The ACRS expressed concern about the need for a more critical review andindependent assessment by NRC staff members. The working group concludesthat the ACRS concerns appear to be well founded for control room habit-ability. The working group noted a wide variation among branches in theextent to which reviewers attempt to independently verify design adequacy.These reviews may include repeating an applicant's calculations, comparingsystem designs with previously accepted designs, or accepting the appli-cant's commitment to use appropriate guides, standards, or codes. Theworking group recommends a uniform level of review that includes an inde-pendent verification of design adequacy. For some branches, this willinvolve basic and substantial changes in the way they perform reviews.For others, recognition of the need for a more critical review of appli-cant's responses and proposed designs should suffice.


The working group recommends that the staff Increase its efforts in obtainingindustry feedback on control room air cleaning systems through increasedparticipation in professional societies such as ASME and ASTM.


Discussion

Recommendation 6 of this section focuses on increasing the interactionbetween regional inspection and headquarters staff for the purpose ofimproving the quality of reviews and informing headquarters reviewers ofproblems identified by regional inspectors during construction and pre-operational inspections. Another way to increase the quality of reviewsand to become more familar with problems of as-built systems is to obtainindustry feedback. One of the best ways is through participation in var-ious professional societies such as ASME and ASTM. The NRC currently hasan individual on the Committe on Nuclear Air and Gas Treatment (CONAGT) ofASME and on the D 28.04 subcommittee of ASTM. Current NRC practice limitsparticipation to one member per committee. This level of participation isnot sufficient either to receive industry feedback or to provide regulatorypolicy. For example, CONAGT has 29 technical subgroups meeting at leastannually. These subgroups focus on such areas as dampers, ductwork,refrigeration equipment, HEPA filters, fans, structural design--just toname a few. It is impossible for one NRC representative to provide inputto these 29 subgroups, much less attend their meetings. Therefore, theworking group believes that.additional participation in appropriate sub-groups would be beneficial both to CONAGT and to the NRC staff.

It should be noted that it was through participation in CONAGT that thecontrol room habitability workshop was able to gather such an array ofspeakers on short notice. This participation also expedited the processof obtaining utilities willing to allow their control rooms to be surveyed.The working group is grateful for this cooperation.

NRC has historically co-sponsored, with DOE, the biannual Air CleaningConferrence. In the past arrangements have been financed by DOE. Weunderstand that DOE does not plan to finance this program beyond FY 1984.This conference has been of great value to both government and industryfor over 30 years. The NRC should consider sponsoring future conferences.


Control room habitability environmental criteria during the course of an acci-dent should be equivalent to those during normal operation. These environmentalcriteria, as shown in Table C.1-1, Appendix C, should include temperature,relative humidity, ventilation, illumination, visibility, and noise.

Discussion

Human performance is adversely affected by high levels of stress. Stresscan be induced by many factors within the physical, physiological, andpsychological environment of the control room operator and its severity iscumulative across these factors. Some amount of psychological stress isinduced by the presence of an accident condition. The objective of theabove recommendation is to minimize the overall stress load potentialduring the course of an accident by ensuring that the physical and physio-logical environment of the control room does not add to the operator'soverall stress and thus increase the probability of human error. It willalso ensure that, during period of high stress, i.e., an accident, thephysical environment experienced by the operator will be unchanged,familiar, and near optimum for performance and safe operation.



Limiting environmental conditions for operation in the control room should beestablished and should consider human performance as well as equipmentoperation as the basis for selection of appropriate limits.

Discussion

The current technical specification limit for temperature in the controlroom is based on equipment qualification temperatures. If the humanoperator is considered to be an Integral subsystem required for safe plantoperation, then the limiting conditions for operation in the control roomshould be based on the more limiting performer whether it be equipment orhuman. Some of the environmental factors which should be included forconsideration are temperature, noise, and illumination.

Effective temperature (ET) takes into account dry bulb temperature, rela-tive humidity, and air velocity. Air velocity has a minimal effect in thelow ranges expected in a control room (under 100 feet/minute) and can besafely'ignored as a contributor to ET-differences. An effective tempera-ture of 856F has been determined to be the maximum limit for reliablehuman performance. The 85°F (ET) ranges from 85°F dry bulb temaerature at100% relative humidity to 1041F dry bulb temperature at 20% relativehumidity. The working group recommends that a maximum temperature limita-tion of 851F (ET) be established for the control room as the limiting con-dition for operation. If relative humidity is not measured or monitoredin a control room, a dry bulb temperature of 856F should be used as thelimiting condition. This limit should not be exceeded for longer than onehour.

The limiting condition for illumination incident upon the task area shouldbe that which is considered to be minimum for safe manual operation underconditions which have resulted in some degree of normal illumination loss(e.g., loss of AC power). Ten foot-candles, as recommended by the Illumi-nating Engineering Society of North America and as presently adopted bythe NRC staff, is recommended by the working group. This level of illumi-nation is acceptable for periods up to one hour.

Excessive noise not only induces stress but impairs verbal communications,critical to safe control room operations. The noise limits recommended bythe American Conference of Government and Industrial Hygienists are100 dB(A) for no longer than one hour and 85 dB(A) for no longer thaneight hours.

Table C.1-1, Appendix C, of this report contains the habitability criteriaproposed by the working group for inclusion into the plant technicalspecifications.

In developing and proposing limiting conditions for operation, based onhuman performance limitations, careful consideration must be given to theaction statement if these limiting conditions are not met. A questionthat must be answered is whether the preferable action is to maintain thereactor operating or is it to begin the shutdown process with the controlroom operator functioning in a degraded control room environment.


I


The working group recommends that the following generic studies related tocontrol room habitability be conducted:

(1) Evaluation of the adequacy of chlorine and other toxic-gas detectors pre-sently in use at nuclear power plants.

Discussion

On the basis of a review of LERs conducted in 1982, the reliability ofchlorine gas monitors was placed in doubt (see Appendix D). This poorperformance resulted in the release of IE Information Notice No. 83-62.These monitors continue to perform poorly. For this reason, the workinggroup recommends that the reliability of the chlorine and other toxic-gasdetectors be enhanced through identification of improvements in thosedetectors that are "failure prone" or replacement with more reliable moni-tors that are currently available.

(2) Evaluation of the potential.for loss of both trains of the ventilationsystem and its effect on habitability and equipment operability.Consideration should be given to the need for providing guidance tocontrol room operators on appropriate actions in such an event.

Discussion

The ACRS has expressed concern about temperature rise in the event of lossof all air cooling in the control room. The survey of LERs disclosed twoevents in which cooling capability of both trains of the ventilation systemwas lost. In one event, cooling was restored in minutes. For the other,the system was down for 30 minutes, during which time the control roomtemperature rose to 940F. The LER included no information on whether ornot the ventilation system remained in service bringing in outside air,whether temporary ventilation methods were used, or whether considerationwas given to shutting the plant down in the event the cooling system couldnot be returned to service within a relatively short period of time. Theworking group recommended that this event be studied in more detail.

Input from architect engineers indicated that, if both ventilation systemswere lost, the control room would heat up rapidly with estimates in therange of 1-3F0 per minute for the first hour or so. At these heatup ratesthe control room would become uninhabitable.

The proposed study should also consider appropriate actions to be requiredby Technical Specifications in response to loss of one or more trains ofthe ventilation system and possible guidance which could be given to con-trol room operators to decrease heat loads in the control room. By shed-ding heat loads, by opening doors, and by taking other temporary actions,the operators may be able to extend their occupancy time long enough sothat the ventilation system can be restored before the control room becomesuninhabitable.

(3) Determination if sufficient new information is available to justifyrevision of the Murphy-Campe methodology.


I - --- W

Discussion

This methodology is used to estimate atmospheric dispersion in the vicinityof structures through consideration of the locations of effluent releasepoints and air intakes and characteristic building dimensions and meteoro-logical conditions. The need for a study to evaluate the feasibility ofrevising the Murphy-Campe methodology is discussed in Appendix A.

(4) Assessment of the optimum location or locations for toxic-gas monitorsdesignated for the protection of the control room personnel.

Discussion

Toxic-gas monitors are frequently mounted on the exterior of the buildingadjacent to the normal control room air intake. This is not necessarilythe optimum location for such a monitor, and could be of very little valuewhenever the emergency air intake is in use. There is a great variationin the design and proposed manner of operation of control room ventilationsystems. For this reason, a special study is warranted to determine theoptimum location for monitors.

(5) Determination of a minimum purge rate criterion for smoke removal fromthe control rooms.*

Discussion

Although SRP 9.5.1 calls for the capability to purge smoke from the controlroom, no design criterion has been developed. Purge rates varying from4,000 to 45,000 cfm have been found in the systems reviewed during thisstudy. It is clear, for example, that a purge rate of only 4,000 cfm wouldbe of little use in clearing smoke from a 200,000 ft3 control room enve-lope, therefore, some criterion should be established. The working grouphas assumed a minimum of 10 volume changes per hour in Table C.1-1, but adetermination should be made as to whether this value is sufficient topurge the control room.

(6) Development of a method for conducting leakage tests on ventilationsystem isolation dampers.

Discussion

The working group discovered that there is no straightforward method ofmeasuring leakage through the large dampers in the normal ventilationsystem used to isolate the control room. Although a leakage rate may beinferred from measurements taken during control room presuriztion tests,these measurements are of limited value since systems, when operated inrecirculation mode, subject the dampers to a much higher pressure differ-ential than they experience during the isolation test. Thus, the leakagerate could be much higher under these conditions.

in view of the number of problems with dampers, as reported in the LERs,the working group believes this matter warrants additional attention.


(7) Determination of the vulnerability of control rooms to steam intrusion.

Discussion

The ACRS raised the question of steam intrusion. The working group con-cluded that it had insufficient information on control room designs andthe location of high pressure steam lines to assess the potential forsteam intrusion. Although no problems were identified for the systemsthat members of the working group have recently reviewed, designs varymarkedly and the possiblity cannot be ruled out. Hence, further study ofthe matter is recommended.

(8) Assessment of whether the benefits of carpeting in control rooms outweighits potential hazard which can be to emit toxic gases in the event of afire.

Discussion

Carpeting is used in control rooms to help suppress noise and minimizefatigue. Many synthetic materials used in the padding and carpeting areknown to generate large quanitities of toxic gases when exposed to fire.

The working group found conflicting policies existed within two branchesimplementing control room habitability requirements. One branch's policywas that carpeting should not be installed in the control room; the otherbranch's position, however, was that carpeting should be installed.

The toxicity, resulting from fire, of many materials utilized in the con-trol room has been studied. Such toxicity insofar as carpeting and itsassociated padding has not been studied.

Thus, a determination should be made as to whether carpet constitutes ahazard in existing control rooms or whether its benefit for improving theoperator's environment exceeds this hazard.

(9) Effectiveness of fire dampers in limiting the spread of smoke or toxicgases in the event of a fire within the control room envelope.

Discussion

The ACRS expressed concern about the effectiveness of fire dampers inlimitng the spread of smoke and toxic gases. This concern should belimited to a fire within the control room envelope. Fire dampers in theboundary penetrations should always be backed up by one or more isolationdampers.

The working group was unable to assess the need for better smoke controlgenerated by fires within the control room envelope. A thorough study ofthis problem will involve defining temperatures, pressures, smoke, andtoxic gases, conducting a realistic testing program for dampers typical ofthose presently used in control rooms.



There should be more interaction between headquarters and regional personnelduring the OL reviews, especially during preoperational testing. Headquartersstaff should be encouraged to participate in the preoperational inspection ofsystems related to control room habitability.

Discussion

The opportunity to inspect plant systems should substantially increase thecompetency of the headquarters staff, increase the quality of the reviews,and probably minimize conflicts between applicants and staff. An inte-grated review process between headquarters and the regional offices ismore likely to identify differences or inconsistencies between the designreviewed and the as-built system. Also, it will encourage more dialoguebetween regional personnel and headquarters staff, thereby increasing thelikelihood that problems identified in the field will be brought to theattention of the proper reviewer.


The technical specifications involving control room systems should be expandedto include:

(1) habitability criteria such as temperature, illumination, noise, etc.;

(2) acceptable leak rates for isolation dampers;

(3) maximum flow rate for pressurization of the control room;

(4) HVAC system (safety grade); and

(5) corrections to existing technical specifications.

Discussion

The present technical specifications on control rooms are very limited.They only address toxic-gas monitors and ESF filtration units. Habit-ability concerns for humans are not addressed, even though they are morelimiting than the equipment. Inclusion of the above recommended parametersin the technical specifications will provide assurance that the controlrooms will be habitable during off-normal conditions. The technicalspecifications should assure that bottled air supplies are periodicallysurveyed to ensure that air is available and usable and that offsite re-plenishment capability is available; that appropriate limiting conditionsfor operation be specified for Modes S and 6 with both control room ESFfilter systems inoperable; that Generic Letter B3-13 be rescinded to cor-rect errors in the technical specifications covering bypass leakage offiltration units, in-place testing of HEPA filters and charcoal adsorbers,and laboratory tests of charcoal; that surveillance requirements includea~n acceptable leakage rate test for isolation dampers at design pressure;and that the surveillance requirements include a pressurization test stip-ulating maximum ventilation flow rate. Technical specifications shouldalso be added covering safety-grade HVAC systems in the control room.



RGs, SRPs, and other documents such as NUREGs associated with control roomhabitability be revised to bring them up to date with the latest informationand review procedures, is well as with the recommendations of this study.

Discussion

RG 1.52, "Design, Testing and Maintenance Criteria for Post-accidentEngineered-Safety-Feature Atmospheric Cleanup System Air Filtration andAdsorption Units of Light-Water-Cooled Nuclear Power Plants," has beenunder revision for about two years. A number of substantial changes arebeing proposed. A large number nf additional changes were recommended atthe control room habitability workshop in November 1983. The revision hasnot been finalized primarily because of a shortage of personnel resourceswithin NRR. It is recommended that RES utilize the assistance of a con-tractor to complete this task.

Clarification of RG 1.78, "Assumptions for Evaluating the Habitability ofa Nuclear Power Plant Contr9l Room During a Postulated Hazardous ChemicalRelease," is needed as to the manner in which the staff determines allow-able leakage rate for isolation dampers. In addition, inconsistenciesbetween this RG and. RG 1.94 should be eliminated.

The present specifications and acceptance criteria for the control roompressurization test are inadequate. New ones are needed.

SRPs 6.5.1, 9.4.1, and 18.0 should be revised. General Design Criterion60 is not appropriate for SRP 9.4.1 and the definition of control roomenvelope in SRP 9.4.1 is inconsistent with the definition in SRP 6.4.Definitive subsections to SRP 18.0 have not been written, but should be.SRP 6.5.1 should be more explicit.


CHAPTER 5

CONCLUSION

As directed by the EDO the control room habitability working group has reviewedthe subject of control room habitability in such areas as NRR review process,transformation of control room habitability designs to as-built systems, anddetermination of testing protocol. In addition, the working qroup has investi-gated the ACRS concerns and recopiiiendations. The working group has determinedin its review that many of the ACRS concerns and recommendations are wellfounded, and the group has reconmended actions to be taken to address these aswell as other concerns which were raised independent of the ACRS.

The working group has not completed its assignment since the survey of as-builtcontrol rooms and their testing protocol is incomplete. The results of thissurvey will be supplied in a supplement to this report. Nevertheless, thereview of control room habitability has revealed significant areas where theapproach presently utilized in reviews should be altered. These alterationsinclude:

(1) designation of the maintenance of human performance in the control roomto be considered as important as the maintenance of equipment which servesthe control rocm,

(2) centralization of the review of control room habitability so that inter-action between branches becomes commonplace through integrated reviews andthe control room is reviewed as a system and not in a diffuse manner,

(3) provisions to assure that the branches responsible for control roomhabitability reviews independently verify the adequacy of control roomdesigns,

(4) modification to existing technical specifications to increase areascovered and to correct present errors in the specifications,

(5) increased emphasis on interactions between headquarters reviewers andregional inspectors, and,

(6) increased staff participation in professional societies to provide inputon regulatory policy and to obtain industry feedback.


APPENDIX A

CONTROL ROOM HABITABILITY WORKING GROUP (CRHWG)RESPONSES TO ACRS COMMENTS AND RECOMMENDATIONS

ACRS GENERAL COMMENTS

GC-1:

The Subcommittee [ACRSJ continues to be concerned that the reviews and evalua-tions by the NRC Staff of problems associated with control room habitabilityare not centralized. No single NRC group has the responsibility for coordina-tion and integration of such reviews and communication among the groups involvedappear to need improvement. We CACRS Subcommittee3 recommend that one of thegroups involved be assigned the *dministrative and technical responsibilitiesfor coordinating all reviews and evaluations on this subject.

CRHWG Response:

The working group is in complete agreement with the Subcommittee on thiscomment. The primary responsibility for the review of systems and plannedoperations directly related to control room habitability is presentlydivided among seven branches within the Office of Nuclear Reactor Regula-tion. Thirteen other branches are frequently or occasionally involved inthe review of specific areas whenever such a need is identified by a branchhaving primary responsibility. Chapter 3 and Appendix B of the presentreport describe how these reviews are conducted. In addition to the branchreviews, regional offices are responsible for inspecting these systems; theOffice of Inspection and Enforcement prepares inspection modules to guidethe regional offices in their inspection activities.

During the course of its review of staff practices, criteria, and assignedresponsibilities related to the evaluation of control room habitability,the working group was alert to evidence of omission or inadequate reviewof systems, components or planned operations, which could be attributed tothe division of review responsibility among the NRR branches. In consid-eration of the large number of branches involved in these evaluations,surprisingly few examples of omission or a breakdown in review due tooversight were discovered. Nevertheless, the working group believes thatthe way in which these evaluations are organized and conducted unneces-sarily increases the likelihood of such oversights. Thus, it is recom-mended that one branch be assigned the responsibility for coordinating theNRR review of systems and planned operations directly related to controlroom habitability. Section 4.2 contains additional recommendations relatedto staff review practices.

Control Room Habitability Report A-1

GC-2

The NRC Staff members involved appear to be too ready to accept the responsesof applicants and licensees on these matters, rather than assuring themselveson an independent basis that conditions are acceptable. Some of the modelsused by the licensees (for example, those for estimating the rate of temperaturerise in a control room following the loss of the air cooling system) appear tobe supported by insufficient experimental data. The Subcommittee suggests amore aggressive approacn by the NRC Staff in critically' reviewing potentialproblems related to control room habitability.

CRHWG Response

It is the opinion of the working group that the NRC Staff should assure,on an independent basis, that the responses of applicants or licenseesmeet the staff criteria and, if exceptions are taken to these criteria,that the staff independently determines that the exceptions are acceptable.The working group agrees with the ACRS that not all branches have beenindependently verifying the responses of applicants and licensees.

The working group noted a wide variation among branches in the extent towhich reviewers attempt to independently verify design adequacy. Thesereviews vary between repeating the applicant's calculations (in total orspot check), to performing independent calculations, to comparing the de-sign with those which have been previously approved or simply to acceptingthe applicant's commitment to use appropriate guides, standards, or codes.

The working group believes that the staff should Independently verify theresponses provided to them and should utilize a method which will provideconfidence that the approach presented is appropriate and accurate. Forsome branches, this will require basic changes in the way reviews are per-formed. For others, recognition or reinforcement of the need for a morecritical review of applicant responses and proposed designs should suffice.For some branches, this change is likely to require additional personneland fiscal resources.

The working group has recommended that various studies be performed inareas of control room habitability. These areas, which include impact ofthe loss of the control room ventilation system, are enumerated inSection 4.2.5.

GC- 3

The Subcommittee also recommends that the NRC Staff be more aggressive in seek-ing information on equipment failures that might affect control room habitabil-ity. The NRC Regional Office staffs, for example, may be able to obtain dataof interest to the NRC Headquarters regulatory staff. In this regard, effortsare also needed to assure that failures in nuclear power plant safety-relatedheating, ventilating and air conditioning (HYAC) systems are included in theNuclear Plant Reliability Data System (NPRDS) since the Subcommittee understandsthat they will not be Included in the proposed revisions of the NRC LER system.


The reasons that INPO did not agree to provide to the NRC Staff data on HVACsystems developed by consultants to nuclear power plant utilities also need tobe clarified.

CRHWG Response

The NRR staff has explored with Region I the most effective way of obtain-ing information on equipment failures of the type which led to the ACRSrecommendation. It appears that this can best be done during the inspec-tion of radwaste facilities and operations. Region I has implemented suchan effort by directing its inspectors to review reports that testing com-panies submit to the licensees. Inspectors have been instructed to scansuch reports for information relative to corrective actions required onequipment or systems prior to testing in order that they meet specifica-tions. Copies of all significant reports are to be forwarded to NRR.

A memorandum is being sent to IE requesting that the above guidance beincorporated into the radwaste inspection procedure. Suggested changesto IE inspection procedure 50100 which addresses preoperational inspectionof HVAC systems are also being sent to IE.

The working group has held discussions with the Office of Analysis andEvaluation of Operqting Data (AEOD) concering the inclusion of failuresof safety-related RVAC systems in the Nuclear Plant Reliability DataSystem (NPRDS). With regard to the Subcommittee's concern about reportingof safety-related HVAC system failures in the future, the working grouplearned that such systems are not included in the NPRDS. There Is pres-ently no provision for reporting information on NVAC systems or ESF fil-tration systems to INPO. Since there are presently no other means ofobtaining failure data on such systems, NRR is recommending to INPO thatthis omission be corrected.

ACRS SPECIFIC COMMENTS (SC)

SC-1

The formal response by the NRC Staff to our recommendations for a generic dif-fusion study to assist in determining the optimum locatior of alternate air in-takes for control room systems was negative, on the basis that close-in struc-tures and terrain features would invalidate their diffusion models. Yet, atthe Subcommittee meeting, they acknowledged that, in fact, a downwash analysiswould be applicable to this kind of assessment. We agree that such an analysisis generically applicable because of similarities among control room air systemsin standardized nuclear power plants. We therefore recommend that the NRC Staffreevaluate this subject on the basis of the discussions curing the Subcommitteemeeting.

CRHWG Response

Some disagreement exists concerning the usefulness of generic studies,either wind tunnel or in situ, to determine the optimum location of airintakes for control rooms. Many studies have been performed to define


- � -

building wake effects on air flow in the immediate vicinity of largestructures. The results of many of these studies are discussed in somedetail in NUREG/CR-2521, ERL-ARL-1O8, "Method for Estimating Wake Flowand Effluent Dispersion Near Simple Block-Like Buildings" (June 1982), byR. P. Hosker, Jr.

The Atlantic Generating Station (AGS) was modeled in a wind tunnel todetermine the optimum location for the control room intakes for thatfacility. Offshore Power Systems planned to utilize the results of thiswind tunnel study as part of a generic design for other floating nuclearstations. The wind tunnel results for AGS were considered to be directlyapplicable to any other floating nuclear facility because other facilitieswould also be located several miles from shore in open water. Unfortu-nately, the transfer of such data to land-based plants was not as straight-forward because each site is unique with respect to local topography(including terrain and bodies of water) and the shape, configuration, andorientation of major plant structures including cooling towers and otherancillary structures.

Plant-specific studies, either in situ or wind tunnel, have been performedfor a few land-based nuclear facilities, e.g., Rancho Seco and Grand Gulf.Similar studies may be performed for specific design/site configurationsof other facilities to demonstrate compliance with Commission regulationsand requirements. Wind tunnel studies are more likely to be performed thanin situ studies because structures and facilities may be modeled beforetheir construction is complete.

The Staff's methodology to determine the potential radioactivity concen-trations in control rooms following postulated accidents utilizes a down-wash analysis, mentioned at the ACRS Subcommittee meeting, which is de-scribed in "Nuclear Power Plant Control Room Ventilation System Design forMeeting General Criterion 19," by K. G. Murphy and K. M. Campe. Thismethodology hat been compared with the results of in situ and wind tunnelstudies by Hosker (NUREG/CR-2521) and has been found to be conservative.The Staff is continuing to use this methodology unless the applicant candemonstrate, using site-specific data, that other models are appropriate.The staff is proposing to issue a technical assistance contract to compileand examine additional information accumulated since development of Murphy-Campe analysis. Results of this effort will be used to re-assess themodeling of atmospheric dispersion within a complex array of structures.If an improved methodology is identified or developed, it is expected thatit would be incorporated into the Staff's routine review procedures.

Generic studies for optimizing the location of air intakes for controlrooms and to better define the dilution of potential accident-releasedeffluents are of limited value because of the variability of control roomdesigns shape, configuration and orientation of major strucutres, andsite-specific topography. Site-specific studies may be recommended forsome facilities for which the applicant can not demonstrate compliancewith GDC 19 utiliz~ng the Murphy-Campe methodology.


SC- 2

Conditions for human comfort within a control room are based on a maximumacceptable temperature of 1200F. When humidity from human perspiration isadded to a room under these conditions, possibly combined with a low air ex-change rate, the situation could readily become intolerable. Also to be con-sidered is the possibility that the charcoal preheaters in the air recirculatingsystem may contribute an added heat load. The Subcommittee believes that thesefactors should be given careful consideration and that the criterion for tem-perature limits in a control room should be revised, if necessary.

CRHWG Response

The working group agrees that the criteria for temperature limits in thecontrol room should be revised to reflect human performance as a basis.At the present, environmental conditions related to human performance andhuman comfort are not given due consideration in plant technical specifi-cations. The present technical specifications for control rooms includea temperature limitation based upon equipment qualification temperaturesand has been specified as high as 1200F. Since this is also dry bulbtemperature, it does not take into account relative humidity or air flowwhich has a significant effect on humans.

Studies supported by the Department Qf Defense indicate that reliable humanperformance, for short periods of time (up to 8 hours), can be expected inan "effective temperature" (ET) environment up to 85°F (ET) by operatorswearing conventional light clothing and doing light, manual, seated work.Effective temperature takes into account dry bulb temperature, relativehumidity, and air flow. The relationship is shown in Figure A-1, takenfrom MIL-STD-1472C. The ET curve of 850F has been added to the figure toshow the specific conditions related to expected human performance forshort-term operations. The working group recommends that a technicalspecification be established for the control room which allows the maximumtemperature to be 865F dry bulb.

The working group also agrees with ACRS that perspiration and heat addedby charcoal preheaters should be considered in the calculation of heatloads for control room. Although humidity from human perspiration is notexpected to add significantly to the control room's relative humidity,because of the generally large volume of the control room versus the smallnumber of operators occupying it, humidity from any source contributes tothe problem and should be considered. The same is true of any other heatsource contributing to the overall heat load in the control room. Inrecommendation 1 in Chapter 4, the working group recommended that the NRCindependently verify design adequacy.

SC-3

The Subcommittee believes that the NRC Staff needs to develop a protocol fortesting control room NVAC systems. Criteria for acceptance should be based onconditions that permit continuing equipment functionability and human comfort


DRY ULB TEMPERATURE. fC

. 0 .0 20 50 40 50 *0

a, v .' I

' '1 I

' r''''''''I''''''' , '1 '/''''V I V' ' . .r .

OL ggT TOLERACE OT - / SEATED PEMON DOEMD 1 WTWVEJT10uAL

-~CLCYMING Is CWOI DOING LOG"? MANUAL K~9.

2AM M.OTION E*24ALS Pom 12/0 tdI/d.n FOR

o S 41 1 RIM TOLERANCE ZONES ANDS (0 oft t7dO til f 45

_/ COMFORT ZONES AND PERFORMANCE L#MITS.. LMITED TOLERANCE COLD 20NE

Dh40 tR M I N 2 4 12 // 40

b 5 ~~~SUMMR COMFR ZONE* // / / ///

.. -s *a*cS //V / / :a

_ _ Itl~~~~NTEI COMtFORT ZONE */ i/ ///O

* 6b0C oi o 3

o 25

o 02

E

oc L 544UR RELIABLE H"MAN c

11 cc~ PERFORMANCE LIMIT t

55 ET Zs r Z

us 2

WE 4UE TE00WR, de

2 a "o 20

S 0>X5

25

0 '- 20 30 40 so go

DRY BULB TEMPERATURE. 0 C-,.. - - -C -M -C-*Z .C N

S iO is 20

WET BULB TEMPERATURE, PC ..

Figure A-1 Summer and Winter Comfort Zones and Thermal Tolerances

for Inhabited Compartments (MIL-STD-1472C, May 2. 1981)

during prolonged emergency situations. All ports, including dampers, ducts,etc. , should be tested simultaneously as a complete system under both positiveand negative pressures. Particular attention should be given to assure thatsections of such systems that are under negative pressure will not bring incontaminants, which later can gain access to the control room. Possible damageto vital equipment due to pressure surges and disruption of HYAC systems shouldalso be evaluated.

CRWHG Response

The need for and extent of such a testing protocol will be assessed uponcompletion of a technical assistance contract with Argonne NationalLaboratory (ANL).

SC-4

The Subcommittee believes that the quality assurance aspects of HEPA filtermanufacturing, installation and testing need to be given more attention by theNRC Staff. Included in Regulatory Guide 1.52 are references to ANSI N509 andN510 which, in turn, reference the applicable military specifications. TheSubcommittee was told, however, By a representative of one of the filter manu-facturers, that some nuclear power plant operators are purchasing HEPA filtersthat do not meet these specifications. This information should be transmittedto the appropriate NRC Offices (e.g., IE) for further investigation, and cor-rective action should be taken, if needed. The question of whether QualityProduct Listing (QPL) certification is an essential part of the military speci-fications was not clear. The NRC should contact appropriate groups such as theEdgewood Arsenal and the ASME Committee on Nuclear Air and Gas Treatment forclarification of this matter. Relevant information and decisions, as appropri-ate, should be included in the revision of Regulatory Guide 1.52.

CRHWG Response

The working group agrees with ACRS that more attention needs to be givento the quality assurance aspects of manufacturing HEPA filters. Membersof the working group have visited Rocky Flats, which is one of DOE'sfacilities for testing HEPA filters, and have discussed the failure rateof filters that pass through this facility with Rocky Flats testing per-sonnel. In addition, some members of the working group have visited HEPAfilter manufacturers who are and are not on the QPL as well as EdgewoodArsenal, where QPL testing is performed. Both the ASME Committee on NuclearAir and Gas Treatment, who developed the ANSI N509 and ANSI NS10 standards,and the working group agree that being on the QPL is not required for HEPAfilter manufacturers. What the working group maintains is important isthat the filters meet the requirements of MIL-F-51068 as called for inANSI N509. The working group believe that the present requirement forrequalification of HEPA manufacturers every 5 years is insufficient toensure the production of high quality filters and that the requirements ofMIL-F-51068 are met. The working group believes that additional verifica-tion of filter quality is necessary. The manner in which the verificationis performed remains uncertain at this time. It could range from resump-tion of filter testing of all filters at the DOE testing facilities to


random testing of filters to ensure that they meet MIL-STD-51068 to imple-mentation of some other quality assurance tests. It is anticipated thatthe need for additional testing of the HEPA filters will be reflected inRevision 3 to RG 1.52. The working group has recommended that RG 1.52 berevised. The working group is asking IE to issue an information noticewhich emphasizes the requirement that RG 1.52 HEPA filters be installed inappropriate air cleaning systems where such a commitment was previouslymade.

SC-5

The NRC Staff indicated that fire dampers are intended to prevent the spread ofa fire but are not designed or certified to hold back the accompanying smoke orpotentially toxic gases. If this is true, the Subcommittee believes that dataneed to be obtained on allowable leak rates for such dampers and whether thedesign leak rate is achieved in practice. If leak rates are as high as wasindicated by the NRC Staff, are there situations and/or systems in which auxil-iary dampers should be installed to provide supporting seals? Simply to statethat fire dampers "have been proven in industrial operations" is not adquate.Recent reviews of LERs indicate that damper failures frequently occur in nuclearinstallations.

CRHWG Response

The working group is recommending that this question be investigated (seerecommendation 5, Item 9). Fire dampers are installed in fire barrierswhich form the boundaries of fire areas. They are not designed to preventthe spread of smoke or hot gases; however, they do hinder the spread ofsuch gases.

At present, the leakage rates for fire dampers are not specified ortested. The impact of leakage through fire dampers has not been assessedby industry or by the staff. There are three types of leakage that shouldbe considered: (1) leakage through the damper prior to the damper closing;(2) leakage through a closed damper; and (3) leakage through a damper thatmalfunctions and remains open.

The control room emergency zone consists of those spaces that requireoperator occupancy during design-basis events, i.e., control room, computerroom, shift supervisor office, kitchen, and operator locker rooms. Thiszone is serviced by the control room ventilation system. Fire dampers,that are used to prevent fire from entering the control room emergency zonevia the ventilation system, should be located outside of the isolationdampers. Smoke (from fires outside of the control room emergency zone)leaking through the fire dampers would be considered as a tox.ic gas andwould be kept from entering the control room emergency zone by closing theisolation dampers.

Where the control room emergency zone contains other areas, or is connectedto other areas via the control room ventilation systems, a potential existsfor smoke from fires in these other areas to enter the control room by wayof ventilation system ducts. It is not clear that applicants evaluate such


interactions. It does not appear that fire dampers would provide an ade-quate smoke seal, and isolation dampers should be provided at these pointsalso.

The control room emergency zone is usually divided by 1-hr fire barriers.In some cases, fire dampers are provided at these barriers. However, nostudies have been made as to whether the control room emergency zone purgesystems could maintain control room habitability. If not, the controlroom would be evacuated and the plant shut down from the remote shutdownstations.

At present, the Standard Technical Specifications require only periodicvisual inspections of fire dampers. They do not require periodic opera-tional tests. However, some licensees have performed periodic operationaltests and a significant number of instances when fire dampers failed toclose have been reported. The staff is considering whether the STS shouldbe revised and whether such revision should be backfitted.

SC-6

The reasons given by the Staff for rejecting our earlier recommendation thatconsideration be given to increasing the depth of charcoal beds in hnclearadsorption systems are not convincing. Two factors appear relevant to thismatter. First, deeper beds are just as effective for high acute exposures asthey are for chronic low exposures (up to the capacity of the charcoal to retainthe contaminants). As a result, deeper beds are better able than thinner bedsto handle high acute contaminant concentrations. Second, the U.S. philosophythat the control room be sealed rather than be designed to cope with high airintake concentrations will be fully effective only for those plants havingauxiliary compressed air tanks for pressurizing the room; others must take inoutside air to maintain pressurization.

CRHWG Response

The working group agrees that the more charcoal utilized the better thedesign for protecting against toxic gases. The available documentationon the use of deep bed charcoal for protecting control room operatorsagainst toxic gas supports the fact that deep beds are better than thinnerbeds to handle high acute exposures (up to the capacity of the charcoal toretain the contaminants) as well as chronic low exposures. Systems specif-ically designed to use deep bed charcoal filtration would be reviewed bythe staff on a case-by-case basis.

The comment that plants not having auxiliary compressed air tanks forpressurizing the control room and that must take in outside air to main-tain pressurization is not altogether consistent with the currently avail-able documentation on control root designs. Most control rooms are de-signed to be isolated - i.e., not pressurized - following detection oftoxic gas. The limited potential for contaminated outside air to infiltratethrough cracks or other openings is demonstrated by periodic pressurizationtests, as specified in the plant's technical specifications. The workinggroup has recommended that the review of control room include criteria on


the allowable leak rate for isolation dampers and that technical specifi-cations be instituted based upon this leak rate.

SC-7a

The Subcommittee noted that the following problem appears to need evaluationin terms of control room habitability: The impact of the loss of all AC power,of auxiliary services to the chiller systems, of service air, and of componentcooling water.

CRHWG Response

The loss of all AC power will result in the loss of the ventilation systemin the control room. Emergency lighting and shutdown instrumentation willbe available through station batteries. The loss of AC power will alsoreduce the heat load in the control room since the computer, normal light-ing, nonessential instrumentation, and other sources of heat input will belost as well. Because a postulated loss of all AC power is currentlybeyond the design basis, no rigorous evaluation of its affects on the con-trol room environment have been performed. Station blackout is beingstudied generically under Geheric Issue Item A-44. The working grouprecommends that the impact on control room habitability of the loss of ACpower be analyzed Inder this generic issue.

The loss of service or instrument air will not impact the habitability ofthe control room since air-operated valves in safety-related systems suchas the ventilation system in the control room are designed to fail in asafe position (either open or closed) for maintaining system functions.Criteria in this regard are contained in SRP 9.3.1 and are intended toensure that failure of the service air will not prevent safety-re'atedcomponents or systems from performing their safety functions. Valves oritems of equipment that are not designed to fail safe are provided with abackup air supply to maintain their operability on loss of the normal airsystem. It should be noted that most of the valves in safety-relatedsystems in the control room are motor operated.

As in the case of loss of all AC power, a postulated total loss of auxil-iary services to the control room's air conditioning system and total lossof component cooling water is currently beyond the licensing design basesas the safety-related ventilation system in the control room is served byredundant trains of safety-related support systems (service water, com-ponent cooling water, power supplies, etc.). Staff practice continues tobe to assume a single active failure in a safety-related system with anaccident or transient condition. However, input from architect-engineershas indicated that loss of both HVAC systems, regardless of the cause,would result in the rapid heatup of the control room. Estimates rangedfrom 1-3FO per minute for the first hour or so. An event which took placeat Calvert Cliffs resulted in a somewhat lower rate of heatup. Therefore,the impact could be loss of habitabiilty of the control room. The workinggroup has recommended in Recomimendation 5, Item 2, that the Impact of thetotal loss of ventilation system be determined.


i

I

I

SC-7b

The Subcommittee noted that the following problem appears to need careful eval-uation in terms of control room habitability: All potential sources of heatinput in assessing possible temperature increases in degraded operating modes.

CRHWG Response

The working group agrees with the ACRS that all potential sources of heatneed to be evaluated when assessing possible temperature increases duringdegraded operating modes and has recommended that the staff do so. (Seeresponse to SC-2.)

SC-7c

The Subcommittee noted that the following problem appears to need evaluation interms of control room habitability: The potential need for monitoring oxygenconcentrations and steam intrusion.

CRHWG Response

The working group determined that evaluations were performed for the Perryand Byron plants tU determine whether 02 depletion presented a potentialproblem. In these two evaluations no scenario could be identified inwhich 02 depletion was a problem, either in terms of long-term operationin the isolated mode or in terms of depletion due to actuation of a CO2system for fire suppression.

The working group has concluded that it has insufficient information oncontrol room designs and the location of high-pressure steam lines toassess the potential for steam intrusion. Although no problems wereidentified in the systems which members of the working group have recentlyreviewed, designs vary markedly and the possibility cannot be ruled out.Hence, further study of the matter is recommended in Recommendation 5,Item 7.

SC-7d

The Subcommittee noted that the following problem appears to need evaluation interms of control room habitability: Are the current detection limits for con-taminants in the intake air to control rooms sufficient to protect personnel.

CRHWG Response

The toxicity limits of hazardous chemicals most commonly encountered arelisted in Table C-l of Regulatory Guide 1.78. These limits were adaptedfrom Sax's "Dangerous Properties of Industrial Materials" and are con-sidered the maximum concentrations that can be tolerated for two minuteswithout physically incapacitating an average human (i.e., severe coughing,eye burn, or severe skin irritation). Two minutes is considered sufficienttime for a trained operator to don a self-contained breathing apparatus.for those chemicals not listed in Table C-i, the RG 1.78 states that toxi-city limits should be taken from appropriate authoritative sources such as


N�Mll C __ ?--,, . -1, .. I

"Matheson Gas Data Book," "Hygienic Guides Series," "Toxic Substances List,1973 Edition," and "Threshold Limit Values for Chemical Substances andPhysical Agents in the Workroom Environment," listed in the Reference sec-tion at the end of this appendix.

The current guideline on the detection limit for chlorine concentration is5 ppm (specified in Regulatory Guide 1.95). This value is one-third thetoxicity limit of 15 ppm and is associated with Table C-1 of RG 1.95. Thedetection limits for other toxic gases are determined on a case-by-casebasis. The value would depend on estimates of toxic gas concentration asa function of time following release.

The 5-ppm detection limit for chlorine noted above is the concentration atwhich the emergency system will be actuated. This concentration is mea-sured at or near the air intake for the control room ventilation system.With a chlorine concentration of 5 ppm at the air intake and assuming noisolation, the greater part of an hour could pass before the chlorineconcentration within the control room would present a health problem.Thus, the working group concludes that the detection limit for chlorinewas established at a low enough level to assure protection of control roompersonnel.

The staff uses conservatism and a rationale consistent with that used in thechlorine evaluation on the case-by-case assessment of potential hazardspresented by other toxic gases. Thus, the detection limits are consideredto be equally acceptable for the other toxic gases.

The detection limits for radiation monitors in the intake air duct to thecontrol room are provided in the Standard Technical Specifications. Thevalues given vary from less than two times background levels to 5 mr/hr.An immersion dose rate measured within the control room could be one totwo orders of magitude higher than the dose rate measured within an intakeduct due to the volume differences. Thus, the working group considers asetpoint of 5 mr/hr to be too high for this monitor. A new value for thesetpoint is being established. The working groups discovered there wasno branch of NRC assigned the responsibility to review the setpoint forthis monitor to determine whether or not it is sufficient for protectingcontrol room personnel on a plant-specific basis. This oversight has beencorrected by assigning the responsibility to RAS.

References

1. "Matheson Gas Data Book," Fourth Edition, The Matheson Company, Inc., EastRutherford, New Jersey (1966).

2. N. Irving Sax, "Dangerous Properties of Industrial Materials," ThirdEdition, Reinhold Book Corp., New York, New York (1968).

3. *Hygienic Guide Series," published by the American Industrial HygieneAssociation, William E. McCormick, Executive Director, 66 South WillerRoad, Akron, Ohio 44313.


_ _MMnffi� M mill 11 g 1 1 1Enron 1"P1111 it 11 � I I 1PIP11P111 I I � 4� AlI III 111ni,

"-----

4. "Toxic Substances List, 1973 Edition," U.S. Department of Health,Education, and Welfare, National Institute of Occupational Safety andHealth, Rockville, Maryland 20852 (June, 1973). Prepared for NIOSH undercontract by Tracor Jitco, Inc., 1300 East Gude Drive, Rockville, Maryland20852.

5. "Threshold Limit Values for Chemical Substances and Physical Agents inthe Workroom Environment," American Conference of Governmental IndustrialHygienists, Cincinnati, Ohio (1973).


APPENDIX B

CONTROL ROOM REVIEW PROCESS AS DETAILED INNUREG-0800 AND AS ACTUALLY PERFORMED BY NRR BRANCHES

1 ACCIDENT EVALUATION BRANCH (AEB)

1.1 Description of Review As Outlined in the SRP

The AEB reviews the control room habitability systems to determine the adequacy ofthe design to protect the control room operators from the effects of accidentalreleases of toxic gases and radioactive materials. To ensure that this isaccomplished, independent analyses are performed to estimate the radiationdoses and toxic-gas concentrations following design basis accidents (DBAs).The DBA radiological dose guidelines for control room operators are given inthe acceptance criteria of Table.B.1-1. The general acceptance criteria fortoxic gases is also given in this table.

The AEB also examines the areas serviced by the control room emergency ventila-tion system to ascertain that all critical areas for which access is requiredin the event of an accident, are included within the zone and to discourageinclusion of those areas for which access is not required. The control roomemergency zone is to include (1) instrumentation and controls necessary for asafe shutdown of the plant, including the critical document reference file;(2) computer room, if it is used as an integral part of the emergency responseplan; (3) shift supervisor's office; and (4) operator's wash room and kitchen.It is recommended that spaces such as battery room or cable spreading room beexcluded from the emergency zone since they may increase the probability ofsmoke or hazardous gases infiltrating into the emergency zone.

AEB reviews the capacity of the control room, relative to the number of peopleit can accommodate for an extended period of time in an isolated mode beforecarbon dioxide levels become excessive. The carbon dioxide buildup, however,is not normally considered a problem because the air inside a 100,000 cubicfoot control room is normally capable of supporting five persons for at leastsix days.

The primary review guidance used by the AEB in conducting its review is foundin SRP 6.4, "Control Room Habitability Systems." The methodology used forevaluation of toxic-gas hazards in the vicinity of the plant is provided inRG 1.78 and RG 1.95 which are referenced in SRP 6.4. In the calculation ofradiation doses to the control room operators following postulated design-basis accidents, the paper presented by Murphy and Campe at the 13th AEC AirCleaning Conference (reference 6, SRP 6.4) is used. By meeting the guidelinesof SRP 6.4, a control room design also meets the requirements of TMI ActionPlan Item, III.D.3.4 (HUREG-0737).

Secondary reviews are performed by the KETB and SAB, and inputs from thesebranches are used by AEB in its overall evaluation. One METB review area in-volves the determination of the iodine removal efficiency of the control room

Control Room Habitability Report B-1

atmosphere air cleaning system as described in in SRP 6.5.1. These efficienciesare used by AEB in the calculation of control room thyroid dose. The METB alsoprovides meteorological data or, if AEB finds the Murphy-Campe method to be in-appropriate for a particular review and a detailed building-release-receptorrelationship of a facility is needed, the control room X/Q values.

The SAB examines the potential hazardous gas sources in SRP 2.2 and suppliesAEB with descriptions of the hazardous sources and their source strength andprovides their location and estimated concentration levels at the control roomintake.

The acceptance criteria for the control room habitability in the AEB reviewareas are presented in Table 8.1-1. Branches that interface with AEB in thereview of the control room habitability systems are presented in Table 8.1-1.Figure B.l-1 depicts these interfaces.

1.2 Description of Actual Review Process by AEB

In general, the AEB follows the SRP rather explicitly for the review of controlroom systems. Radiation doses to control room personnel are calculated andpotential toxic gas concentrations in the control room are determined. Protec-tive actions for radiation and toxic-gas emergencies are also revleied.

Control Room Habitability Report BUS

Table B.1-1 Summary of AEB Review Responsibilities With Respect toControl Room Habitability As Detailed in the SRPs

I. PRIMARY REVIEW RESPONSIBILITY

Assure that plant operations are adequately protected against the effects ofaccidental releases of toxic gases and radiation materials.

II. ACCEPTANCE CRITERIA

Radiological Doses - GOC 19 of Appendix A to 10 CFR Part 50

5 rem - whole body30 rem - skin or thyroid75 rem - skin with protective clothing

Toxic Gases

No chronic effects from exposure to toxic gases. Acute effects, if any, revers-ible within a short period of time (several minutes) without benefit of anymeasures other than the use of self-contained breathing apparatus. -Concentra-tion at 2 minutes less than protective action limits given in RG 1.78.

Operation

That the plant can be safely operated or shut down under design-basis accidentconditions.

III. INTERFACE

ASS: Evaluates control room ventilation design for single-failure criteriaand other safety requirements in SRP 9.4.1.

CMEB: Provides storage location of CO2 and other firefighting materials.

METB: Evaluates iodine removal of air cleaning unit and provides efficiency,meteorological data, and, upon request, control room X/Q values.

RAB: Determines capability of control room to limit dose to operators dur-ing normal operation to 10 CFR Part 20 levels.

SAB: Identifies potential toxic-gas releases sources and their location,provides estimated hazardous gas concentrations near the controlroom intake and probability of transportation accident-inducedtoxic-gas releases.

SSPB: Cootdinates review of technical specifications

IV. REFERENCE DOCUMENTS

SRP 6:4, "Control Room Habitability System"

GDC 4 "Environmental and missile design bases"


--- ---

Table B.1-1 (Continued)

IV. REFERENCE DOCUMENTS (Continued)

GOC 5 "Sharing of structures, systems, and components"

GDC 19 "Control room"

RG 1.78, "Assumptions for Evaluating the Habitability of a Nuclear Power PlantControl Room During a Postulated Hazardous Chemical Release"

RG 1.95 "Protection of Nuclear Power Plant Control Room Operators Against anAccidental Chlorine Release"

NUREG-0737, "Clarification of TMI Action Plan Requirements", Item III.D.3.4,"Control Room Habitability"

ACCIDENT EVALUATION BRANCH

SAB

Figure 8.1-1 Interaction of AEB With Other Branches in ControlRoom Reviews As Noted in the SRPs


2 AUXILIARY SYSTEMS BRANCH (ASB)


Under SRP Section 9.4.1, ASB reviews the functional capability of the controlroom area ventilation system (CRAVS) to provide a controlled environment forthe comfort and safety of control room personnel and for assuring the operabil-ity of control room components during normal and accident conditions. The re-view includes components such as air intakes, ducts, air conditioning units.filters, blowers, isolation dampers or valves, and exhaust fans. The reviewof the CRAVS covers those plant areas served by the system (within the controlroom envelope) and may includes areas such as the control room, switchgear andbattery room, access control area, control building heating, ventilating, andair conditioning (HVAC) equipment room, and the computer room. The ASB reviewincludes the ability of the CRAYS to deal with the effects of radiation, fires,and toxic chemical releases assuming a coincident loss of offsite power.

ASB reviews safety-related portions of the system to assure that (a) a singleactive failure cannot result in a loss of system functional performance capa-bility, (b) failures of non-seismic Category I equipment or components will notaffect the system's functional performance capability; (c) the control roomheating and cooling subsystems are capable of maintaining a suitablk temperaturefor control room personnel and equipment; (d) the capability exists to detectand filter airborne contaminants inside the control room; (e) provisions existfor the detection and isolation of portions of the system in the event of fires,failures, or malfunctions; and (f) ability of essential equipment serviced bythe CRAVS to function under the worst anticipated degraded CRAVS performances.

ASB also reviews the protection of the CRAVS against flooding, internally andexternally generated missiles, and high- and moderate-energy pipe breaks underSRPs 3.4.1, 3.5.1.1, 3.5.2, and 3.6.1.

As part of the fire protection evaluation under SRP 9.5.1, ASB provides inputto the CMEB regarding the plant's post-fire alternate and safe shutdown capabil-ity. This review includes the capability to achieve a prompt hot shutdown andcold shutdown from outside the control room and independent of control room sys-tems and equipment.

ASB coordinates, as necessary, the reviews by other branches regarding the CRAVS.The branches and the reviews they perform are detailed in Table B.2-1 and aredepicted in Figure 6.2-1.

The acceptance criteria for the control room regarding the functional performancecapability of the CRAYS is presented In Table B.2-1.

2.2 Description of Actual Review Process by ASB

The actual review process followed is very similar to the SRP guidance describedin the previous section. The EQB, however, is not directly involved with thereview. ASB uses the Q-list for its review of equipment qualification. TheQ-list is prepared by QAB with input from EQB.

Control Room Habitability Report B-S

- . _._ _ _ . - - - . . .- - I . 1

Table 8.2-1 Summary of ASB Review Responsibilities With Respectto Control Room Habitability As Detailed in the SRPs


Assure operability of control room components during normal operation, antici-pated transients and design-basis accident conditions and that the control roomarea ventilation system is capable of providing a controlled environment forthe comfort and safety of control room personnel.

Ile AHiANU MUR|HIA

Control room area ventilation system is capable of;

(1) withstanding the effects of earthquakes by meeting the guidelines ofregulatory position C.1 of RU 1.29 for safety-related portions of the sys-tem and regulatory position C.2 of RO 1.29 for non-safety-related portionsof the system In accordance with COC 2.

aMU) maintainin environmental conditions in the control room with)p the design

11MI)M Of fho 94nAtial euipmenlt e6ateld thereWn ftP norma~l IrAnSInt,and accident conditions in accordance with GDC 4.

(3) performing required safety functions as required by GOC 5 for shared systemsand components important to safety.

(4) maintaining a suitable environment in the control room for occupancy duringnormal and accident conditions by meeting the guidelines of regulatorypositions C.3, C.7, and C.14 of RG 1.78 and regulatory positions C.4a andC.4d of RG 1.95 in accordance with GDC 19.

(5) controlling the release of gaseous radioactive effluents to the environmentby meeting the guidelines of regulatory position of C.2 of RG 1.52 andregulatory positions C.1 and C.2 of RG 1.140.

III. INTERFACE

AEB: Reviews the concentrations of airborne contaminants in the vicinityof the intake and exhaust vents resulting from accidental release onplant site and reviews the capability of the system to maintaincontrol room habitability.

CMEB: Receives input from ASB on the plant's post-fire alternate and safeshutdown capability.

EQB: Reviews the seismic qualification of Category I electrical componentsand the environmental qualification of mechanical and electricalcomponents.

ICSB:. Reviews the adequacy of the portion of the protection system used toinitiate operation of engineered safety feature (ESF) system andessential auxiliary supporting systems design, installation, inspec-tion, and testing of essential instrumentation, controls and electri-cal components.


= __


III. INTERFACE (Continued)

MEB: (a) Reviews the system against applicable codes and standards fordesign of components, piping and supporting structures; (b) determinesacceptability of the seismic and quality group classifications forsystem components, and (c) determines adequacy of the inservice testingprogram of pumps and valves.

METB: Reviews the design and effectiveness of the system filters to removeairborne contaminants prior to discharge.

MTEB: Reviews the adequacy of the inservice inspection program for systemcomponents.

PSB: Reviews the onsite power supply sources for safety-related equipment.

SES: Reviews the capability~of seismic Category I structures to withstandthe effects of natural phenomena, e.g., tornado, flood.

SSPB: Coordinates review of technical specifications.


SRP 3.4.1 "Flood Protection"

SRP 3.5.1.1 "Internally Generated Missiles Outside Containment"

SRP 3.5.2 "Structures, Systems, and Components To Be Protected From ExternallyGenerated Missiles"

SRP 3.6.1 "Plant Design for Protection Against Postulated Piping Failures inFluid Systems Outside Contaiment"

SRP 9.4.1, "Control Room Area Ventilation System"

GOC 2 "Design bases for protection agains natural phenomena"


GOC 5 "Sharing of structures, systems, and components"


GOC 60 "Control of releases of radioactive materials to the environment"

RG 1.29, "Seismic Design Classification"

RG 1.52, "Design, Testing and Maintenance Criteria for Atmosphere CleanupSystem Air Filtration and Adsorption Units of Light-Water-CooledNuclear Power Plants"


Table 8.2-1 (Continued)

IV. REFERENCE DOCUMENTS (Continued)

RG 1.78, "Assumptions for Evaluating the Habitability of a Nuclear Power Con-trol Room During a Postulated Hazardous Chemical Release"

RG 1.95, "Protection of Nuclear Power Plant Control Room Operators Against anAccidental Chlorine Release"

RG 1.140, "Design, Testing and Maintenance Criteria for Normal VentilationExhaust System air Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power Plants"

AUXILIARY SYSTEMS BRANCH

PSB

SEB

CSPB

figure B.2-1 Interaction of ASB With Other Branches in ControlRoom Reviews As Noted in the SRPs


3 CHEMICAL ENGINEERING BRANCH (CHEB)


CMEB reviews the fire protection feature:- provided to achieve and maintain safeshutdown conditions. Fire events inside and outside the control room areconsidered.

3.1.1 Fire Events Inside the Control Room

For fire events inside the control room, CMES reviews the plant design toensure that alternate shutdown capability, independent of the control room,is provided.

CMEB determines whether the plant has fire-fighting strategies for the controlroom such as fire brigades, fire extinguishers, automatic fire suppressionsystems, and a hose station. CMEB also assesses the various methods utilizedto separate the control room from the remainder of the plant through the useof fire barriers such as fire dampers, fire doors, and fire-rated penetrantseals. The control room is revilwed to determine whether or not It has a meansfor removing combustion products and whether or not it has smoke detectors incontrol room cabinets, consoles and outside air Intakes.

The location of the outside air intakes is reviewed to ensure that they areremote from the exhaust air outlet for the control room and other areas andfrom smoke vents. Both the outside air intakes, the control room venting orpurging system, and the recirculation portion of the control room ventilationsystem are reviewed to determine whether they have manual isolation dampers.

The construction materials of the control room such as interior walls, floors,ceiling, insulation, sound-proofing, finishing material, equipment, andfurnishings are evaluated for their combustibility.

The acceptance criteria associated with this review is presented in Table 8.3-1along with the interface between branches. Figure B.3-1 also details theseinterfaces.

3.1.2 Fire Events Outside the Control Room

CMEB reviews.the fire protection features outside the control room capable oflimiting fire damage so that one train of systems necessary to achieve andmaintain hot shutdown conditions from either the control room or emergencycontrol station(s) is free of fire damage and that systems necessary to achieveand maintain cold shutdown from either the control room or emergency controlstation(s) can be repaired within 72 hours. The CMEB reviews the fire protec-tion features, i.e. fire detection systems, fire suppression systems, firebarriers, penetration seals including those for ventilation ducts, c&bles,piping and downways; portable blowers for smoke removal, emergency lightingrelated to post-fire shutdown excluding illumination requirements, relativelocation of ventilation intakes and exhausts related to fire hazards; portablefire qxtinguishers, breathing apparatus for fire fighting and post-fire shut-down activities, and interior materials combustibility and smoke generation.


___ . m . . . . . - , - __ p I III I 111111 11P11 - - __ - -- 9T - XU= 1%

Table B.3-1 presents the acceptance criteria associated with this review alongwith the branch interfaces. Figure B.3-1 depicts these interfaces.

3.2 Description of Actual Review Process by CHEB

CMEB performs the review of control rooms with respect to fire protection inthe manner outlined in SRP 9.5.1.

Table 8.3-1 Summary of CMEB Review Responsibility With Respect toControl Room Habitability As Detailed in the SRPs


Review fire protection program to assure, through defense in depth, that a firewill not prevent the performance of necessary plant safe shutdown functions andwill not significantly increase the risk of radioactive releases to theenvironment.


Fire Events Inside Control Room

Provide the reactor with an alternative shutdown capability which is independentof the control room and is adequate to achieve and maintain hot shutdown condi-tions and to achieve cold shutdown conditions within 72 hours without the benefitof offsite power

Provide strategies for fighting control room fires.

Separate control room complex from the remainder of the plant by a 3-hour-ratedfire barrier and seal and protect openings to the control room against fires.

Provide means to remove combustion products from the control room.

Locate fresh air supply intakes for the control room remotely from the exhaustair outlets for the control room and from the exhaust or smoke vent outlets ofother areas.

Provide intakes with a manual isolation damper as well as manual isolation ofthe recirculation portion of the control room ventilation system and the con-trol room venting or purge system.

Provide fixed.self-contained emergency lighting of fluorescent or sealed-beamunits with individual B-hour minimum battery power supplies along with suitablesealed-beam battery-powered portable hand lights for operating personnel.

Provide portable radio communications equipment for operations personnel.


1111-111 I I I lR-M----m-


II. ACCEPTANCE CRITERIA (Continued)

Fire Events Inside Control Room (Continued)

Protect peripheral rooms in the control room complex by automatic suppressionsystems and separate these rooms from the control room by a 1-hour-rated firebarrier.

Protect ventilation systems openings between peripheral rooms and the controlroom by smoke dampers that close on operation of the fire detection or firesuppression system.

Install portable Class A and Class C fire extinguishers in the control room andlocate a hose station outside the control room that is equipped with a nozzlethat satisfies firefighting needs and minimizes physical damage to electricalequipment from the water discharge.

Provide smoke detectors in the control room cabinets, consoles, and outside airintakes of the control room ventilation system.

0

Separate redundant cables in underfloor or ceiling spaces by 3-hour firebarriers and protect individual areas by an automatic fire-suppression system.

Protect enclosed cable raceways more than 1 square foot in area by an automaticfire-suppression system within them.

Interior walls, ceiling, floors, insulation, soundproofing, suspended ceilings,and finished materials are noncombustible.

Fire Events Outside Control Room

Provide fire protection features outside the control room which are capable oflimiting fire damage so that one train of systems, necessary to achieve andmaintain hot shutdown conditions from either the control room or emergencycontrol station(s), is free of fire damage.

Provide systems, necessary to achieve and maintain cold shutdown from eitherthe control room or emergency control station(s), which can be repaired within72 hours.

III. INTERFACE

ASB, RSB, Provides CMEB Identification of systems and components necessary toICSB, PSB provide safe shutdown and the program for identification of location

wfien redundant trains or systems are separated by less than 20 feet.Review system modifications proposed by the applicant to correctseparation deficiencies upon request.

EPLB: Reviews the offsite emergency planning associated with fire events.

Control Room Habitability Report B-1l


III. INTERFACE (Continued)

ICSB: Verifies, upon request, the adequacy of fire protection instrumen-tation and controls.

PTRB: Evaluates plant procedures for fire protection.

QAB: Reviews the quality assurance program for fire protection features.

SEB: Verifies, upon request, acceptability of design analyses, proce-dures, and criteria used for seismic loads resulting from lesssevere natural phenomena.

SSPB: Reviews the technical specifications for fire protection features.


SRP 9.5.1, "Fire Protectioni Prog;am," BTP CMEB 9.5-1, "Guidelines for Fire Pro-tection for Nuclear Power Plants"

GOC 3 "Fire protection"

GDC 5 "Sharing of structures, systems, and components"

RG 1.78, "Assumptions for Evaluating tne Habitability of a Nuclear Power PlantControl Room During a Postulated Hazardous Chemical Release"

RG 1.101, "Emergency Planning for Nuclear Power Plants"

10 CFR Part 50, § 50.48, "Fire Protection"

Appendix R to 10 CFR Part 50, "Fire Protection Program for Nuclear Power Facil-ities Operating Prior to January 1, 1979"


CHEMICAL ENGINEERING BRANCH

EE*11-2FGA Wmmlrn-rn

'EFJ.O/

Figure 0,3- Interaction of CKrB W1th Other Sranche6 in ControlRoom Reviews As Noted in the SRPs.

Control Room Habitability Report E-13

4 HUMAN FACTORS ENGINEERING BRANCH (HFEB)


The HFEB reviews control room habitability for new plant designs as part of thecontrol room design review under SRP 18.0. Operating license applicants andoperating plants are reviewed under Supplement 1 to NUREG-0737, "Requirementsfor Emergency Response Capability." Guidelines for both new and operatingplant reviews are contained in NUREG-0700, "Guidelines for Control Room DesignReviews." Specifically, the following sections of NUREG-0700 are applicableto the habitability aspects of the control room and are reviewed by HFEB.

6.1.4 "Emergency Equipment"6. 1.5 "Environment"6.2. 1.8 "Emergency Communications"6.2.2 "Auditory Signal Systems"Appendix E, "Guidelines for Environmental Measurements"

Section 6.1.4 of NUREG-0700 contains guidelines on the storage, access, training,procedures and need for periodic checks on operator protective equipment andon fire, radiation, and rescue equipment contained in the control room.

Section 6.1.5 of NUREG-0700 contains guidelines on the control room environment,and focuses on system performance for operator comfort in long-term daily opera-tions so that the potential for human error from fatigue or discomfort may beminimized. The guidelines include recommendations on temperature, humidity,ventilation, illumination, audition, decor, and facilities for rest and eating.

Guidelines on emergency voice communications with emphasis on communicationwhile wearing self-contained breathing apparatus, are detailed in Sec-tion 6.2.1.8 of NUREG-0700, and auditory signal systems are discussed inSection 6.2.2. Information is provided on the use and meaning of auditory sig-nals, coding techniques, frequency, and intensity.

Appendix E to NUREG-0700 contains guidelines and sample data sheets for takingenvironmental measurements including sound, lighting, temperature, humidity,and air velocity.

Table B.4-1 presents the acceptance criteria for the human factors review.

4.2 Actual Review Process by HFEB

Definitive subsections of SRP 18.0 have not yet been written. Therefore, pre-sent control room design reviews are conducted using NUREG-0700 as guidance.In the area of control room habitability, NUREG-0700 is generally limited toguidance on conditions for operator performance in normal long-term daily opera-tions to minimize human error. It does not address extreme environmentalconditions.

Supplement 1 to NUREG-0737 requires that the license applicant or licensee sub-mit a&program plan describing how the detailed control room design review (DCRDR)is to be conducted. Based on the adequacy of the plan, the staff determines ifan in-progress audit of the review process is necessary. Usually, this audit


is conducted on site and consists of a review of documentation supporting theOCRDR, discussions with and briefing by the licensee/applicant on review meth-odologies (including environmental surveys), and finally, an audit of the controlroom, simulator, or mockups using NUREG-0700 as the guideline. An audit reportis prepared by the staff and transmitted to the licensee/applicant.

Upon completion of the DCRDR, a summary report is submitted by the licensee/applicant and reviewed by the staff. A determination is made as to the needfor a preimplementation onsite audit by the staff. An SER is prepared by thestaff based on the program plan, in-progress audit (if conducted), summaryreport, and the preimplementation audit (if conducted).

No preoperational or periodic testing is required by either SRP 18.0 or Supple-ment 1 to NUREG-0737.

Table 8.4-1 Summary of HFEB Review Responsibilities With Respectto Control Room Habitability As Detailed in the SRPs


Evaluates control room environment in the areas of temperature, illumination,audition, etc., with respect to their impact on control room operation.


Control room design meets the guidelines of NUREG-0700.

III. INTERFACE

None.


SRP 18.0, "Human Factors Engineering"

Supplement I to NUREG-0737, "Requirements for Emergency Response Capability"(Generic Letter No. 82-33); Section 5," Detailed Control Room Design Review

NUREG-0700, "Guidelines for Control Room Design Reviews"


5 METEOROLOGY AND EFFLUENT TREATMENT BRANCH (METS)


The METS is composed of two sections: the Meteorological Section (MS) and theEffluent Treatment Systems Section (ETSS). Each section reviews the controlroom design and has input into the determination of the habitability of thecontrol room. This input generally Is limited to radiation incidents. However,the MS may provide input for a toxic-gas release which may affect the controlroom.

5.1.1 ETSS Review

The ETSS typically reviews the control room emergency air cleaning system aspart of its review of engineered safety feature (ESF) air cleaning units. Thisreview is conducted under SRP 6.5.1. This SRP addresses the review of all ESFair cleaning units and is not limited to control room systems. The principalpurpose of this review is to determine the appropriate removal efficiencies forthe organic, elemental, and particulate forms of radiolodine that may be pres-ent during and following an accident. These efficiencies are utilized by theAEB reviewer in the calculation of thyroid doses. Whole-body dose Contributionsfrom radiolodine are negligible when compared with dose contributions from noblegases. For the contror room operator, if the doses are less than 30 rem thyroid,the design criterion of GDC 19 is satisfied relative to the thyroid dose. Ifthe applicant can meet the design criterion of GDC 19 without the air cleaningsystem, then no system is required and no review is necessary. However, inmost cases, some removal of radiolodine is required.

SRP 6.5.1 indicates that the plant design should be reviewed to determinewhether an ESF air filtration system is needed. This review is to be coordi-nated with AEB. The SRP also states that a detailed comparison of the aircleaning system design with the acceptance criteria of Section II of SRP 6.5.1is to be made. Designs which are consistent with GDC 19, 61, and 64 and theguidelines of RG 1.52 are assigned the system efficiencies for removal ofelemental and organic forms of iodines given in Table 2 of RG 1.52 and a systemefficiency of 99% for removal of particulates. The air cleaning system is alsoto have the capability to remove fission products based upon a design loadingof 2.5 mg of total iodine (stable plus radioactive) per gram of activatedcharcoal adsorbent.

The common standard, which is referenced for design of the ESF air cleaningunits, is ANSI/ASME N509-1980. Individual components of the systems such asdemisters, heaters, prefilters, HEPA filters, mounting frames, filter housings,adsorbent, fan, ductwork, and dampers are to be designed, constructed, andtested in accordance with the design and qualification testing criteria of thisstandard. The environmental design guidelines for acceptability of the ESF airfiltration unit are based upon the conditions following a design-basis accident(DBA). The radiation source term associated with some of these DBAs is given inRGs 1.3. 1.4, 1.7, and 1.25 and is one of the considerations utilized Inevaluating the control room challenge.

The recommendations of ANSI/ASME N509 and ERDA 76-21 are used to assess thedesign of the system with respect to ease of maintenance and accessibility.


IM MI . .oMOM1 I i__olli'l!

The air cleaning units are required to be redundant and designed to seismicCategory I requirements to qualify as an ESF system.

The testing of the ESF air cleaning unit includes in-place testing of thesystem and laboratory analysis of the carbon adsorbent. Acceptable testingcriteria are presented in ANSI/ASME NS10-1980.

The acceptance criteria of SRP 6.5.1 are presented in Table 6.5-1 along withMETB interfaces with other branches. Figure B.5-1 details these interfaces.

5.1.2 MS Review

The Meteorological Section provides site-specific meteorological information,usually in the form of windspeed factors and wind direction factors based onfrequency of occurrence of these parameters, to enable the AEB reviewer toperform an independent control room dose analysis using the Murphy-Campemethodology referenced in SRP 6.4. The meteorology data for this analysisare reviewed in accordance with the criteria of SRP 2.3.2 and 2.3.3.

If for some reason the Murphy-Caipe approach cannot be used to evaluate theadequacy of the particular control room design, an alternative method mustbe utilized. In this case, MS will provide AEB X/Q values.

MS also provides assistance to AEB on an qi-needed basis for toxic-gas incidentswhich could impact the control room. However this. is not part of the typicalMS review.

5.2 Description of Actual Review Process by NETS

5.2.1 ETSS Review

The NRC reviewer determines, from information contained in Sections 6.4, 6.5.1,9.4.1, and 15 of the FSAR, the conformance of the control room design to theacceptance criteria of SRP 6.5.1 as it applies to the control room emergencyair cleaning system. The applicant also provides a section of the FSAR whichaddresses conformance with the regulatory guides. Exceptions to the regulatorypositions of these guides are noted in the.FSAR. The acceptability of the sys-tem and the capability of the system to perform its intended function, i.e.,mitigate the consequences of a radiation incident on a control room operator,is reviewed taking into account these exceptions.

On the basis of the conformance of the control room emergency air cleaning unitdesign to RG 1.52, the unit will be assigned a removal efficiency from Table 2of RG 1.52 for organic and elemental forms of radiolodine and 99% for par-ticulate forms. These efficiencies are transmitted to AEB for their use incalculating doses to the control room operator.

In most reviews the ETSS only interfaces with two branches, AEB and SSPB. Thestandard technical specifications are provided to the ETSS for the inclusion ofplant-specific parameters by SSPB. Occasionally the ETSS may be required tointerface with other branches based upon the exceptions taken by the applicantto the regulatory positions of RG 1.52. Some of the more likely branches whichcould be requested to provide input and their area of responsibility aredetailed in Table 9.5-1. These interactions are depicted in Figure B.5-1.

eBItPI3 Room Hfifbtflfty kehppt Bait

I

t

5.2.2 MS Review

If the results of AEB's independent dose assessment using the Murphy-Campemethodology and site-specific meteorological information are acceptable, nofurther review is performed by MS. However, if the calculated doses are inexcess of the limits of SRP 6.4, AEB and MS perform a detailed evaluation ofthe applicant's methodology for estimating control room dose. This detailedevaluation may result in: (1) accepting the applicant's approach; (2) requiringfurther substantiation of the acceptability of the applicant's diffusion modelthrough wind tunnel tests or actual dispersion tests conducted at the plant;or (3) requesting the applicant to upgrade the protection system for the controlroom to reduce doses to acceptable levels.

Control Room Habitability Report B-1B

Table B.5-1 Summary of METB Review Responsibilities With Respectto Control Room Habitability As Detailed in the SRPs


Provide efficiency of control room emergency air cleaning unit for removal ofelemental, organic, and particulate forms of rddiododine and site specificwind speed and wind direction factors.


ESF atmospheric cleanup system should conform to the guidelines of RG 1.52, andto the recommendations of ANSI N509, ANSI N510, and ERDA 76-21.

The system should be designed so that: (1) it can operate after a design-basisaccident (OBA) and can retain radioactive material after a DBA; (2) it Isredundant and designed to seismic Category I requirements; and (3) it actuatesautomatically.

III. INTERFACE

AEB: Calculates doses to control room operators following DBAs and, uponrequest, filter loadings of iodine isotopes.

EQB: Reviews the qualification of essential power or electrical controlcables associated with the ESF atmospheric cleanup system (SRP 3.11).

ICSB Reviews instrumentation and control associated with control roomsystems.

MEB: Determines the acceptability of the seismic and quality groupclassification for system components.

PSB: Reviews the associated instrumentation including the power supply andelectrical distribution systems of the control room.

QAB: Performs quality assurance review.

SEB: Determines the acceptability of the design analyses, procedures, andcriteria used to establish the ability of seismic Category I struc-tures housing the system and supporting systems to withstand theeffects of natural phenomena such as the safe shutdown earthquake(SSE),,probable maximum flood (PMF), and tornado missiles.

SSPB: Coordinates review of technical specifications.


SRP 2.2.1-2.2.2 'Identification of Potential Hazards In Site Vicinity"

SRP 2:3.1 "Regional Climatology"

SRP 2.3.2 "Local Climatology"


w ,.-..

f

I

- - - -- - -


IV. REFERENCE DOUMENTS (Continued)

SRP 2.3.3 "Onsite Meteorological Measurements Programs"

SRP 6.4 "Control Room Habitability System"

SRP 6.5.1, "ESF Atmosphere Cleanup System"


GDC 61 "Fuel storage and handling and radioactivity control"

RG 1.52, "Design, Testing, and Maintenance Criteria for PostaccidentEngineered-Safety-Feature Atmospheric Cleanup System Air Filtrationand Adsorption Units of Light-Water-Cooled Nuclear Power Plants"

RG 1.78, "Assumptions for Evaluating the Habitability of a Nuclear Power PlantControl Room During a Postulated Hazardous Chemical Release"

RG 1.95, "Protection of. Nuclear Power Plant Control Room Operators Agalnst anAccidental Chlorine Release"

METEOROLOGY AND EFFLUENT TREATMENT BRANCH

ElYlFigure B.5-1 Interaction of HETB With Other Branches in Control

Room Reviews As Noted in the SRPs

Control Room Habitability Report 01?°

-- --- _ _

6 RADIOLOGICAL ASSESSMENT BRANCH (RAB)


SRP 12.3 addresses the review of the radiation protection features of the plantbut does not specifically detail which plant areas are reviewed such as the con-trol room. The RAB reviewer studies the FSAR and layout drawings of the facilityconcentrating on the sources, shielding, and orientation associated with theauxiliary building. The reviewer assesses the methods utilized to keep occupa-tional exposures ALARA in accordance with 10 CFR § 20.1. The applicant hasestablished maximum radiation dose rate zones. Their acceptability is deter-mined on the basis of the reviewer's assessment that radiation exposure is lessthan 10 CFR Part 20 levels for individuals occupying these zones.

The shielding design of the plant is evaluated with respect to the assumptionsutilized to calculate shield thickness. Ventilation systems are reviewed toensure that they have adequate capability to maintain the concentration ofairborne radioactivity within the requirements of 10 CFR § 20.103. In addi-tion, air cleaning system components should not represent an additional radia-tion hazard. Area radiation monitoring systems are reviewed to ensure thatthey provide protection agalinst exposure to radioactive materials and that theprotection encompasses monitor operation even with loss of offsite power andcapability to handle the anticipated radioactivity during and following anaccident. Airborne radioactivity monitoring systems are evaluated to ensurethat they are located where airborne radioactivity may exist, that the detectorshave sufficient detection capability, are calibrated routinely, and are poweredby emergency power source if offsite power is lost.

RAB reviews the applicant's occupational dose assessment to see that the assump-tions made, the calculations utilized for each radiation zone, the expected andthe design dose rates, and the projected person-rem'doses are documented.Table B.6-1 presents the acceptance criteria associated with RAB's review.There are no branches that interface with RAB.

6.2 Description of Actual Review by RAB

For control room habitability, RAB reviews evidence that radiation protectionaspects are in accordance with applicable regulations to permit occupancy bycontrol room personnel following a LOCA (i.e., GDC 19 exposure limits of 5 remwill not be exceeded). FSAR Chapter 12 normally addresses these criteria interms of facility design features, including assumptions, codes, models, etc.,used in shield design. Additionally, radiation zone designations are classifiedin accordance with occupancy requirements and commensurate radiologicalconditions.

The control room is designed as a zone 1 area (<0.5 mrem/hr) having dose limi-tation requirements of 10 CFR 20 for continuous occupancy during normal opera-tions; as a vital area with dose rates limited to <IS mrem/hr averaged over30 days during an accident, in accordance with KUREG-0737, Item II.B.2; and asan area where adequate radiation protection shall be provided to ensure therequirements of GDC 19.

Thus the major portion of the review by RAB which relates to control roomhabitability is basically twofold. First, RAB ensures that the control room


U

is designed as a zone 1 area. Second, RAB verifies the adequacy of shieldingfor those areas which require low dose rates under all conditions. This reviewincludes verifying that no lines-of-sight exist between areas requiring lowdose rates and potential radioactive sources.

Although SRP 12.3 indicates that RAS does not interface with any other branchin its review, it may interface with AEB on the review of shielding and thecalculation of doses from direct radiation.

Table B.6-1 Summary of RAB Responsibilities With Respect to ControlRoom Habitability As Detailed in the SRPs


Evaluate radiation protection aspects of plant design so that GDC 19 andItem 11.6.2 of NUREG-0737 are met.

II. ACCEPTANCE CRITERIA4

Radiation exposure from normal operation and anticipated transients are keptas low as is reasonably achievable (ALARA).

Maximum radiation zone dose rates, defined for each zone, are classified sothat occupancy during normal operation and anticipated operational occurrencesresults in an annual dose below 10 CFR Part 20 levels to involved individuals.

Acceptable shielding design.

Ventilation system maintains airborne concentration of radioactive materials to10 CFR § 20.103 levels and that air cleaning devices themselves do not re-present an additional radiation hazard.

Area radiation monitoring systems and airborne radioactivity monitoring systemsare present in the appropriate location.

111. INTERFACE

None


SRP 12.3-12.4, "Radiation Protection Design Features"

GDC-19 "Control room"

NUREG-0737, "Clarification of ThI Action Plan Requirements," Item II.B.2,"Plant Shielding"


7 SITE ANALYSIS BRANCH (SAB)


SAB identifies, reviews, and evaluates external events which may threaten thecontrol room operators. These events are limited to non-radiological hazards.The most commonly encountered hazard is the potential release of toxic gaseson or in the vicinity of a site. However, other types of hazards are alsoconsidered.

Accidents attributable to man-made activities can lead to overpressure, missileimpact, and thermal loads. These typically represent an indirect threat sincetheir effects are normally expressed with respect to the control room buildingrather than to the operators. For example, an overpressure from an explosionis a primary hazard with respect to the structural effects on the control roombuilding. Control room operators would be exposed to the secondary effects ifthe overpressure produced internal missiles because of spalling.

SAB evaluates site hazards in terms of threat severity or probability of oc-currence. If a particular hazard is judged to have a significant likelihoodof occurrence, the hazard fs evaluated on a deterministic basis. For example,fixed facilities involving hazardous materials (e.g., flamable or taxic-chemical storage tanks) are generally considered to be a likely source ofhazardous conditions merely by their continuous presence near a site. Thatis, over the lifetime of the plant, the probability of an accidental releasefrom such facilities is judged to be relatively high. Hence, hazards of thistype are evaluated by postulating upper bound accidents and determining thethreat to the control room area, without considering the probabilistic aspectsof the hazard. This constitutes a design-basis approach and the threat isaccommodated through design.

A probabilistic approach is used when the hazard likelihood is perceived to beintrinsically low, so that probabilities become a dominating factor. Forexample, nearby transportation facilities such as railways or highways typi-cally represent an intermittent hazard. The probability of an undue threat tothe control room area is strongly influenced by the shipping frequency of thehazardous materials. Hence, a probabilistic approach is used, wherein shippingfrequencies, accident statistics, and meteorological factors are taken intoaccount when estimating the probability of endangering the control room area.In general, hazards, posed by nearby transportation facilities (i.e., railways,highways, waterways, airways and airports, and pipelines) are first addressedprobabilistically, using SRP 2.2.3 rriteria. If the criteria of SRP 2.2.3 areexceeded, a design-basis approach is taken to reduce the risk to an acceptablelevel.

The primary review guidance used by SAB for site hazards is found in SRPs2.2.1-2.2.3, 3.5.1.5, and 3.5.1.6. When appropriate, RGs 1.70, 1.76, 1.78,1.91, and 1.9S are also used. SRP 2.2.1-2.2.2 provides guidance for identifica-tion of site hazards in terms of location, separation distance, and hazarddescription. SRP 2.2.3 identifies potential accident situations in the vicinityof the plant which can affect the control room and the plant. Site proximitymissiles are reviewed using the guidance of SRP 3.5.1.5. Aircraft hazards arereview in accordance with the guidelines in SRP 3.5.1.6. In some cases, addi-tional review guidance is obtained by requesting technical assistance fromother branches.


When SAB findings indicate that a particular offsite hazard presents an unduerisk to the control room area, the AEB is notified about the need for adesign-basis consideration and is provided a description of the hazard and itssource strength.

Table B.7-1 provides a description of the typical interfaces which occur betweenSAB and other branches. These interactions are depicted in Figure B.7-1.

7.2 Actual Review Processes by SAB

Generally, SAB follows the intent of the SRPs when performing its review.However, it should be noted that in reference to SRP 3.5.1.5, the review oftornado missiles is the primary review responsibility of ASB.

Table B.7-1 Summary of SAB Responsibilities With Respect toControl Room Habitability As Detailed in the SRPs

I. PRIMARY REVIEW RESPONSrBILITY

Evaluate potential explosion, fire, and toxic-gas release accidents in thevicinity of plant. Identify potential external hazards or hazardous materialswhich are present or which may be reasonably expected to be present during theexpected lifetime of the plant and whether these hazards have the potential forgenerating a missile which could adversely affect structures, systems and compo-nents essential to safety. Determine the capability of the structures, systems,and components to withstand missiles. Identify potential offsite accidentsthat could affect control room habitability.


Plant is adequately protected and can operate with an acceptable degree ofsafety when the presence of hazardous materials or activities at nearby indus-trial, military, and transportation facilities is considered (10 CFR Part 100.10)

Structures, systems, and components important to safety are appropriately pro-tected against the effects of missiles that may result from offsite events inaccordance with GDC 4.

III. INTERFACE

AEB: Reviews control room habitability with respect to toxic chemicalssources identified by SAB.

ASB: Evaluates possible effects of thermal, missile and overpressure onplant structures.

RM/BMA: Reviews probability analyses of potential accidents involvinghazardous materials or activities in the vicinity of the plant.

SEB: Evaluates possible effects of external events such as explosionsand missile on plant structures.




SRP 2.2.1-2.2.2, "Identification of Potential Hazards in Site Vicinity"

SRP 2.2.3. "Evaluation of Potential Accidents"

SRP 3.5.1.5, "Site Proximity Missiles (Except Aircraft)"

SRP 3.5.1.6 "Aircraft Hazard"


RG 1.70, "Standard Format and Content of Safety Analysis Reports for NuclearPower Plants"

RG 1.76, "Design-Basis Tornado for Nuclear Power Plants"

RG 1.78, "Assumptions for Evaluating the Habitability of a Nuclear Power PlantControl Room During a Postulated Hazardous Chemical Releate"

RG 1.91, "Evaluation of Explosions Postulated to Occur on Transportation RoutesNear Nuclear Power Plant Sites"

RG 1.95, "Protection of Nuclear Power Plant Control Room Operators Against anAccidental Chlorine Release"


SITE ANALYSIS BRANCH

Figure B.7-1 Interaction of SAB With Other Branches in ControlRoom Reviews As Noted in the SRPs


APPENDIX C

PROPOSED CONTROL ROOM HABITABILITY CRITERIA

Table C-I presents the various habitability parameters for control rooms andthe present NRC habitability criteria associated with each. The referencedocuments from which these criteria were obtained are also listed in the table.The following sections discuss the working group's assessment of the presenthabitability criteria.

1.1 Temperature and Relative Humidity

Item 6.1.5.1 of NUREG-0700 "Guidelines for Control Room Design Review," Indi-cates that the HVAC for a control room should be capable of maintaining tempera-ture and relative humidity within the comfort zone of Exhibit 6.1-21 ofNUREG-0700. The temperature range for this zone is 730F to 78°F with a rangein relative humidity of 20% to 60%. These criteria are based upon the ASHRAEcomfort standard 55-74. HUREG-0700 has as another criterion that the differencein air temperature between floor level and head level should not exceed 10F.

The NRC presently has no criteria for temperature and relative humidity appli-cable to operation with the HVAC system in a degraded mode. Failure to havesuch criteria has been attributed to the requirement for redundant HVAC trainto be safety grade and each capable of maintaining the temperature and rela-tive humidity within normal operating limits. Architect-engineering firmshave estimated that if both HVAC systems are lost, the temperature would riseat a rate of 1&3F0 per minute for an hour or sto maki the eone rl room unifthAPI&IAPI, lOVIgW Of Iffs dI6gif*d4 One event in whu ath ELF cOnditiOningunits were out of service trr a period of 30 mn. The control room temperaturerose to a level of 9401# a rate of about 1/I92/2f per minut.o

In view of the relatively large number of failures of control room air condi-tioning systems reported in LERs and the simultaneous loss of redundant units onat least two occasions, the working group concluded that temperature and rela-tive humidity criteria should be established for operation with the HVAC systemin a degraded mode.

An effective temperature of 85'F.has been determined to be the maximum limitfor reliable human performance.* Effective temperature (ET) takes Into accountdry bulb temperature, relative humidity, and air velocity. With an air velocityof 0-30 feet/minute the 85°F (ET) ranges from 850F dry bulb temperature at 100%relative humidity to 1040F dry bulb temperature at 20% relative humidity. Airvelocity has a minimal effect on the low ranges expected in a control room(under 100 feit/minute) and can be safely ignored as a contributor to effectivetemperature differences. Since relative humidity is not normally measured

*Reference - NIL STD-1472C, NIL HDBK-759A.

Control Room Habitability Report C-1

or monitored in a control room, a worst-case condition can be assumed and a drybulb temperature of 85F can be used as the limiting condition. This limitshould be exceeded for no longer than one hour.

1.2 Ventilation

The working group had previously determined that ventilation was important tomaintaining a habitable control room and to maintaining the control room opera-tor in an alert status. Item 6.1.5.2 of NUREG-0700, has guidelines for venti-lation. These guidelines involve air quantity and air velocity. The require-ments of HUREO-0700 are a minimum intake of outdoor air of 15 cfm per occupantand an air velocity of less than 45 ft/min when measured at head level. Inaddition the air velocity should not produce a noticeable draft,

The working group investigated other possible requirements for ventilation,and concluded that the guidelines cnntained within NUREG-0700 are acceptable.

1.3 Radiological Dose

The present limitation for radiological doses to control room operators includeboth normal operating situations and accident conditions. For normal opera-tion, direct exposure limits are established by 10 CFR § 20.101. Ifihalationlimits are established by 10 CFR § 20.103. The allowable airborne radio-activity concentrations for normal operations are given in Table I, Column 1 ofAppendix B to 10 CFR Part 20 for occupational workers. The working group con-sidered these levels acceptable for normal operating conditions.

General Design Criterion (GDC) 19 of Appendix A to 10 CFR Part 50 establisheswhole-body dose limitations for control room operators during accident condi-tions. Inhalation dose to the thyroid is derived through an expansion of thecriterion of GDC 19 and the external skin dose is also derived through suchan expansion. The working group considered the existing limits acceptable.

1.4 Communications

The present criteria for communications in the control room are given in Sec-tion 6.2 of NUREG-0700 and state that voice shall be the means of communica-tion. The working group saw no reason for change. However, one cannot dis-associate communications from the consideration of noise. Noise limitationsare discussed Section 1.7 of this appendix.

1.5 Visibility

The present requirement for visibility in the control room is that it be un-limited. One of the problems associated with this requirement is the capabil-ity to test it during off-normal situations. The visibility in the controlroom may be affected by smoke from a fire or by infiltration of a toxic-gasplume or by placement of control panels.

The working group observed that the present control room designs had purge fanswith 4 capacity rating which ranged from 4,000-45,000 cfm. At the lower end ofthis spectrum, these fans are not of sufficient capacity to be capable of effi-ciently removing either smoke or a toxic gas from the control room. Therefore,


_I

it was the working group's assessment that criteria needed to be developed forremoval of smoke and toxic gases from the control room. The working group arbi-trarily selected ten volume changes per hour as a possible acceptable purgingrate for in Table C-i but recommended in Recommendation 5, Item 5, of thisreport that a determination be made whether this value is sufficient to purgethe control room.

1.6 Illumination

Exhibit 6.1-22 of NUREG-0700 contains the present, recommended illuminationlevels for various control room work areas and types of tasks. These levelsinclude the minimum, the maximum, and the recommended values.

The levels of emergency operating lighting are allowed to decrease underdegraded conditions to as low as 10 footcandles, with 5 being the value forevacuation paths. For all other occurrences the lighting levels are expectedto remain within the acceptable range of Exhibit 6.1.22.

The present criteria for illumination also include preferred reflectance valuesand permissible reflectance levels for various surfaces. The working groupconcluded that the present reflectance levels are acceptable.

1.7 Noise -

The present control room requirement for noise is that the background noiseshould not impair verbal communications between any two points in the primaryoperating area. A limit of 65 decibels (dB) has been established. Exhibit 6.1-26 of NUREG-0700 states that this level allows normal voice communication up toa distance of 4 feet.

The military recommends in MIL-STD-1472 and MIL-STD-1474 an upper limit fornoise of 65 dB for operation centers, mobile command and communication centers,computer rocms, word processing centers, kitchens, and laundries. This allowsfrequent telephone use and frequent direct communication at distances up to5 feet.

On the basis of the working group's review of the data, the group recommendedthat allowable noise level of 65 4B be retained.

1.8 Chemical Contaminants

Table C-1 of Regulatory Guide 1.78 provides the maximum allowable 2-minute con-centration of various toxic gases. These limits were adapted from Sax's"Dangerous Properties of Industrial Materials" and are considered the maximumconcentrations that can be tolerated for two minutes without physicallyincapacitating an average human (i.e., severe coughing, eye burn, or severeskin irritation). Two minutes is considered sufficient time for a trainedoperator to don a self-contained breathing apparatus. For those chemicals notlisted in Table C-1, RG 1.78 states that toxicity limits should be takenfrom appropriate authoritative sources such as "Matheson Gas Data Book,"Hygienic Guides Series," "Toxic Substances List, 1973 Edition," and "ThresholdLimit Values for Chemical Substances and Physical Agents in the WorkroomEnvironment" listed in the References section at the end of this appendix.


-,_-______-__ 11

The current guideline on the detection limit for chlorine concentration is5 ppm (specified in Regulatory Guide 1.95). This value is one-third thetoxicity limit of 15 ppm and is associated with Table C-1 of RG 1.95. Thedetection limits for other toxic gases are determined on a case-by-casebasis. The value would depend on estimates of toxic gas concentration asa function of time following release.

The 5-ppm detection limit for chlorine noted above is the concentration atwhich the emergency system will be actuated. This concentration is meas-ured at or near the air intake for the control room ventilation system.With a chlorine concentration of 5 ppm at the air intake and assuming noisolation, the greater part of an hour could pass before the chlorine concen-tration within the control room would present a health problem. Thus, theworking group concludes that the detection limit for chlorine was establishedat a low enough level to assure protection of control room personnel.

The staff uses conservatism and a rationale consistent with that used in thechlorine evaluation on the case-by-case assessment of potential hazards pre-sented by other toxic gases. Thus, the detection limits are considered to beequally acceptable for the other toxic gases. Therefore, the working groupconsidered the values in Table C1 of RG 1.78 acceptable.

References

1. "Matheson Gas Data Book," Fourth Edition, the Matheson Company, Inc., EastRutherford, New Jersey (1966).

2. N. Irving Sax, "Dangerous Properties of Industrial Materials," ThirdEdition, Reinhold Book Corp., New York, New York (1968).

3. "Hygienic Guide Series," published by the American Industrial HygieneAssociation, William E. McCormick, Executive Director, 66 South WillerRoad, Akron, Ohio 44313.

4. "Toxic Substances List, 1973 Edition," U.S. Department of Health,Education, and Welfare, National Institute of Occupational Safety andHealth. Rockville, Maryland 20852 (June 1973). Prepared for NIOSH undercontract by Tracor Jitco, Inc., 1300 East Gude Drive. Rockville, Maryland20852.

5. "Threshold Limit Values for Chemical Substances and Physical Agents inthe Workroom Environment," American Conference of Government IndustrialHygienists, Cincinnati, Ohio (1973).


www'. . - - - - - .- - ___- .10IP �M

Table C-i Proposed Control Room Habitability Criteria

Parameter Proposed Criteria Source

A. TEMPERATURE AND RELATIVEHUMIDITY

Floor Level to Head Level AT

T (°F)

RH (X)

Maximum Allowable Temperature(f) for 1-hour

10F

73 < T c 78

20 < RH < 60

85(*)

NUREG-0700, 6.1.5.1

NUREG-0700,

Exhibit 6.1-21

MIL-STD-1472 CMIL-HDBK-759 A

B. VENTILATION

I. Makeup Air (Outside)

Per Occupant

II. Air Velocity

15cfu

<45fpm

NUREG-0700, 6.1.5.2

NUREG-0700, 6.1.5.2

C. RADIOLOGICAL DOSE IREM)

I. Direct Exposure

a. Normal Operation

Whole Body(**)

Forearms, Hands

Skin

b. Accident

Whole body

Skin

(Per quarter)

1.25 rem

18.75 rem

7.5 rem

5 rem y

75 rem p (withprotectiveclothing);30 rem p (with-out protectiveclothing

10 CFR 20.101

10 CFR 20.101

10 CFR 20.101

GDC 19 ofAppendix A to10 CFR Part 50

GDC 19 ofAppendix A to10 CFR Part 50

II. Inhalation

a. Normal Operation

b. Accident

Table I, Column 1,10 CFR 20.103Appendix B to10 CFR Part 20

30 rem thyroid

10 CFR 20.103

Application ofGDC 19

See footnotes at end of table.

Control Room Habitability Report C-S

�M_ - --

M -

Table C-1 (Continued)


D. COM*UNICATIONS Voice NUREG-0700,pg 6.1.4

E. VISIBILITY Unlimited pluspurge fan capabil-ity of 10 volumechanges per hour.(*)

F. ILLUMINATION

Panels, Auxiliary(t)Panels, ScaleIndicator Reading,Printed or Typed ReadingMaintenance and WiringAreas (foot-candles).

Seated Operator Stations(t)Handwritten ReadingWriting and Recording

(foot-candles)

Reflectance

20 < I < 50

50 < I < 100

NUREG-0700,Exhibit 6.1.22

HUREG-0700,Exhibit 6.1.22

HUREG-0700,Exhibit 6.1.24

Ceiling

Upper Wall

Lower Wall

Instruments/Displays

Cabinet/Consoles

Floor

Furniture

G. NOISE

Background dB(A)

60% <

40% <

15% <

80% <

20% <

15% <

25% <

R <

R <

R <

R <

R c

R<c

R <

95%

60%

20%

100%

40%

30%

45%

c65 NUREG-0700,Curve 6.1-26

See footnotes at ond of table.


Table C-i (Continued)


H. CHEMICAL CONTAMINANTS RG 1.78, Table C-1

(2 minute)(tt)

CO2 1. 0OCO 0.LI02Cl2 15Acetaldehyde 200Acetone 2000Acrylonitrlle 40Anhydrous NH3 100Aniline 10Benzene 50Butadiene 0.LXButenes AsphyxiantEthyl chloride 10.000Ethyl ether 0ooEthylene dichloride 100Ethylene oxide 2Q0Fluoride 2Formaldehyde 10He AsphyxiantHydrogen cyanide 20H2S 500Methanol 400N2 AsphyxiantNa2O 2(0)SO2 5H2SO4 2(#)Vinyl chloride 1000Xylene 400

*Criteria are not presently Implemented by NRC reviews.

"*Limited to 3 rem maximum per quarter, provided 3 rem whole-body plus pastaccumulated whole-body dose not exceed 5 (N-18) rem where N = age ofindividual.

tIllumination levels are allowed to decrease to 10 foot-candles for eventinitiating a loss of illumination such as a loss of AC power event(5 foot-candles for an evacuation path).

ttParts of vapor or gas per 106 parts air by volume at 250C and 760 um Hg.

#Milligrams of particulate per ms of air at 25'C and 760 mm Hg.


APPENDIX D

FAILURE RATE OF EQUIPMENT AFFECTING CONTROL ROOM HABITABILITY

I lVAC SYSTEM LERs

The working group obtained a printout of License Event Reports (LERs) associatedwith the control room air conditioning and ventilation system (CRAVS) reportedOctober 1977 - December 1983. This printout included 432 LERs. Table D.1-1shows a breakdown of these LERs sorted into categories to identify the failedcomponent or the sources of the failure. Some LERs fit into more than onecategory, bringing the total category count to 494 from the 432 LERs.

The working group analyzed these categories and characterized the major causeswithin the larger categories as follows:

(1) Dampers/Valves (Including Operators) - 102 LERs - 24% of total LERs

Most of the LERs (80-90%) associated with this category involve air flowdampers. The remaining LERs are associated with freon or damper hydraulic con-trol valves. The reported damper failures were about 75% mechanical or admini-strative in nature - loose or stuck linkages, failed actuating cylinders, looseset screws, dampers left in wrong position following maintenance - and the re-maining 25% were of an electrical nature - mostly control failures with somepower failures (blown fuses).

(2) Chlorine Gas Monitors - 55 LERs - 13% of total LERs

The total number of inoperative monitors actually exceeded the 55 LERs pre-sented here since, in many instances, more than one monitor was affected by thesame cause(s). The major causes reported were dirty or clogged electrolytewicks and clogged electrolyte orifices. These two factors approached being acommon-cause failure, since they often resulted in more than one monitor beingInoperative or out of calibration. Other problems associated with these moni-tors were air sampler fan failures and improperly installed recording tape.

(3) Blowers/Fans Air Conditioners - 78 LERs - 18% of total LERs

This category included 30 failures associated with air conditioning systems.The reported causes of blower/fan failures were pretty evenly divided betweenmechanical (worn/broken drive belts, motor bearings, loose set screws) andelectrical (breaker thermal overloads and control switch malfunctions). Oneevent involved the loss of both air conditioning units for a period of30 minutes. 1he temperature rose to 940F.

(4) Control Switches - 37 LERs,- 8.6% of total LERs

Control switches monitor air flow, temperature, and humidity and, in turn,control blowers, dampers, compressors, and pumps. There is overlap betweenthe LERs listed in this category and those listed under blowers and dampers.

Control Room Habitability Report D-1

Table D.1-1 Control Room Air Conditioning and VentilationSystem LERs (October 1977 - December 1983)

Number (%)

Category

Dampers/Valves (Including Operators)

Chlorine Gas Monitors

Blowers/Fans/Air Conditioners

Control Switches (Flow, Temp, Humidity)

Radiation Monitors

Administrative Controls, Maintenance andTest Procedures Error, Operator Error

Charcoal Fllter/Adsorbers

Control Room Door/Dampei Seals

Air Bottles

Ammonia, Other Gas Monitors

Temperature sensor/alarm (No Control Function)

Miscellaneous (Not in Above Categories -Design/Installation, Heaters, LooseElectrical Connection)

Number (%)of total LERs

102 ( 2 4%)*

55 (13%)

78 (18%)

37 (8.6%)

29 (6.7%)

47 (11%)

29

24

6

9

5

73

(6.7%)

(5.6%)

(1.4%)

(2.1%)

(1.2%)

(17%)

Total 494

*The total of the percentages exceeds 100% because of the LERs that fit intomore than one category.

Control Room Habitability Report O-2

(5) Radiation Monitors - 29 LERs - 6.7% of total LERs

Most of these LERs involved setpoint drift. There were some instances ofclogged suction filters.

(6) Administrative Controls, Maintenance and Test Procedure Error, OperatorError - 47 LERs - 13X of total LERs

These occurrences were usually the result of one train failing to pass a sur-veillance test while the redundant train was out of service for maintenance.In all cases except one, when redundant trains were temporarily inoperativeonly the normal or the emergency ventilation system was affected - not bothsystems. The inoperative trains were restored to service within the planttechnical specification time limit or a plant shutdown was initiated except forone instance in which the redundant trains of both the normal and emergencyventilation systems were inoperative simultaneously. This instance involveda combination of equipment failure and operator error. The plant was at0% power at the time of this incident.

Two notable maintenance/test procedure errors were

(a) The control room and computer room smoke detectors were removed formaintenance and not reinstalled for 13 months.

(b) The control room air flow verification tests were omitted for 3 years.

(7) Charcoal Filter/Adsorbers - 29 LERs - 6.7% of total LERs

These LERs involved either laboratory analysis of charcoal showing low charcoalefficiency or failure to properly fill charcoal test canisters. No LERs werereported involving HEPA filters.

Most of the above LERs were generated during or as a result of plant technicalspecification surveillance testing. There were no LERs on self-contained airbreathing apparatus, since it is not covered by plant technical specifica-tions.

Several of the LERs illustrated significant points which should be covered inthe review process. First, two LERs concerned problems with the interpretationof RG 1.52 at Three Mile Island 2 and Farley 2. Three Mile Island 2 had beenlaboratory testing charcoal adsorber material to an acceptance criterion of99%. According to the report, the plant technical specifications referencedRG 1.52, Rev. 2, which specifies acceptance criteria for relative humidity con-trolled systems. Since Three Mile Island 2 has no relative humidity controlledsystems, THI staff claimed that none of the tests applied. TMI staff revisedits test procedure using the 'assigned" efficiency of 95% from RG 1.52 insteadof the laboratory penetration efficiency of 99%. At Farley 1, a similar pro-blem with the interpretation of RG 1.52 resulted in action exactly opposite tothat of Three Mile Island. Farley had been testing to a removal efficiency of95%, but decided that 99% was the correct criterion based on RG 1.52, Rev. 2.


At Brunswick 2, it was determined that the air cleaning system trains would notisolate upon receipt of a chlorine isolation signal if the system controlswitch was in the "on" position. The system was run in this configuration forabout one week until It was discovered that while in the "on" position thechlorine contacts were bypassed. A related problem at Brunswick 2 was thatthe two isolation dampers in the ventilation system did not receive a "close"signal upon detection of chlorine.

At McGuire 1 it was discovered that the diesel generator exhaust was enteringthe technical support center through the ventilation system. The intake ductwas to be relocated away from the diesel exhaust.

A Susquehanna 1, it was observed that the chlorine detectors on the controlroom emergency outside air supply could prevent operation of the system in thepressurization mode following the loss of power. If such an event occurred thecontrol room could not be maintained at a positive pressure to limit radiationexposure of control room personnel during certain accident conditions.

2 FIRE PROTECTION LERs

LERs for fire protections systems for the control room emergency zone wereobtained for the period from approximately January, 1981 through Oelember, 1983.In total, 66 LERs were categorized. The LERs which fit into more than onecategory caused the total in the categories to be 75. The major failures en-countered included breached fire barriers, administrative and procedural con-trol errors, and failed detectors and annunciators.

Two potentially significant events were identified that could be covered moreadequately in the review and inspection processes. One event which was Identi-fled was that a fire protection system alarm could go undetected if it occurredafter another fire protection system alarm. The detection of the second alarmcould be delayed by a significant period of time because the annunciator inthe control room was not provided with a reflash capability. The only indica-tion of the problem would occur at a secondary panel located out of the sightof operators.

The second event involved a fire damper which was never installed in the controlroom ventilation system. Table D.2-1 presents a listing of the LERs associatedwith fire protection in the control room.


Table D.2-1 LERs Involving Fire Protection in Control RoomEmergency Zone (January 1981 - December 1983)

CategoryNumber (X)of total LERs

Annunciators

Detectors

Seals, Doors, Barriers, Dampers

Administrative Controls, Maintenance andTest Procedures, Error, Operator Error

Misc., Sprinkler System Components, Valves,Relays, Headers

7 (1I%)*

11 (17%)

32 (48%)

20 (30%)

5 (7.6%)

Total 75

*Ihe total of the percentages exceeds 100% because of the LERs that' fit intomore than one category.


APPENDIX E

NRC INSPECTION ACTIVITIES ASSOCIATED WITH CONTROL ROOM HABITABILITY

1 INTRODUCTION

There are a number of IE inspection modules that provide the regional staffswith guidance for inspecting ventilation systems. Different types of aircleaning and ventilation systems are used in nuclear power stations and gener-ally vary in size and design from one station to the next. Because of thesedifferences, the guidance provided in the inspection modules is of a generalnature and does not specifically deal with individual types of systems, suchas the control room ventilation system. This section presents some of theguidance that is contained in the modules in the area of ventilation systemsand radiation protection of control room personnel.

The inspections of control -room ventilation systems and radiation protectionprovisions for control room personnel are performed during the construction,preoperational, and operational stages of plant life and are performed bydifferent regional staff groups. During the construction stages, the installa-tion of HVAC systems is inspected by the dnsite resident construction inspec-tors under the guidance of the 5OXXX series modules. During preoperational andoperational phases, both the emergency preparedness and health physics staffsinspect HYAC and radiological protection systems under the 52XXX and 53XXXseries modules as well as under the guidance of special emergency preparednessappraisal instructions. Portions of the modules and Instructions, which pro-vide guidance to regional inspectors are provided in this appendix.

2 CONSTRUCTION PHASE INSPECTIONS

During the construction stage, there are at least three different types ofinspections of control room ventilation systems that are performed by regionalinspectors. The first inspection occurs when the systems are reviewed duringinstallation. The other two inspections occur after the systems are installedwhen they are inspected by the emergency preparedness staff and by the healthphysics staff to assure that they will meet their intended function and thatthe applicant has appropriate procedures and has trained its staff in the im-plementation of the procedures.

The construction phase inspection programs are described in Inspection andEnforcement (IE) Manual Chapter (MC) 2512, "Construction Phase InspectionProgram." In this program there are a number of inspection procedures ormodules that expose the Inspector to the control room environment or cause himto examine hardware and/or software that impacts control room habitability.Although the inspection program of MC 2512 does not have a specific procedurecovering control room habitability systems, it has a number of procedures thatbring the Inspector in direct contact witt the systems on which the controlroom environment depends. Such procedures are found in procedural groups 3700,"Design, Design Changes, Modifications"; 4100, "Training"; 4900, "Piping";


rP.

5000, "Mechanical Components and Systems"; 5100, "Electrical Components andSystems"; 5200, "Instrumentation Systems and Components"; 5500, "Welding"; 5600,"Calibration"; 6100, "Surveillance"; and 6400, "Fire Prevention/Protection."

Construction inspections of safety-related HVAC systems have only been per-formed over the last few years and only recently has an inspection procedurebeen developed for this area. On October 1, 1983, Inspection Procedure (IP)50100, "Safety-Related Heating, Ventilating, and Air Conditioning (HVAC)Systems," was issued. The procedure is applicable to the inspection program ofMC 2512 and focuses on inspection of the HVAC system, which is one of the prin-cipal systems involved with control room habitability. IP 50100 specificallyaddresses ductwork, isolation dampers, radiation, smoke, and toxic-chemicalmonitors, air-intake elevation, air-handling units, and exhaust vents. Inaddition to hardware installation, this procedure examines quality assurance(QA) related to the hardware. The procedure calls for the review of the con-tractor's QA manual, review of the QA implementing procedures, review of workprocedures, personnel interviews of installation practices, and the review ofrecords. The record review determines the effectiveness of the documentationsystems by comparing records against requirements for accuracy and completeness.The record review covers such items as fan motors, HVAC control panels, elec-trical operators for isolation valves or dampers, electrical cables, fan assem-blies, service water cooling coils, backdraft dampers, fan assemblies, and iso-lation dampers and valves. IP 50100 focuses on safety-related HVAC systemsserving various areas with emphasis placed on the control room. Table E.2-2presents the objectives of IP 50100.

2.1 Results of an Inspection Using IP 50100

The following section includes parts of a construction phase Inspection report(050-322/80-04) that gives results of an inspection of a control room air condi-tioning system using IP 50100. This section of the report is reprinted here todemonstrate the items that were reviewed.

It should be noted that before IE Inspection Procedure 50100 was developed,these inspections were not as consistent as they are expected to be once theprocedure is fully implemented. This following inspection example reflects aninspection that can be considered more extensive than what has typically beenperformed.

2.1.1 Control Room Air Conditioning (CRAC) System

2.1.1.1 Documents Reviewed

Shoreham FSAR Sections 6.4 and 9.4.1 and the section containing NRC requestsand responses.

Regulatory Guide 1.52, "Design, Testing and Maintenance Criteria for AtmosphereCleanup System Air Filtration and Adsorption Units of Light-Water-CooledNuclear Power Plants," June, 1973 (R.G. 1.52).

ORNL-NSIC-65, "Design, Construction, and Testing of High-Efficiency AirFiltration Systems for Nuclear Application," C. Burchsted and A. Fuller,January, 1970 (NSIC-65).


_ ..I _

Table E.2-1 Summary of Inspection Objectives, IE Module 50100

.

I

IIllvlv

l

Il

Il|

|||s

|

50100-01 INSPECTION OBJECTIVES

011 To determine whether quality assurance (QA) plans, instructions, andprocedures for inspection of safety-related HVAC systems have beenestablished in the facility QA Manual.

012 To determine whether the technical requirements detailed or referencedin the facility Safety Analysis Report (SAR) associated with safety-related HVAC systems have been adequately addressed in the construc-tion specifications, drawings, and work procedures.

013 To determine through direct observation and independent evaluation ofwork, whether the installation of safety-related HVAC systems are incompliance with NRC requirements, licensee commitments, and codes.

014 To review samples of safety-related HVAC system records to determinewhether the licensee is adequately preparing, reviewing, and main-taining a system of quality records; whether there is reasonableassurance that the records reflect work accomplished consistent withNRC requirements and SAR commitments; and whether the recordsindicate any potentially generic problems, management control in-adequacies, or other weaknesses that could have safety significance.

These objectives are achieved by (1) review of contractor QA manual,(2) review of QA implementing procdures, (3) review of work proscedures, (4) observation of work and work activities, (6) review ofrecords, and (6) other specific and general guidance.

ANSI N510-1975, "Testing of Nuclear Air Cleaning Systems."

"Specification for Ventilation Filter Trains," Shoreham NPS, SHI-lOS withAddendum Nos. 1, 2 and 3.

Preopfrotlonal Test Procedure, PT 412,001, "Control Room Air CondftioningSytem/Control Room Loek lost,

Station Procedure, SP.23.412.01, Rev. 0, "HVAC-Control Room."

Station Procedure, SP.24.412.01, Rev. 0. "Control Room HVAC Operability andFlow Rate Test."

Station Procedure, SP.24.412.02, Rev. 0, "HYAC Control Room Emergency Mode."

Proposed Technical Specifications for Shoreham NPS Sections 3.7.2 and 4.7.2,"Control Room Emergency Filtration System."

Pertinent system piping and instrumentation drawings and logic drawings.


. ...- - .. -

-� I -�

I

Farr Company Procedures: L-53577E, "Activated Carbon Filters In-Place LeakTest"; L-58875A, "Air Distribution Test, HEPA and Carbon Filters"; andL-534600, "HEPA Filter Banks In-Place Leak Test."

2.1.1.2 Scope

The inspector, in company with construction engineers, toured the as-builtsystem in the plant and observed all major system components, piping, ductwork,and selected instrumentation and controls. The inspector also performed addi-tional system tours to note the storage conditions of installed equipment andmade independent measurements to determine selected as-built dimensions. Basedon document review and the system tours the inspector compared the as-builtsystem and the approved system test and operating procedures to the variousregulatory requirements and license commitments.

The inspector also reviewed the system and instrumentation design and systemprocedural steps for items which could potentially cause operator misinterpre-tation. With the exception of the below items, the inspector had no furtherquestions at this time.

2.1.1.3 System Design

10 CFR 50.57(a)(1) states in part that an operating license may be issued uponfinding that construction of the facility.has been substantially completed inconformity with the construction permit and the application, as amended, andthe rules and regulations of the commission. Based on the above review of theCRAC system, the inspector noted several instances where the system, as in-stalled, was not in conformity with the FSAR, RG 1.52, and NSIC-65. The itemsidentified which did not agree with these documents were as follows: sealwelds on filter mounting frames, filter mounting frame bolt size, HEPA filterarrangement, filter housing door size, filter housing lights, filter spacing,building elevators for maintenance, straightening vanes in filter housinginlet, ductwork design, and tornado missile protection for the East air intake.The inspector also requested information regarding the environmental qualifica-tions, as specified in RG 1.52, for nearby safety-related cabling and forpainted welds within the filter housing, which was not available during theinspection. These items were unresolved and designated as Item No.322/80-04-03.

2.1.1.4 Vendor Procedures

Paragraph 9.4.1.4 of the Shoreham FSAR states that the carbon and HEPA filterswill be leak tested in accordance with ANSI N510. The inspector noted that thepreoperational test for the CRAC system referenced Farr Company procedures forthese tests. The inspector reviewed the Farr procedures and noted there wereseveral areas in each procedure that deviated from ANSI N510. The inspectoralso stated that In general a vendor procedure used for a preoperational testshould be reviewed for content by the Joint Test Group (JTG) and approved priorto performance.

This Item Is unresolved pending revision of the filter test procedures andestablishment of a requirement for review of vendor procedures by the JTG.(Item No. 322/80-04-04.)


2.1,1.5 PreoperAtionA lest Procedure

During the review of the CRAC system preoperational test procedure, PT.412.001,the inspector noted the following items:

(a) The procedure does not specify whether the test will be run with ACU-14 Aand B on or off. The operation of these units could affect the flow rateto the CRAC filter trains. Hence, the design flow rate apparently shouldbe verified both with these units running and secured;

(b) The procedure currently does not verify the design flow rate of 4000 cfmthrough the filter trains. This flow rate is an item to be tested every18 months in the proposed Technical Specificdtions;

(c) The acceptance criteria for control room pressure is not specific (approx-imately 0.25 inches of water);

(d) The procedure does not test the Fan 25 automatic start feature when therunning fan fails during accident operation; and

(e) The procedure does not demonstrate the capability to manually close afailed outside air intake valve as assumed in the dose calculations pre-sented in answer to NRC FSAR question 311.8.

These items are unresolved and are designated as Item No. 322/80-04-05.

2.1.1.6 System Operating Procedures

During the review of the CRAC system procedures to be used for operating thesystem and for routine testing of the system after the plant is in operationthe inspector noted the following items:

(a) Procedure SP24.412.01 for surveillance testing does not contain a specificprocedural step to return the system to normal after the test;

(b) Procedure SP24.412.02 for surveillance testing demonstrates that the CRACsystem can maintain the control room at a positive pressure with respectto the outside atmosphere. The acceptance criteria, however, leaves nomargin for deterioration over the 18 month surveillance interval; and.

(c) Procedure SP23.412.01 for system operation in paragraph 8.1.6.2 has apotentially confusing statement regarding indication and switch position.

The licensee's representative stated that all three procedures would be revisedto correct the above noted items. This item is designated as Itefu No.322/80-04-06.

2.1.1.7 Instrumentation

During the review of the CRAC system and system procedures, the inspector alsoobserved available local and control room instrumentation. Based on thisreview the inspector noted the following:


�1

The control room indicators for flow transmitter FT-002 read 0-12 CFM or0-1200 CFM. Additionally, the meter does not contain a multiplier;

The outside air intakes are not labeled East and West or some equivalentlabeling to aid the operator in determining which side to manuallyisolate, as is required in the design-basis accident for :he system; and

The CRAC system does not contain an instrument which would provide per-manent readout of the filter train flow rate, as recommended in para-graph 4.h of RG 1.52. This flow rate is needed for periodic technicalspecification testing and for verification of proper system operationduring an accident situation.

3 PREOPERATIONAL INSPECTIONS

The operability of licensee ventilation system are inspected just prior tooperation to assure that they are installed in accordance with FSAR commitmentsand standard industrial practices. In addition the inspectors carefully reviewoperation procedures and staff training in procedure implementation.

The program of MC 2513 is simila; to the MC 2512 program by the fact that itdoes not have inspection procedures specifically covering control rpom habit-ability. However, the program does contain many procedures that would requirethe inspector to be present in the control room or would require the inspectorto examine related systems, components, or procedures that impact control roomhabitability. These procedures include procedural groups

35744 QA Program - Design Changes and Modifications35745 QA Program35749 QA Program - Tests and Experiments35750 QA Program - Test and Measurement Equipment41301 Inspection of Operating Staff Training42400 Plant Procedures Inspection42452 Emergency Procedures Inspection42451 Maintenance Procedures Inspection64703 Fire Prevention/Protection70304 Engineered Safety Features Test70305 Reactor Protection System Test70306 Loss of Offsite Power Test70308 Integrated Hot Functional Test70334 Engineered Safety Features Activation System Test70336 Residual-Decay Heat Removal System Test70339 Component Cooling Water System Test70340 DC Power System Test70341 Emergency-Standby Power Supply System Test82101 Emergency Preparedness83315 Radiation Protection

Some of the procedures presented above focus their inspection on licenseemanagement control programs that impact all plant systems and components.


I

There are a number of general procedures in the Inspection program of MC 2513that could impact control room habitability. Some of these procedures are

90711 Nonroutine Event Review92701 Followup on Inspector Identified Problems92702 Followup on Items of Noncompliance92703 Bulletin Followup/Action Letter Followup92704 Inspection of Responses to Headquarters Requests92705 Inspection of Responses to Regional Requests92706 Independent Inspection Effortn3701 Followup on Significant Event (that occurs while inspector is on site)

as well as a number of other procedures.

3.1 IE Preoperational Inspection Procedures

IE Inspection Procedure 83524 is used during the preoperational inspectionstages by the regional health physics staff and focuses on external occupa-tional exposure control. In these inspections, reviews of installations aremade against FSAR commitments and general industrial practices as well as pro-cedures used to maintain adequate external occupational exposure control. Pro-cedure 83525 contains the preoperational procedures that deal with Internaloccupational exposure control and it provides guidance on the inspection ofrespiratory protection equipment as well as ventilation systems. It is throughthe use of this procedure that control room ventilation systems and breathingapparatus are inspected prior to operation. Tables E.3-1 and E.3-2 provide asummary of the information contained in these procedures.

3.2 Results of Inspection (Preoperational)

Below is reproduced part of an inspection report (050-322/82-20) that addressespreoperational review of ventilation system testing dealing with the controlroom. The report indicates that certain control room testing will be reviewedat a later date and leaves this as an open item.

3.2.1 Ventilation System Testing

3.2.1.1 Inspection Report 50-322/82-20-03

3.2.1.1.1 Documents Reviewed

CG.000.004-5, "Instrument and Control Component Checkout and Calibration,"dated January 23, 1981

CG.000.037, "In-Place Testing of HEPA Filters and Charcoal Adsorber Stage,"dated July 30, 1982

ANSI-NS1O, 1975, "Testing of Nuclear Air-Cleaning Systems"

Regulatory Guide 1.08, Revision 0, "Preoperational and Initial Startup TestProgr4ms for Water-Cooled Power Reactors"

Shoreham Start-Up Manual


- __ Am

Table E.3-1 Inspection Objectives, Requirements, and Guidance, ofIE Module 83524 (External Occupational ExposureControl - Preop.)


01.02 To determine the adequacy of the licensee's personal dosimetry andcapability to effectively control the external exposure of onsiteworkers during emergency operations.

83524-02 INSPECTION REQUIREMENTS

02.01 Physical Controls

Determine whether radiation protection facility design features andshielding meet requirements and FSAR commitments.

02.02 Administrative Controls

b. Determine whether administrative measures to implement externalexposure controls during emergency operations are adequate, andwhether they satisfy licensee commitments.

83524-03 INSPECTION GUIDANCE

03.01 Physical Controls

Determine by direct observation and discussions with cognizant in-dividuals whether selected design features are as described in theFSAR and whether provisions for use of temporary shielding areadequate for normal and emergency operations.

3.2.1.1.2 Results of Inspection

The review of procedures and discussions with licensee personnel indicated thatan instrument and control component checkout was ongoing and that preoperationaltest procedures for the Control Room Ventilation system were in revision and/orbeing written.

The licensee had performed a preliminary housing leak test, but had not yetperformed testing of HEPA filters and charcoal absorbers.

Because the licensee has not yet established and/or revised procedures toaddress all preoperational tests of the control room ventilation system (CRVS),the inspector indicated that CRYS testing will be reviewed during a subsequentinspection prior to fuel load.

This open item was subsequently closed out in Inspection Report No. 050-322/83-03.Beloweis the followup inspectors' finding.


U

Table E.3-2 Inspection Objectives, Requirements, and Guidance ofIE Module 83525 (Internal Exposure Control andAssessment - Preop)


01.02 To determine whether the applicant can effectively control the inter-nal exposure of onsite emergency workers during accident conditions.

83525-02 INSPECTION REQUIREMENTS


b. Determine whether administrative measures to control internalexposures during emergency operations are adequate and whetherthey satisfy licensee commitments.

02.02 Engineering Controls

Determine whether engineering controls for limiting intake of air-borne radioactive materials meet requirements and FSAR commitments.

02.03 Respiratory Protection Equipment

a. Determine whether the program for use of respiratory protectionequipment meets requirements and FSAR commitments.

b. Determine whether the respiratory protection program foremergency operations is adequate.

83525-03 INSPECTION GUIDANCE


a. Aspects of administrative controls that may be examined include:

3. Adequacy of written procedures for controlling internalexposure.

03.02 Engineering Controls

Aspects of engineering controls that may be examined include:

a. Ventilation systems with air flows from areas of low potentialairborne radioactivity to areas of higher potential airborneradioactivity.

b. Provisions for use of auxiliary ventilation systems to providelocal control of airborne contamination.


�M

Table E.3-2 (Continued)

03.03 Respiratory Protection Equipment

b. Review procedures and selected records, hold discussions withcognizant individuals, and observe samples of equipment; forexample, equipment in emergency kits, in the Control Room, inthe Operational Support Center, or in the Technical SupportCenter. In addition to the applicable factors specified in03.03a, above, consider the following:

03.04 Air Sampling for Assessing Individual Exposure

Aspects of the air sampling program that may be considered include:

a. Capability for representative sampling of air in a zone occupiedby workers. (See ANSI N13.1-1969 (R 1982), Section 4.2.1.1 andSection 6.]

3.2.1.2 Report No. 050-322/83-03

Closed Inspector Followup Item (50-322/82'20-03). Complete review of ControlRoom Ventilation System Test procedure. Revision 2 has been written andapproved for procedure PT 412.001-2, Control Room Air Conditioning System, Con-trol Room Leak Test. Preliminary filter testing has been conducted with final-ized procedure CF 000.037 with TGN-1. The inspector examined all documentspertaining to this item. This item is closed.

3.3 Emergency Preparedness Appraisals

All licensees' emergency capabilities have been systematically appraised underthe emergency preparedness appraisal program conducted by the regional officeswith support from NRC headquarter and contractor laboratories. During theseappraisals, inspectors reviewed all the systems associated with the licensees'emergency response capabilities. In reviewing control room NVAC systems inspec-tors generally concentrated on procedures and operation of these systems, ratherthan on their design or installation. The Initial round of emergency prepared-ness appraisals was performed during 1981-1982. These inspections are stillongoing. Some are conducted during the preoperational phase. Others are con-ducted during startup.

The inspection reports of these appraisals generally highlight problem areas,so, in many reports, control room HVAC systems are not discussed although theywere reviewed during the appraisal and no problems were found. Below are re-produced some.of the inspection findings from five emergency preparednessappraisals that relate in some extent to the control room habitability area.The majority of the concerns and open items that appear below have beenaddressed by the licensee since then and reviewed during subsequent inspections.

*


3.3.1 Report Nos. 5O-317/81-19; 50-318/81-18

The control room was designed to remain habitable under the accident conditionsdescribed in the FSAR. The auditors determined however that the control roomdid not contain radiation monitoring equipment to indicate the presence ofeither direct radiation or airborne contamination. The system used to activatethe recirculation mode of the control room ventilation system consisted of asmall diameter (approximately 3/8 in. I.D.) line attached to the ventilationintake duct and run to a remote shielded detector. The auditors were unable toverify that the line incorporated an isokinetic probe in the duct to assurethat a representative sample was being taken. Further, the location of theremote detector was in close proximity to the sampling system and ducts of theauxiliary building main stack, thus making its readings questionable underaccident conditions.

3.3.2 Report No. 50-244/81-22

The auditors toured the R. E. Ginna control room. This tour included an auditof emergency kits, documentation (e.g., emergency plan and procedures, plantdrawings), readouts of area and process monitors, communications equipment, andmeteorological instrumentation. The content of the emergency kit was as speci-fied in SC-1.15, "Inspection of Emergency Equipment." The licensee'maintaineda complete set of relevant plant drawings and procedures in the control room.The auditor examined 65 procedures related to emergency preparedness to verifycurrent revisions were in place;. Included in this audit were the EmergencyPlan (SC-1) as well as procedures in each of the following categories: alarmresponse, emergency system operation, health physics, and site contingency.The auditors found one outdated procedure. (See Section 5.5.3 of this report.)Readouts for instrumentation to be used in accident assessment and emergencyclassification appeared to be adequate and reasonably accessible for timelyinterpretation. There was no readout in the control room for the seismicaccelerograph, but the auditors concluded that existing procedures wouldallow determination of seismic activity. Equipment for sampling and monitoringthe radioactive airborne concentrations in the control room was not being main-tained in the control room.

Based on the above findings, this portion of the licensee's program appears tobe acceptable, but the following matter should be considered for improvement:

Pre-position sampling and monitoring equipment to det'r.t and measure air-borne and particulate radioactivity in the control room. (50-244/81-22-08)

3.3.3 Report No. 50-213/81-14

The auditors toured the control room and examined the monitoring Instrumenta-tion and documents applicable to emergency response. Updated copies of theEmergency Plan and Emergency Plan Procedures as well as Emergency OperationsProcedures were available in the control room. Radiation shielding and a ven-tilation system with particulate (HEPA) and charcoal filters in place ensuredthe habitability of the controliroom under accident conditions. Portable radi-ation.detection instruments, respiratory equipment, portable lighting, and com-munication equipment were maintained in the control room.


��M in

3.3.4 Report No. 50-387/82-12

Unit 1 and Unit 2 share a common control room and thus communications betweenthe two units is available without the use of special equipment although atemporary wall exists now while Unit 2 is under construction. Direct communi-cations to the TSC (Technical Support Center), EOF (Emergency OperationsFacility), and local offsite agencies was available, as was an extension of theNRC-ENS phone network. The two units relied on common instrumentation formonitoring meteorological, hydrological, and seismic conditions and for certainarea radiation monitor (ARM) locations. The control room ventilation wasequipped with HEPA and charcoal filters and the air intake was monitored forhazardous substances. The control room ventilation system automatically iso-lated and switched to recirculation upon receipt of signals from the intakeradiation or chlorine monitors. Upon receipt of alarms from the air intakesmoke detectors, the system would be isolated manually by the control roomoperators. Representatives of the plant Indicated that, once the constructionof the control room (Unit 2) was completed, a continuous air monitor (CAM) wouldbe installed in the control room to monitor the atmosphere for particulates,radiolodines, and noble gases. There was an ARM in the control room with arange of 0.01 to 100 mR/hr.

3.3.5 Report Nos. 50-277/81-28; 50-278/81-31

The auditors examined the control room as an emergency facility and found thefollowing:

Emergency plans and implementing procedures are available in the multi-unitcontrol room for Units 2 and 3.

Emergency action levels were understood and instruments were marked with thetrip levels which would be used by the operators to initiate emergency actionsand provide an indication of the event classification.

The control room was supplied with respiratory protection and self-containedbreathing apparatus.

The necessary equipment to assist in dose assessment such as the map of theEPZ and overlays used to establish the dse profile in the plume pathway werepresent.

Meteorological information was available to the operations personnel.

Since Units 2 and 3 shared a common multi-unit control room, communicationbetween units are automatic and readout of instruments between units arereadily available.

Portable radiation monitoring equipment was assigned to the control room.

A continuous air monitor for the room air was in place and operable.

Monitors were In plat# and operable for the intake air to the control room,

All required communication lines were installed.

Control Room Habitability Report E 12

�M

4 OPERATIONAL PHASE INSPECTION

The lightwater reactor inspection programs that apply after an operatinglicense is issued are described in IE MC 2514 and IE MC 2515, startup testingand operations inspection programs, respectively.

The program of MC 2514 focuses on inspector's review of procedures, witnessingof activities, and review of data on startup test conducted by the licensee.Many of these tests require observation of the control room or require theinspector to examine related systems, components, or procedures that impactcontrol room habitability.

Within the program of MC 2515, inspection procedures generally do not addressspecific plant systems or components. The program procedures of MC 2515 coverlicensee programmatic areas along the lines of those outlined in the NRC Sys-tematic Assessment of Licensee Performance (SALP) program. These areas includeoperations, maintenance, refueling, fire protection, emergency preparedness,surveillance, radiological controls, security and safeguards, and qualityassurance. The procedures, at best, could result in direct or indirect inspec-tor contact with systems or components affecting control room habitability.Examples of these inspectian procedures are 37700, "Design Changes and Modifi-cations"; 61716, "Monthly Surveillance Observation"; 62703, "Monthly MaintenanceObservation"; 64704, "FUre Protection/Prevention Program Implementation";71707, "Operational Safety Verification"; 71710, "ESF System Walkdown." Inaddition, the program of MC 2515 contains several procedures that requireinspector followup for circumstances such as those resulting from licenseeevent reports (LERs) (IP 92700), noncompliance (IP 92703), and plant events(IP 93702). These inspection procedures could lead the inspector to reviewsystems or components that have an impact on control room habitability.

Inspection Procedures 83724 and 83725 are similar to Procedures 83524 and 83525of the preoperational stage, respectively, except that they apply to operationalinspections. The operational procedures emphasize, in addition to those de-scribed in Section 3 of this Appendix, changes in procedures, changes insystems, and audits and de-emphasize review against FSAR commitments or reviewagainst design criteria.

Routine, annual inspections are performed by the regional staff at each powerreactor in the emergency preparedness area. Inspectors do not normally reviewthe control room HVAC systems or associated procedures during these inspectionsunless changes in the systems have been made since the last inspection.

In the emergency preparedness area IE Inspection Procedure 82211 is used by theregional staff in performing operational inspections. The objective of Proce-dure 82211 is to determine that provisions for equipment, facilities, and pro-cedures exist for protecting onsite emergency workers. The inspection require-ments include reviewing emergency procedures to determine that appropriateradiation protection during emergencies will be established. It is one of manyemergency preparedness modules and focuses on equipment and facilities for pro-tecting onsite emergency workers.


1111111, �1

During an inspection it is not possible for every piece of equipment or eachpart of the facility to be inspected within the budgeted time. Consequentlythe inspector will select parts of the program to be inspected on a randombasis with emphasis on past problem areas.

In addition to inspection modules, other documents are used in performinginspections. One document used by the emergency preparedness inspection staffentitled "Emergency Preparedness Appraisal Program" (Temporary Instruction2515/55, Reference 1) provides guidance for the initial inspections that wereconducted at each facility and for inspections that will be conducted at NTOLs.Table E.4-1 provides the guidance presented in this document which pertains tocontrol room habitability.


Table E.4-1 Guidance Contained in Emergency Preparedness ProgramTemporary Instruction 2515/55, Reference 1

EMERGENCY FACILITIES AND EQUIPMENT

I. Objective

To verify that the licensee has emergency facilities and equipment that willallow him to efficiently respond to the scope of emergencies defined in thisplan and procedures.

II. Basis

The nature of emergency facilities and equipment varies considerably from onelicensee to another. It is often dependent on the design and physical char-acteristics of the licensee's buildings, site, and the number of units operating.

Emergency equipment such as types of instrumentation, sampling media, samplers,etc., are subject to licensee's preferences. Emergency equipment not only hasto be readily available and consistent with the plan and procedures, but itscharacteristics must be such that users can accomplish their intend~ed actionsand objectives with the use of the equipment. For example, if the statedobjective is to be able to detect airborne radioiodine concentrations of atleast 1E-07 pCi/cc, the instrument filter media, and air samplers and theirintrinsic parameters (e.g., instrument sensitivity, retention efficiency ofsampling medium, air sampler's flow-rate, etc.) must be such that detection andmeasurement can, in fact, be readily and accurately determined. A substantialchange in any of the critical parameters (e.g., decrease in detector efficiency,lower medium retention efficiency, change in the flow-rate, etc.) will signi-ficantly alter the results, and the objectives of the emergency plan and proce-dures may not be achievable in this area.

The above considerations require that all equipment and facilities should bereviewed with great care for technical details, to insure that, in addition tobeing available, the results, demanded by the licensee's emergency plan andprocedures, are capable of being produced.

The scope of an inquiry into technical detail may be limited to emergencyequipment other than that used on a routine basis (e.g., by the health physicsgroup) or to equipment that, although used routinely, is modified in any wayfor custom use during emergencies (e.g., calibrated differently, etc.).

Licensee checks of operability should contain provisions for checks withsources, instructions on how to perform such tests, and criteria for acceptanceor rejection of equipment.

Adequacy of airborne radiofodine and particulate detection and measurementsystems should consider:

(a) efficiency of the detector system;

(b) adsorption characteristics of the sampling medium;


Table E.4-1 (Continued)

II. BASIS (Continued)

(c) retention efficiency of the sampling medium;

Md) air flow rates and sampling time;

(e) determination of amount of radioactivity in sampling medium;

(f) calculations and data;

(g) shielding of detectors to prevent interference from other radiationsources;

(h) equipment input (AC, DC) consistent with use.

Throughout the review, the inspectors consider the impact of multi-unit opera-tion on the emergency facility add equipment adequacy. Certain multi-unitsites may use common monitors with the readouts in only one of the two controlrooms.

III. Guidance

A sampling of records is selected to verify that inventories, maintenance andcalibrations are being performed. Types of equipment selection include: surveyinstruments; emergency kits; communications; area and process radiation monitors,respiratory protection equipment, air samplers; dosimeters, etc.

Each generic type of emergency kit is inspected and the accuracy of theinventory, location, operability and serviceability of contents is verified.Operability checks of radiation survey equipment are performed using thelicensee's emergency equipment inventory procedure.

The Technical Support Center (TSC), the Operations Support Center (OSC), andthe Emergency Operations Center (EOF), the control room and associateddecisional aids (e.g., isopleths, procedures, conversion charts, etc.? areinspected.

Control Room Habitability Report E-I&