ML20151K550
| ML20151K550 | |
| Person / Time | |
|---|---|
| Issue date: | 11/30/1984 |
| From: | Parr O Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20151H089 | List:
|
| References | |
| FOIA-88-92 GL-81-12, NUDOCS 8412100346 | |
| Download: ML20151K550 (25) | |
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UNITED STATES
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NOTE TO: ASB Members FROM:
Olan D. Parr, Chief Auxiliary Systems Branch, Division of Systems Integration
SUBJECT:
FIRE PROTECTION REVIEW GUIDANCE 1.0 Introduction Paragraph 50.48(b) of 10 CFR became effective on February 17, 1984 and required all plants licensed before January 1, 1979 to meet the require-ments of Section III.G, III.J, and III.0 of Appendix R.
Additionally, paragraph 50.48(c)(5) requires that any modifications needed to meet Section !!!.G.3 must be reviewed and approved by the NRC. Since issuance of these requirements there have been several pieces of guidance written, such as Generic Letter 81-12 and internal ASB memoranda, to as.tist in the review of safe shutdown succiittals. However, none of these pieces of guidance have been coalesced into a single document. The puroose of this report is to present one paper which can be used in tne evaluation of safe shutdown submittals. An important point to remember while perfoming Appencix R reviews is the definitions of "important to safety", "safety
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related" and "safe shutdown" as defined in the introduction to Appendix R.
These definitions are to be applied to all Appendix R reviews.
2.0 Section III.G of Acoerdix R.
2. '. Ge.eral RecuirementsSection III.G of Appendix R provides for four methods for crotecting equipment needed for hot shutoown from a fire. Three of these methods are to provide the mear.s for protecting redundar.t systems, including cables, equipment and associated circuits, and are: (1) separation by a three-hour fire barrier, (2) separation by a horizontal distance of more
- han 20 feet having no intervening combustibles and a fire detection ind autenatic suporession system, or (3) separation by a one-hour fd.re barr4er with a detection or autornatic suppression system. The fourth method provices for alternate shutdown cacability wnich is independent of ecuipment, cables, and associated circuits of redundant system:
be camaged by fire.
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Attachmert I contains a discussion on safe shutdown capability along with a description of as:ociated circuits and infomatior, which the utility should provide, or be requested to provide, in order to assess the acceptability of the associated circuit design. Attachment 2 is the information needed to review the systems, edutoment, and procecures of the alternate snutdown cacao 111ty. Attachment 3 contains a copy of Generic Latter 81-12 which was sent to all utilities with plants licensed before January 1, 1979 anc contains guicance on fire protection. In i
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4' 3 - Revision 1 acceptability of the design. Since issuance of that guidance, there have been several expansions on associated circuits.
In particular, the potential for multi-high impedence faults in AC power circuits could result in the loss of power to safe shutdown equipment.
Figure 1 contains a sketch of circuit designs which could result in the loss of needed power to safe shutdenn equipment. As can be seen in Figure 1, redundant divisions of safe shutdown cables are properly separated in accordance with Appendix R criteria. However, a fire in fire area A would result in loss of Division A safe shutdown equip-ment and cause damage to nonsafe shutdown cables associated with the Division B bus. Further, the individual fault current resulting from i
the fire damage in the nonsafe shutdown cables may not be enough to trip the indivfdual breakers (B and B ), but the sum of the faults may be sufficient to trip the main brea,ker, B. If this were to 3
occur,theDivisionBbusandthecorrespondi$gredundantDivisicnB i
safe shutdown equipment would be lost.
Tha ASB reviewer should, therefore, request an analysis by each applicant which confims that the above situation does not occur for 1
postulated fire (high inpedence faults) in all AC power cables in each i
fire area containing one or more safe shutdown divisions. Some newer plants may be able to show that no division A and B cables are located i
in a single fire area. This would be acceptable. If the analysis indicates that this condition could occur, then either some number of cables should be protected from fire damage (additional cable wraps or relocation from the fire area of concern) in order to reduce the total 1
fault current below the setting for breaker B}s,hing power to a faulted or, the applicant may provide an appNpriate procedure for reestabl bus powering safe shutdown loads (i.e., identifying the failure to the operator so that he can strip the faults from the bus, and close breaker B to reestablish shutdown train B).
3 Another area of concern is the spurious operation of equipment for the i
case of three-phase AC and non-grounded two-wire DC power circuits. For l
the three-phase AC circuit, the possibility of getting a hot short on all three circuits in the proper phase to cause spurious operation of a motor is considered an impropable event. Therefore, utilities can be granted relief from analyzing this case. For non-grounded DC circuits.
cable-to-cable faults and wire-to-wire faults are postulated to occur.
Hence, these types of faults must be considered during the reviem However, if the utility can demonstrate that non-grounded cable-to-cable DC shorts are impropable, relief can be granted. Hot shorts in three-phase AC and non-grounded DC circuits must be analyzed and corrected for spurious operation of Hi/Lo pressure interfaces.
During the Fitzpatrick review, the staff did not require that the licensee pursue the three-phase and DC circuit issue discussed above.
However, for the DC circuits, the licensee was required to request an exemption from Section III.G.2 of Appendix R.
The review of the exemption is performed by PSB.
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n-4 - Revision 1 2.2.3 Transfer Switch Isolation Circuitry During a fire protection inspection at the Wolf Creek Generating Station, it was discovered that for a fire in the control room.
t-isolation transfer switches for certain hot shutdown systems /com-ponents had to be switched to the alternate or isolated position prior to damage occurring to these circuits. If this were not accom plished in time, uses would have to be replaced in order to make the system / component operable. This situation existed because the transfer switches did not place new/radundant fuses into the control power circuit, but left the existiy (assumed blown) set of fuses in the circuit. For most of the transfer switches the situation did not cause a problem since the desired effect after isolation was the deenergization of power. In other instances where the system /cmponent had to be operable or where operation might be required to override a spurious actuation (such as a motor operated valve) replacement of fuses would be required if blown.
At the Wolf Creek facility, the transfer switches at the remote shut-down panel had redundant fusing so that only transfer switches at other local stations (which were designed / installed after those on the remote shutdown panel) that mainly involved support systems operability or correction of spurious operations were identified as a concern. Wolf Creek either modified the existing switches or installed new switches for certain components such that redundant fusing does exist with a new (different) set of fuser switched into
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the circuit, when the switch is nlaced in the isolated mode. Alternate shutdown procedures were also modified such that shutdown could be achieved assuming imediate evacuation of the control room and possible control room circuit damage with possible spurious operation of equipment prior to isolatien outside the control room.
This situation may exist at other facilities and may involve other areas of ti.e plant that require alternate shutdown capability and could include the switches on the alternate / remote shutdown panel. The reviewer shot.ld ensure that the utility has reviewed its safe shutdown circuitry and has taken any applicable cortective action necessary to ensure that the isolation transfer switches required for post-fire safe shutdown capability do not rely on the continuity of fuses that may be blown due to control room (or other area) circuit fire damage. The following are possible courses of action to be taken by the utility.
1.
Review the electrical design drawings for the existing isolation transfer switches to detemine where and if this situation exists.
2.
Provide modifications to existing switches and/or install new isclation witches where necessary to provide redundant fusing such that a blown fuse will not require replacement to achieve and niaintain hot shutdown, and 3.
In the interim, ensure that sufficient replacement fuses are available in the event a fire were to blow fuses and thereby disable a required function / operation for alternate shutdown.
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4A 2.2.4 Current Transformers In Ocfober 1982, BHL identified a problem with open-circuit operation of current transformers (CT) which could exacerbate the consequences of a control room fire. The concern stems from the fact that a control room fjre could result in a breakdown of the power feeder insulation and cause a second fire. Attachment 7 contains the detailed descrip-tion of the probium along with the applicant response to a PSB question on the subject. The Power Systems Branch has reviewed this concern and concluded that the BNL concerns were overly conservative and recommended no further action on this issue. Therefore, the ASB reviewer should be aware of this concern; however, no other action is required. Attach-ment 9 is the PSB evaluation.
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E NOV 3 0 1984 3.0 Need For Source Range Flux, Reactor Coolant Temperature, And Steam Generator Pressure Incication Section III.L.1 of Appendix R requires that alternate shutdown capability be able to achieve and maintain suberttical reactivity conditions.
Section !!!.L.2 requires direct readings of variables necessary to perform and control shutdown, included in the variables to be conitored are source range flux, reactor coolant. temperature, and sttam generktor pressure.
Monitoring of source range flux is the quickest means of assessing reactor criticality. The reactor coolant temperatures, in conjunction with pressure, are necessary for cooldown and control of natural circulation, subcooling margin, and pressurized thermal shock. Improper pressure control in the steam generators could result in an imbalance in heat removal leading to excess depressurization ar.d a bubble ir, the reactor coolant system high point. Attachment 8 contains the staff position on the need to monitor these parametert.
4.0 Automatic Depressurization Systems For BWRs Some boiling water reactor safe shutdown submittals have proposed the use of the automatic depressurization system in conjunction with the low pressure coolant injection system as an alternate shutdown method.
Although the use of these systems would result in a short-tenn uncovery
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of the upper portion of the core, referenced analyses have indicated that the uncovery time is sufficiently short and the amount of uncovered fuel small encugh that cladding integrity would not be threatened.
Therefore, the use of the ADS and LPCI is acceptable but is considered an exemption to Section III.L of Appendix R because III.L does not per: sit core uncovery.
S.C Solid Pressurizer Operation During the fire protection meetings held in the region with all applicants and licensees, the subject of whether pressurizer heaters were required for hot shutdown under Appendix R arose.
The question and staff response are given below and represent the position on solid pressurizer opcration.
Question Most PWRs do not require pressurizer heaters to maintain stable i
conditions. In fact, the Comission does not consider heaters to be important to safety and they are not required to meet Class 1E requirements. Are they required for hot shutdown under Appendix R? If yes, then how does a plant meet the separation recuirements of Section !!I.G.2.d. e, or f without major structural alternations to the pressurizer?
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Response
One train of systems necessary to achieve and maintain hot shutdown con-ditions must be free of fire damage. PWR licensees have demonstrsted the capanility to achieve and maintain stable hot shutdown conditions without the use of pressurizer heaters by utilizing the charging pump and a water solid pressurizer for reactor coolant pressure control.
6.0
SUMMARY
OF ATTACHMENTS 1.
Discussion of Safe Shutdown Capability 2.
Information for Reviewing Alternate Shutdown 3.
OL Questions on Safe Shutdown 5.
Regional Fire Protection Workshop Questions and Responses 6.
Discussion of Allowable Repairs 7.
Description of Circuit Transformer Problem 8.
Staff Position on Source Range Flux, Reactor Coolant Temperature, and Steam Generator Pressure Monitoring k
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Division of Systems Integration cc:
R. Berr.ero L. Rubenstein I
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FIGURE FIRE AREA 2 FRE AREA I FIRE NON SAFE SHUTDOWN,
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SAFE SHUTDOWN CApAB11.1TY The following discusses the requirements for protecting redundant and/or 4lternative equipment needed for. safe shutdots in tha event of a fire.
The requirements of Appendix A address hot shutdown equipment which must be
. free of fire' damage. The followtng.rpquirements also apply. a cold s,butdown equipment tf tha itcensee elects to dam'onstrate that the. equi;nent..is to.be free o,f. fire. damage. AppandG R does allow.re'p'airable damage ?.o cold shutdown ecutoraent.
Us'ing the requirements of Sections III.6 and III.t of Appendix R, the ape-",.
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" bilityrto achieve het shutdown must exist given a fire 'i any area of the plant in con. function with a loss of offsite power for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Section III.G of Appendix R provides four methods for ensuring that the hot shutdown capa-bility is protected from fires..The first three options as defined in Section III.G.2 provides methods for protection frors fians of equipment ne'eded for
. hot shutdown:
1.
Redundant systems including caSles, equipment, and associated circuits may be separated by a three-hour fire rated barrier; or, 2.
Redundant ryttens.tncluding ca51es, equi;aent and associated circuits may
.be separated by a horizontal distance of more than 20 feet with no inter-vening coveustibles. *In addition, fire detection and an automatic fire
. suppression system are required; or.
- 3. 4edundant s 'tmas in61udirg cables, equipment and associated circuits say ge enclosed ay a ene-hour fiee rated barrier. In addition, fire 4etectors i
W an anteestic fire esppress Wa. system are required.
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2 The last. option as defined by Section III.G. provides an alternetive shutdown capability.to the redundant trains damaged by a fire.
- 4. ;Allernative shutdown equipeent must be independent of te cables, equip.
.aent and associated circuits of'the redundant systems damaged by the fire.
Asseciated Circuits of Conc 1rn The following discussion provides A) a definition of associated circuits,for i
Appendix R consideration. B) the guidelines for protecting the safe'shutdcwn l ').
capability from the fire-induc.ed failures of associated circuits and C) the in-for=ation required by the staff to review associated circuits. The definitien of essociated circuits has not changed from the February 2D,1981 generic letter; but is merely clarified. It is important to note that our interest is only with those circuit (cable's)'whose fire-inder.ed failure could affect shutdown.
The guidelines for protecting the safe shutdown capability from the fire-induced r
i failures of associated ctreuits are not recuiree.ents. These guidelines should i
be used only as guidance when needed. 'fhese guidelines do not limit the alter-
. natives uailable to the licensee for protecting the shutdown capability.
All proposed methods for mtection of the shutdown capability from fire-induced 1i!
failures will be evaluated by the staff for acceptability.
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Our concern is th : circuits within the fi*e area,wjl1 receiv,e, fir,s damage A.
which can affect shutdown capability and thereuy prevent post-fire safe I
- hutdown. Associated Circuits
- of Concern aridefined as those cables (safety raated, non-safety related, Class 11, and non-Class 1E) that:
- The definiti n for assuiated circ its is not exactly the same u
as the definition pretented in IEEE-3841977.
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Have a physical separation lmss than that required by Section I21.8.2 of Appendix R.and; a
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Have one of the following:
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a cormnon power source with the shutdown equipment (redundant or alternative) and the power source is not electrically protected from the circuit of concerp by c'cordinated breakers, fuses, or similar devices (see diagram 2a), 'or
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a connection to circuits,of equipment whose spuricus operatien would adversely affect the shutdown capability (e.g., RXR/RCS isolation valves, ADS valves, PORYS, steam generator atmospheric du:np valves, instru entation, steam bypass, etc.) (see diagram 2b), or a corcen enclosure (e.g., raceway, panel, juaction). with the shutdown c.
f cables (redundant and alternative) and, I.
(1) are not electrically protected by circuit breakers, fuses or simi-1ar devices, or (2)will allow propagation of the fire into the c:mnon j
enclosure, (see diagram 2c).
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EXAMPLES OF ASSOCIAT
'RCtll1S OF CONCERN,
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The following guidelines are for protecting the shutdown capability from fire-induced failures of circuits (cables) in the fire area.
The guidance provided.below for interrupting devices applies only to new devices installed to provide electrical isolation of associated circuits of concern, or as part of the alternative or dedicated shutdown system.
Previous coordina-tion analyses need not be reanalytt.d; however, breakers that were not included in previous reviews, will require a encrdination analysis.
The shutdown capability may be protected from.the adverse effect of damage to
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associated circuits of cor.r.am by the following methods:
1.
Provide protection between the associated circuits of concern and the shutdown circuits as per Section 122.G.2 of Appendiz R, or 2.
a.
For a coernon power source case of associated Eircuit:
Provide lead fuse / breaker (interrupting devices} to feeder fuse / breaker coordination to prevent loss of the redundant er alternative shutdown power source. To ensure that the foll'owing t
coordination. criteria are met the 'forlowing should apply:
1 (1) The associated circuit of concern interrupting devices '
(breakers or fuses) ticie-overcurrent trip characteristic for all circuits faults should cause the interruptins device to interrupt the fault current prior to initiation of a trip of any upstream interrupting device which will cause a loss of the ecmon power. source, (2) The power source shall supply the necessary fault current for sufficient time to ensure the proper without loss of function of the shutdcdn loads.
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. ' The acceptability o'f a particular interrupting device is consider
, demonstrated if the following criteria are met:
a (1) The interrupting device design shall be factory tested to verify overcurrent protection as designed in accordante with t
the applicable UL, ANSI, or ND% standards.
(ii) For low and medium voltage switchgear (480 Y and above) circuit breaker /protactive relay periodic testing shall demonstrate,,that the overall coordination scheme remains within the limits specified in the design criteria. This testing may be performed as a series of overlapping tests.
(iii) Holded case circuit breakers shall pericdically be manually exercised and inspected to insure ease of.operatien. On a rotating refueling outage basis a sample of these breakers shall be tested to determine that breaker drift is witnin f
that allowed by the design criteria. 3reakers should be tested in accordance with an accepted QC testing methedology such as MIt. STD 10 5 D.
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{ (iv) Fuses when used as interrupting devices do not require r
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selected for proper coordinatien are not accidentally used.
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For circuits of equipmer)t and/or components whose spurious operatien would affect the capability to safely shutdown:
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-G-(1) provide a means to isolate the equipment and/or components from the fire area prior to the fire (i.e., remove power cables, open circuit breakers); or (2) provide electrical isolation that prevents spurious operation.
Potential isolation devices IMClude breakers, fuses, ampli-fiers, control switches, current XFRS, fiber optic couplers, relays and transducers; c'r (3) provide a means to ' detect spurious operations and then proce-dures to defeat the maloperation of equipment (i.e., closure of the block valve if PORY spuriously operates, opening of the breakers to remove spurious operation of safety injection);
.i c.. For corr::en enclosure cases of associated circuits:
u (1) provide apprcpriate measures to prevent propagation of the fire; and i
(2) provide electrical pr:tection (i.e., breakers, fuses or similar devices)
We recognize tr.at there are different apprcaches which may be used to C.
reach the same objective of determining the interaction of associated circuits with shutdown systems. One approach 1,s to start with the fire area, identify what is in the fire area, and determine the interaction between what is in the fire area and the shutdown syste s which are outside the fire area. We have entitled this approach, 'The Fire Area Approach." A second approach which we have named "The Systems Approach" would be to define the shutdewn systems around a fire area and then deter =ine e
those circuits that are located in the fire area that are associated with the shutdown system. We have p spared two sets of requests for information, one for each approach. The licensee may choose to respond
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I to either set of requests depending on the approach selected by the licensee FIRE AREA APPROACH 1.
Fer each fire area where an alternative or dedicated shetdown method, in accordance with section III.G.3 of Appendix R is provided, the j
following information is required to demonstrate that associated i
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circuits will not prevent operation or cause maloperation of the alternative or dedicated shutdown method:
Provide a table that lists all the power cables in the fire area a.
that connect to the sane power supply of the alternative or 1
dedicated shutdown method and the function.of each power cable listed (i.e., power for RHR pump),
b.
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Provide a table that lists all the cables in the fire area that i
were considered for'possible spurious operation which would adversely affect shutdown and the function of each cable listed.
I Provide a table that lists all the cables in the fire area that c.
I share a con =en enclosure with circuits of the alternative or dedicated.thutdown sy' stats and -the function of esch cable listed.
e d.
Show-that fire-induced failures (het sherts, open circuits or shorts to ground) of each of the cables Ifsted in 4f b, and c wil1 j
not prevent operation or cause malooeration of the alternative t
4 or. dedicated.shutdewn method.
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For each cable listed in a, b and c where new electrical isolation has been provided or sodification to' existing electrical isolation has been made, provide detailed electrical schematic drawings that a
show how each cable is isolated from the fire area.
SYSTEMS APPROACH 1.
For each area where an alterr.atfve or dedicated shutdown method, in accordance with Section III.G.3 of Appendix R is provided, the following infor: nation is required to demonstrate that asscciated
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circuits will not p'reiren' operation or cause maloperatien of the t
alternative or dedicated shutdown method:
a.
Describe the methodology used to assess the potential of associated
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capability. The description of the methodology should include the methods used to identify the circuits which share a ec=on power supply or a conron en:losure with the alternative or dedicated I
shutdown system and the circuits whose spurious operation vould affect shutdown. Additionally, the description should include the methods used to identify if these circuits are associated circuits of concern due to their location in the fire area.
b.
Provide a table that lists all ass:ciated circuits of concern 1scated in the fire area.
c.
Show that fire-induced failures (hot shorts, open circuits or shorts to ground) of each of the cables listed in b.will not prevent operation or cause maloperation of the alternatiie or.
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dedicated shutdown method.
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d.
For each cable listed in b.where new electrical isolation has been provided, provide detailed elecirical schematic drawings that
.show how each cable is iso 1ated from the fire area.
Provide ~a location at the site er other offices where all the e.
tables and drawings generated by this methodology approach for. the associated circuits review may be auditad to verify the information provided above.
Hir,9. tow MESSURE INTERFACE 1.-
For either approach chosen the fallowing concern dealing with high-low pressure u,terface should be addressed.
2.
The residual heat removal system is generally a low pressure syste=
that interfaces with the high pressure primary. coolant system.
To preclude a.LOCA through this interface, we require compliance with.
the recormendations of Branch Technical Pesition RSB 5-1.
Thus, the interface most likely consists of two redundant and independent matcr operated valves.
These two motor operated valves and their associdted cables may be subject to a single fire hazard. It is our concern that this single fire could cause the two valves to open resulting in a fire initiated LOCA through the high-low pressure system interface.
To assure that tnis interface and other high-low pressure interfaces are adequately, protected from the effects of a single fire, we require the following information:
a
. Identify each high-lew pressure interface that uses redundant a,
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electrically controlled devices (such as two series motor operated valves) to isolate or preclude rupture of any primary coolant t
boundary.
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For each set of redundant valves identified in a.. verify the b.
. redundant cabling (power and control) have adequate physical 1
separation as required by Section III.G.2 of Appendix R.
l For each case where adequata sap: ration is r. t prcvide,!. sh:*.: thet c.
fire induced failures (het short, open circuits or short to ground) of the cables will not cause maloperation and result in a !.0cA.
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2 Ul:LOSURE 1 REWRITE OF SECTION 8 REQUEST FOR ADDITIONAL INFDRMTION The following is a. rewrite of the. staff's. request fon. additional infometion
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4encerning design modification to a***. the requirments ef Section.III.G.& of Appendim P..
The following contains no new requests but ivanrely a rewording of Section 8 of. Enclosure 1 of the February 20, 1981 generic letter.
- 1. 7dentify those avers of the 71an>that will not meat the requirements of Section III.G 2 of Appentiix R and, Ahus alternative shutdown will be provided
, or an exe=ption from the requirements of Section III.G.2 of Appendix R will be
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Additionally provida a statscaat that all other armas of the plar.5
.are or d11 be in cc=pliance hth Section III.G.2 of Appendix R.
For each of those fire areas of the plant requiring an alternative shutdown
.syste(s) provide a cenplate set of responses to the following requests for each fire area:
- a. list the systam(s) or portions thereaf used to provide tie shutdown capability with the loss of offsite power.
- b. for those systa=s ' identified in 'Is" for which alternative or dedicated j
.shutdcwn capability saast be provided, list the equipment and compenents i
of the normal shutdowo system in the fire area and identiff the functions
,4of the circuits of the armal shutdown. system in the fire area (power to wha equipment, control of whai cm::ponents and instrument.a. tion). eDescribe the :systam(s) or portions thereof used to provide the Alternative shutdown ypability for the f. ire area and provide a table that lists the equipcient end co=ponents of the alternative shutdown system for the fire area.
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.For each alternative system identify the function of the new circuits being provided. (dentify the location (fire zone) ob the
- alternative shutdown equipment and/o'r circuits that bypass-the fire -
earea.and verify that the alternative shutdown equipment and/or circuits a
are separated frca the' fire area in accordance with Sectfen III.S.2.
Provide drawings of the alternative shutdown systam(s) which highlight ar c.
connections to the normal shutdown systems (P& ids for piping ano componen-elementary wiring diagra;cs of elec'tri' cal cabling,. Show the electrical
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location of all breakers for power cables, and isolation devices for control and inst umentation circuits for the alternative shutdown systems for that fire area.
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Verify that changes 'to safety systems wi]1 not degrade safety (e.g., new isolatforr switches and control switches should criteria and standards in'the FSAR for electrical equipoent in that the switch is to be installed; c&binets that the ' switches are e
mounted in should also meet the same criteria (ESAR) as other s related cabinets and panels; to avoid inadvertent isolation from th
. control room, the isolation switches shoul.d be keylocked or alarned -
in the control room if in the ". local." or "isolated" pesition; perio c
checks should be mAde to verify that the switch:is in the proper posit normal operatien; and a ' single transfer switch or other new device should
'at be a source of a failure which'causes loss of renuncant ufsty 4 eystams).'
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Warify that licensee procedures Anwe 4een.oNwHi be develop dasks to be perfonned to effect the shutdown method., Provide
,cf these procedures outlining. operator actions.
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Verify that the aanpower required.to perfom the snutdos
, the. procedures o'f es as well as to provide fire brigade m the fire is available as required by the fire brigade technical spe fications.
S. : Provide a cosnitment to perform adequate acceptance tests o j
native shutdown capability. These' tests should verify that:equipment.
. operates from the, local control station when the. transfer or isolatio g..
switch is placed in,.the.'Jocal" position and' that' the equi;nent c sperated from the control room; ud that equipment operates from the
. control room bus cannot be operated at the local control station whe the transfer i~ olation switch is in the "remote" position.
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- h. Provide Technical Specificat, ions of the, surveil'ance requirem
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. limiting conditions for operation for that squipment not already
. covered by existing Technical Specifications.
g For, example, if new i,
, isolation and control switches are added to a shutdown system,
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the existing Technical Specific;gt,fon surveillance requirments shou s
. be supplemented to verify systam/ equipment functions from the altemate 1
shutdown station.at testing intervals consistent with the guidelines of 4tesulatory Guire 1.22 and.1EEI 338, 4redit aay be taken for other existing desti using group. overlap test concepts.
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For_ new equipment co=prising the alteraative shutdown capability. *erify that_ the systems available are adequate to perform the necessary. shut-
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t down function.
The functions required should be based on previous analyses, if possible (e.g.
in the TSAR), such as a loss of nonnal ac
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1 power or shutdown on Group 1 isolation (SWR). The equipment required for the alternative capability should be the same or equivalent to that relied on in the above analysis.
,j. Verify that repair procedures for cold shutdown systaa are developed..
end material for repairs is maintained on site. Provide a summary of these procedures.and a list of the material needed for repairs.
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