TXX-9725, Submits Suppl to Responses Re Thermo-Lag Raceway Enclosed Thermal Mass Open Item Issues Discussed at 971112 Meeting W/Nrc

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Submits Suppl to Responses Re Thermo-Lag Raceway Enclosed Thermal Mass Open Item Issues Discussed at 971112 Meeting W/Nrc
ML20203F685
Person / Time
Site: Comanche Peak Luminant icon.png
Issue date: 12/10/1997
From: Terry C
TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TXX-97252, NUDOCS 9712170444
Download: ML20203F685 (14)
v • d • e


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-- Log # TXX-97252 P ""

~ File # 10010 5

909.5 Ref. # 10CFR50.48 illELECTRIC*

December 10, 1997 C. I.ance Terry Gnar M tmuere i U. S. Nuclear Regulatory Ccm ission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES) - UNIT I DOCKET N0, 50 445 THERMO LAG RACEWAY ENCLOSED THERMAL MASS OPEN ITEM (TAC NO M85536)

REF: 1) NRC letter from Mr. Timothy J. Polich to Mr. C. Lance Terry dated October 1, 1997

2) TU Electric letter logged TXX-97216. from Mr. C. Lance Terry, to NRC dated November 6, 1997 In response to NRC letter from Mr. Timothy J. Polich to Mr. C. Lance Terry dated i October 1, 1907 (Reference 1), TV Electric provided the information via Reference 2.

On November 12, 1997 TU Electric held a meeting with the NRC Staff at Rockville, MD., to discuss responses to open items logged via Reference 2. During this meeting TU Electric discussed Open Items 1, 3, and 4 (please refer to both references). With respect to these Open items TU Electric wishes to supplement its responses.

Open item 1 Raceway at CPSES Unit 1 where the total enclosed thermal mass is less than the total enclosed thermal mass of the tested configurations.

Response

5 TU Electric believes thit the evaiuation performed as described in Reference 2 demonstrated that thermal mass below values utilized in previous fire tests will Cl I }

not adversely impact the functionality of the cables nor adversely affect the .]hDh aoility of these barriers to perform their design function, Notwithstanding, subsequent to the November 12. 1997, meeting, TV Electric has opted to perform an

" Informational / Confirmatory Fire Test." The test will contain the following raceway-9712170444 971210

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P.O Box 1002 Glen Rome Texas 76043

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TXX-97252

.Page 2.of 3' comoditics: two 2 inch conduits and three 12 inch X 4 inch wide cable trays.

The new " Informational / Confirmatory Test" will demonstrate new lower bound thermal-mass loading values for the configurations tested. Any raceway installed in CPSES Unit 1 which has less thermal mass than this new test, will be upgraded to a 3 configuration that has been previously tested and found acceptable by the NRC for Unit 2 via NUREG 0797 Supplement 26 and 27.

These test specimens will be fabricated using TV Electric stock material similar to as installed configurations for a specific limited application of 12 inch cable tray and 2 inch conduit configurations at CPSES Unit 1. The fire test will be performed at Omega Point Laboratories (OPL). TV Electric will utilize test and acceptance criteria specified in NRC letcer dated October 29, 1992, and as modified via NUREG 0797, Supplements 26 and 27. Specifically. Insulation Resistance (megger) testing '

will be performed before and after the fire test (please refer to page 9-4 of NUREG 0797 Supplement 27), and not during the fire test. Monitoring of circuit continuity will be omitted, and fog nozzle application will be used in lieu of straight hose stream testing. Please refer to Attachment 2 cf this letter for the test plan and enclosed test article assembly configurations.

OVERVIEW 0F THE TEST The fire endurance test proposed by TV Electric is intended to obtain temperature data for Thermo-Lag raceway barriers representative of the limited population of Unit 1 configurations installed on 12 inch wide cable trays and 2 inch diameter conduits containing cable fills of 5.6 % in the 12 inch cable trays and 8.3 in the 2-inch conduit. Additionally, the proposed test will evaluate the acceptability of Dow Corning 3-6548 silicone RTV foam material as a means for sealing terminations of Thermo-Lag barrier coverage on cable trays (i.e., fire stops). TV Electric wishes the Staff to note that, except at specific locations, such as cable tray tee sections and condulet fitting enclosures and radial bends, the barrier systems installed on 12 inch cable trays and 2 inch conduits for Unit I have not been upgraded, and therefore differ significantly from the corresponding Unit 2 configurations. Specifically, all Thermo-Lag protective envelopes installed on cable trays in Unit 2, including 12 inch wide trays, are reinforced in joint areas with either tie wire " stitching" techn1gues, or a layer of external stress skin and Thermo Lag 330-1 trowel grade material. Additionally, all barriers installed on 2 inch diameter and smaller conduits for Unit 2 have been upgraded via use of preformed " overlay" sections to increase the installed barrier thickness by a minimum of k inch. A comparison matrix of Unit 1 barrier configurations with previously accepted tests and status of Unit 1 installed configurations is being provided for your review. Additionally, this matrix reflects that most of the installed configurations in Unit 1 have been upgraded and are certified using Unit 2 tests (see Attachment 1). TU Electric has concluded that this new " Informational /

Confirmatory Test" does not reflect conditions as installed and accepted by the NRC in CPSES Unit 2. and that this new " Informational / Confirmatory Test" will therefore i

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TXX-97252

,Page 3.of 3 have no affect on previous conclusions and Staff acceptance of CPSES Unit 2 installations as documented via NUREG 0797. Supplements 26 and 27.

Ooen Item 3:

Thermo-Lag fire stops installed in cable trays at CPSES Unit 1.

Response

The response to this open item was provided via reference 2. TU Electric believes that the information provided via this reference fully addresses the open item.

Open Item 4:

Silicone foam fire stops installed in cable trays at CPSES Unit 1, where the qualification is based on fire tests that used silicone elastomer.

Response

As stated in the response to Open item 1. TV Electric will test a silicone foam fire stop to demonstrate the acceptability of this material for fire stop configurations at CPSES Unit 1. Refer to the attachments to this letter for detailed configuration and test method.

Should you have any questions or need additional information, please contact Obaid Bhatty at (817) 897-5839.

Sincerely, e

C. L. Ter y 08:ob Attachments-Enclosure cc:. Mr. E. W. Merschoff. Region IV Mr. J. 1. Tapia. Region IV Mr. T. J. Polich, NRR Resident inspectors. CPSES I

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o Attachment 1 to TXX-97252 4- Page 1 of 4.

COMPARIS0N OF LMIT 1. INSTALLATIONS WITH PREVIOUSLY' ACCEPTED TESTS AND STATUS OF LMIT 1 INSTALLED CONFIGURATIONS 1

CONDUITS ACCEPTANCE UNIT 1 ACCEPTED BY NRC i COMMODITY TEST INSTALLATION VIA REMARKS I

STATUS 3/4"- UNIT 2 UPGRADES COMPLETE NUREG 0797 N/A (Schene 9-1) SUPPLEMENT 26 1* UNIT 2 UPGRADES COMPLETE NUREG 0797 N/A (Scheme 9-1) SUPPLEMENT 26 j 1-1/2" UNIT 2 PARTIAL UPGRADES NUREG 0797 WILL BE UPGPADED WITH 1/4" --

(Scheme 9-1) COMPLETE 1 SUPPLEMENT 26 PREFORMED OVERLAYS VIA J DM-97-014 2* UNIT 1 W/ CABLE PARTIAL UPGRADES SAFETY EVALUATION 1) COCUITS WITH LESS THAN'8.3 i' FUNCTIONALITY COMPLETE 2 BY NRC STAFF FILLS WILL BE LKI<ADED VIA D4-EVAL. DATED MAY 22. 97-014: 2) PROPOSED TEST SCHEME 13-3 WILL ADDRESS FILLS a 8.3 *

(Scheme 13-2) 19 %

BUT s 39.822. 3) FILL . a 39.82%

HA F "'J PREVIOUSLY ACCEPTED BY THE NRC IN MAY 22. 1996 LETTER 3' & LARGER UNIT 2 UPGRADES COMPLETE 2 NUREG 0797 N/A (Schemes 9-1. SUPPLEMENT 26 10-1 & 10-2)-

!'AllradialbendsupgradedwithstainlesssteelmeshbaSedonUnit1TestScheme.13-'2 W

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1 Attachment 1 to TXX-97252

Page 2 of 4 CONPARISON OF LHIT 1 INSTALLATIONS WITH PREVIOUSLY

' ACCEPTED TESTS AND STATUS OF UNIT 1 INSTALLED CONFIGURATIONS CABLE TRAYS ,

ACCEPTANCE UNIT 1 ACCEPTED BY COMMODITY TEST INSTALLATION NRC VIA. REPARKS STATUS l 12' ' UNIT I PARTIAL UPGRADES SAFETY 1) CABLES TRAY TEE SECTIONS UPG7ADED BASED l (SdtEME 13-2) COMPLETE EVALUATION BY ON UNIT 2 TEST SCHEME 14-1: 2) TRAYS WITH NRC STAFF DATED LESS THAN 5.63 FILL WILL BE UPGRADED VIA EM-97-014: 3) PROPOSED TEST SCHEME 13-3 PAY 22.1996 WILL ADDRESS FILLS 2 5.6% BUT s 14.6%

4) FILLS 2 14.683 HAVE BEEN PREVIOUSLY ACCEPTED BY THE NRC IN MAY 22, 1996 LETTER 18' UNIT I UPGRADES COMPLETE SAFETY N/A (SCHEME 11-5) EVALUATION BY NRC STAFF DATED i MAY 22. 1996 .i i

, 24' UNIT 1 UPCRADES COMPLETE , SAFETY N/A e (SCHEFE 11-5) EVALUATION BY NRC STAFF DATED

MAY 22. 1996 30' UNIT 2 UPCPADES COMPLETE NUREG 0797 N/A-(SCHEME 14-1) SUPPLEMENT 26 9

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Attachment I to TXX-97252 Page 3 of 4 COMPARIS0N OF UNIT 1 INSTALLATIONS WITH PREVIOUSLY ACCEPTED TESTS AND STATUS OF UNIT 1 INSTALLED CONFIGURATIONS -

l-l CABLE TRAYS (CONTD.)

4 3- ACCEPTANCE UNIT 1 ACCEPTED BY NRC

, COMMODITY TEST INSTALLATION VIA. REMARKS

j. STATUS 36" UNIT 2- N/A NUREG 0797 NOT APPLICABLE FOR UNIT 1 THE (SCHEME 15-1) SUPPLEMENT 27 .:SSA CABLES WERE RE-PaJTED IN SMALLER TRAY OR CONDUITS FIRE STOPS UNIT 2 1) SAPI AS UNIT 2 ACCEPTABLE INSTALLED FIRE STOPS CONSTRUCTED ,

(SCHEMI 14-1) FOR SILICONE SILICONE WITH SILICONE F3AH WILL BE ,

UNIT'l ELASTOMER ELASTOMER AND ADDRESSED VIA PROPOSED TEST (SCHEME 11-2) 2) THERMO-LAG FIRE THERMO-LAG SCHEME 13 NEI TEST 2-8 STOPS INSTALLED AS CDNFIGURATIONS TESTED VIA NEI TEST 3

3) SEE REPARKS FOR SAFETY EVALUATION ,

INSTALLED SILICONE BY NRC STAFF FIRE STOPS DATED PAY 22.

19 %

CABLES- UNIT 1 UPCRADES COMPLETE SAFETY EVALUATION THREE LAYE.P,5 0F FLEXI-BLANKET WRAPPED IN (SCHEFf 15-2) BY NRC STAFF (330-660) INSTALLED EXPOSED DATED MAY 22.

TRAY 19 %

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COMPARISON OF UNIT 1 INSTALLATIONS WITH PREVIOUSLY j- ACCEPTED TESTS AND STATUS OF UNIT 1 INSTALLED CONFIGURATIONS AIR 0ROPS  ;

4 ACCEPTANCE - UNIT 1 ACCEPTED BY COMMODITY TEST IN:TALLATION NRC VIA REPARKS r STATUS LESS THAN' ' UNIT 2- UPGRADES COMPLETE NUREG 0797 N/A 1-1/2" (SCHEME 11-1) SUPPLEMENT 26 i' 1-1/2" UNIT 2 TO BE UPGRADED NUREG 0797 1) ACCEPTABLE VIA NRC LETTER (SCHEME 11-1) SAME AS UNIT 2 SUPPLEMENT 26 DATED NOVEMBER 6. 1997 4

2) THREE LAYERS OF FLEXI-BLANKET (330-660) WILL BE l INSTALLED VIA DM-97-014-r 2" UNIT 2 TO BE UPCRADED PUREG 0797 1) ACCEPTABLE VIA NRC LETTER (SCHEME 11-1) SAME AS UNIT 2 SUPPLEMENT 26 DATED NOVEMBER 6. 1997

- 2) THREE LAYERS OF FLEXI-I BLANKET (330-660)'WILL BE.

i INSTALLED VIA DM-97-014 <

,, 3* & LARGER UNIT 2- UPCRADES COMPLETE PCREG 0797 N/A (SCHEME 11-1) SUPPLEMENT 26 L

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Attachment 2 to TXX 97252 Page 1 of 2 ONE HOUR FIRE ENDURANCE TEST OF ARTICLES PROTECTED WITH THE THERMO-LAG FIRE BARRIER SYSTEM 1.0 SCOPE This test plan describes the methods and guidelines to be utilized for the preparation of test specimens. installation of the Thermo-Lag Fire Barrier Systems, performance of fire endurance and hose stream tests, insulation resistance testing and temperature monitoring, and all applicable documentation of these tasks and the test results.

2.0 OBJECTIVE The_ fire endurance test proposed by TV Electric is intended to obtain temperature data for Thermo Lag raceway barriers representative of the limited population of Unit 1 configurations-installed on 12 inch wide cable trays and 2 inch diameter conduits containing cable fills of equal or greater than 5,6 % in the 12 inch cable trays and cable fills of equal or greater than 8.3 % in the 2-inch condult. Additionally, the proposed test will evaluate the acceptability of Dow Corning 3 6548 silicone RTV foam material as a means for sealing terminations of Thermo Lag barrier coverage on cable trays (i.e. , fire stops).

This test will be performed using the ASTM E119-88 fire exposure for a period of one hour, followed by a hose stream test. This test will be performed using the criteria, as detailed in the NRC Letter dated October 29, 1992. (enclosed), with the exception that cable circuit integrity will not be monitored during the test or utilized in the test acceptance basis. In the absence of other standards for these specific types of tests, standard practice shall be invoked. Variations in this test procedure from these methods will be documented in the final test report.

3.0 ACCEPTANCE CRITERIA 3.1 Temperature - Cable tray side rail temperatures and conduit external temperatures will be monitored with thermocouples. In addition, thermocouples on one of each cable type (power, control, instrumentation) will be averaged (where applicable). Acceptance criteria maximum temperatures will be 250*F above the ambient initial temperature, for averages as listed above and 325"F above the ambient initial temperature, for any single thermocouple.

3.2 Hose Stream Test / Barrier Inspection - A hose stream test with 30' fog nozz h at 75 psi minimum pressure and 75 gpm minimum flow will be applied to the test assembly from a distance of five feet away for five minutes.

Following the hose stream test, a visual inspection will be conducted to document any evidence of burnthrough or opening of the barrier by the hose stream. Acceptance criteria requ1res that no evidence of burnthrough or openings in the barrier are identified such that the raceway or cables are

Attachment 2 to TXX-97252 Page 2 of 2 visible.

3.3 Cable Visual Inspection - Providing items 3.1 and 3.2 are satisfactory.

cable visual inspection is not required. However, if either of these criteria are not met, the barrier material will be removed and the cables will be inspected visually for damage based on inspection attributes described in the NRC letter dated October 29, 1992. Documentation of cable visual condition will support cable functionality testing in 3.4.

3.4 Insulation Resistance Testing - Providing items 3.1 and 3.2 are satisfactory, insulation resistance (IR) testing is not required. However, if either of these criteria are not met, the barrier material will be removed and IR testing shall commence within thirty (30) minutes following the hose stream test. Following completion of IR testing, cable visual inspection (item 3.3) shall be performed. During the barrier visual inspection and prior to thirty minutes following the hose stream test.

insulation resistance testing will be conducted using the formula for acceptance criteria in the NRC Letter dated October 29, 1992. Providing the results meet those values. the test will be considered satisfactory.

Test SEQu2DCe Bu11d Sample 4 4 4 4 Fire Test 4 4 4 4 Fog Nozzle Test Megger Temperature Post Test Megger Measurement Fire Barrier Inspection Visual Cable Inspection

ENCLOSURE 1 TO TXX-97252 "SKETCIIES OF TEST ASSEMBLY" i

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9 ENCLOSURE 2 TO TXX-97252 "NRC LETTER DATED OCTOllER 29,1992" l

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lt** c UNITED STATES 5

I NUCLEAR REGULATORY COMMISSION WASHINoToN, D.C. 20585 o,,

          • October 29, 1992 Docket No. 50-446 Mr. William J. Cahill, Jr. Q ',C C' 'E'l 11 :

Grou Vice President, Nuclear TU E ectric $'e , , E, 400 North Olive Street, L.B. 81

  • Dallas, Texas 75201 Vd, L% s. UltHul. JK Daar Mr. Cahill:

SUBJECT:

THERMO-LAG ACCEPTANCE METHODOLOGY FOR C0KANCHE PEAX STEAM ELECTRIC STATION - UNIT 2 The NRC staff has completed a review of TU Electric's submittal dated September 24, 1992, " Confirmatory Testing of Thermo-Lag Fire Barrier System at CPSES." A meeting was held on October 27, 1992 between NRC and TV Electric, where you updated your fire barrier testing acceptance criteria. The enclosure to this letter provides the revised acceptance criteria you proposed at that meeting.

This letter informs you of the results of the staff review of your criteria.

Final NRC staff review of your fire barrier acceptance testing will be documented in a future safety evaluation.

Your acceptance criteria, including the use of a fog hose stream test in accordance with NUREG-0800, is acceptable based on the following conditions:

1. The NRC maintains that the temperature meat ' 'n the external surface of the raceway should not exceed 325*F. Your crit i + submitted in your September 24,1992 let maintained below 325*F,ter, states that cable temper = ores are to beas m inch intervals on cables close to the inside of the protective envelope.

In your previous tests, the raceway, in addition to the cables, was instrumented with thermocouples. These thermocouples provide a better indication of barrier unexposed side thermal performance during the fire test. You have stated that you will be mor.itoring various raceway locations in these upcoming tests;-however, in reviewing your criteria as submitted in your September 24, 1992 letter, we could not determine how

> you propose to evaluate the barrier's thermal performance using the raceway thermocouples.

' The 325'F temperature condition was established by allowing the internal temperature on the raceway surface to rise 250*F above ambient laboratory air temperatore, assumed to be 75 F, during the fire test..

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- Mr. William J. Cahill, Jr. '

In the October 27, 1992 meating, we discussed this concern and your staff l

' indicated that the cable tray side rail and the external conduit temperatures would be used to determine the temperature acce)tance of the '

fire barrier system. In addition, your-staff agreed, for ca)1e trays, to also use the cable thermocouple temperature readings to supplement the raceway thermocouples in assessing the thermal performance of the fire barrier system.

With respect to determining the temperature acceptance criteria, the NRC staff considers thermocouple averaging aci.eptable, provided similar series of thermocouples (e.g., cable tray side rail) are averaged together. It '

was determined that the temperature performance of the cable tray fire barrier would be based on temperature averages (i.e., the thermocouples on each side rail, and the thermocouples on each of the three instrumented cables) and would be independently evaluated against the temperature

  • acceptance criteria. In addition, it was agreed that averaging the thermocosples on the external conduit-surface would be used to evaluate the thermal performance of the conduit fire barrier system. It is our understanding that your temperature acceptance _ criteria would find the test results in deviation if the average temperr.ture of any thermocouple series exceeds the 250'F plus ambient condition or if any single thermocouple exceeds 30 percent above the maximum allowable temperature rise (i.e., 250'F + 75'F = 325'F, above ambient) during the test. If this occurs, under your criteria a visual inspection of the cables for signs of thermal damage is required. Any sign of thermal cable damage would be a deviation to the fire barrier requirements which would require the functionality of the cabling to be demonstrated by testing.
2. Your barrier inspection criteria, submitted in your September 24, 1992 latter, allows burnthrough no greater than one-half square inch. In the October 27, 1992 meeting, your staff rev; sed its position on burnthrough.

In this meeting your staff indicated that any burnthrough is now a deviation requiring cable -functionality testing. If burnthrough occurs, based upon visual examination and notwithstanding the size of the defect, the NRC views the fire barrier as devisting from the fire barrier requirements and would require that cable functionality be demonstrated.

3. Your visual cable acceptance criteria, submitted in your September 24, 1992 letter, stated that none of the following :ttributes should be identified: jacket swelling, splitting, or discoloration; shield exposed; or jacket hardening. The NRC staff has detained that the following i attributes also indicate thermal degradation: Jacket blistering, cracking or melting; conductor insulation exposed, degraded, or discolored; and bare copper conductor exposed. It is ou.' understanding that your criteria for visual cable acceptance will in:1ude all of the above attributes.

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Mr. William J. Cahill, Jr. . .

4. Your acceptance methodology calls for a megger test after the cable has been installed in the raceway, continuity measurements during the test, and a subsequent megger test immediately following the test. At the October 27, 1992 meeting, you provided additional details and clarification regarding your proposed testing to demonstrate cable functionality. Additionally, you stated that you may use loss-of-coolant-accident (LOCA) cable qualification test results in evaluating cable functionality at elevated temperatures. .

At the October 27, 1992 meeting, the' NRC staff described the following tests which can be used to demonstrate functional performance of cables where there are signs of thermal damage to cables or where barrier burnthrough or opanings occur:

The megger tests (pre-fire, during the fire (if perfwrmed), and immediately after the fire test conditions) should be done conductor-to-conductor for multiconductor and conductor-to-ground for all cables.

The minimum acceptable insulation resistance (IR) value, using the test voltage values for various system voltages is determined by using the following expression:

IR (Mega-ohms) 2 f r(1 Meca-ohm oer KV) + 11

  • 1000(ft))

Length (ft)

In addition, an AC or DC high potential (Hi-Pot) test for power cables greater than 1000 volts should be performed after the post fire megger tests to assest the dielectric strength. This test provides assurance that the cable will withstand the applied voltage during and after a fire. The high potential test should be )erformed for a five minute duration at 60 percent of eitler 80 volts / mil AC or 240 volts / mil DC (e.g.,125 mil conductor insulation thickness X 240 volts DC X 60% - 18,000 yde).

The table below summarizes the megger and Hi-Pot test voltages which, when applied to power, control and instrumentation cables, would con stitute an acceptable cable functionality test.

OPERATING MEGGER TEST HIGH POTENTIAL i Iyff VOLTAGES VOLTAGE TEST VOLTAGE 2,1000 volts 2500 VDC 60% x 80 V/ mil (AC)

POWER 60% x 240 V/ mil (DC)

< 1000 volts 1500 VDC NONE INSTRUMENT- $ 250 vde 500 VDC NONE AND CONTROL s 120 vac

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- Mr. William J. Cahill, Jr. '

In addition, at time intervals (at least once) during your one-hour fire exposure test, a megger test should be performed for instrumentation cables in order to assure.

that the cable will maintain sufficient '.nsulation resistance levels necessary for proper operation of instruments. LOCA temperature profiles may be used to evaluate cable funationality instead of megger testing during the fire test. If this approach is taken, you ,

should ensure that the LOCA temperatures bound the fire tercerature profile, by including cable operating temoeratures. Additionally, in determining the insulation res'istann levels required for nuclear instrumentation cables, an assessment of the minimum insulation resistance value (e.g., one mega-ohm) and its potential impact on the functionali:y C these cables should be evaluated.

The NRC concludes that performance of your proposed testing, with the additional megger and Hi-Pot testin described above, would constitute an acceptable set of tests to demonstrate that any fire barrier test deviations, should they occur, will not affect the capability of the protected cable tc perform its r,afety function. Other tests or combination of tests for cable functionality, different from these described above, would require NRC review and approval.

5. Discussions with your staff indichte that CPSES power and instrument cable meets IEEE-383 and is all-thermoset insulation type. Additionally, you have stated that installation procedures prohibit cabling to extend above cable tray side rails. When you submit your next test summary, confirm these facts in writing.

In summary, your criteria, as supplemented with the above conditions, ensures that adequate cable and barrier tests will be performed. Satisfactory results from these tests (raceway / cable temperature <325'F and no barrier burnthrough) constitutes a sat % factory bcsis- for rated fire barrier qualification. Where the temperature criteria is not met and cable inspection criteria results..in deviation (s), and/or barrier inspection results in deviation (s), your criteria calls for subsequent cable functionality testing. Also, as discussed at the October 27, 1992 meeting, since no cabling greater than 1000 volts is being subjected to the fire tests, additional testing would be required on this

, viltage class to demonstrate functionality should test deviations warrant cable functionality verifications. NRC review of your test deviation (s),

i should they occur, will be included in the staff's safety evaluation of your fire barrier acceptance testing.

Mr. William J. Cahill, Jr.. -S-The NRC staff plans on observing your upcoming testing. Further, we request that you meet with the NRC following complation.of this next set of testing to review test results.

Sinccrely, hV 0-.hN Suzanne C. Black,~ Director Project Directorate IV-2 Division of Reactor Projects III/IV/V Office of Nuclear Reactor Regulation

Enclosure:

TU Revised Acceptance Criteria cc w/ enclosure:

See next page k

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Mr. William J. Cahill, Jr. . .

-cc w/ enclosure: Jack R. Newman, Esq.

Senior Resident Inspector U.S. Nuclear Regulatory Commissior. Newman & Holtzinger P. O. Box 2029 1615 L Street, N.W.

Granbury, Texas 76048 Suite 1000 Washington, D. C. 20036 Regional Administrator, Region IV ~

U.S. Nuclear Regulatory Commissio,1 Chief, Texsi Bureau of Radiation Control 611 Ryan Plaza Drive, Suite 1000 Texa; Department of Health Arlington, Texas 76011 1100 West 49th Street Austin, Texas 78756 Mrs. Juanita Ellis, President Citizens Association for Sound Energy Honorable Dale McPherson 1426 South Polk County Judge Dallas, Texas 75224 P. O. Box 851 Glen Rose, Texas 76043 Owen L. Thero, President

_ Quality Technology Company Lakeview Mobile Home Park, Lot 35 4793 East loop 820 South Fort Worth, Texas 76119 Mr. Roger D. Walker, Manager Regulatory Affairs for Nuclear Engineering Organization Texas Utilities Electric Company 400 North Olive Street, L.B. 81

-Dallas, Texas 75201 Texas Utilities Electric Company c/o Bethesda Licensing 3 Metro Center, Suite 610 Bethesda, Maryland 20814 William A. Burchette, Esq.

Counsel for Tex-La Electric Cooperative of Texas Jorden, Schulte, & Burchette 1025 Thomas Jefferson Street, N.W.

Washington, D.C. 20007 GDS Associates, Inc.

Suite 720 1850 Parkway Place Marietta, Georgia 30067-8237

Enclosure IcstSeouence Build Sampic Megger --

Temperawe Fire Test Measure AC W Sat '

Conduit / Cable Tray Continuity < Amb + 250 F avg Temperature < Amb + 325 F peak Fog NozzelTest Hot Megger Fire BarrierInspection PotentialDeviation y

Functionality Tests *  !

Visual Cable Inspection

  • l Post Fire Sat Visual Cable Inspection Sat  : F m BarrierInspection
  • If Required No BurnThrough if  ;

Potential Deviation 1

Test Sat Potential Deviation ,

Cable Functionality _

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Verdication n Sat 6

Enclosure .

CABLE FUNCTIONALITY TESTING -

TEST SEQUENCE TU ELECTRIC PROPOSAL JUSTIFICATION DURING FIRE CONTINUITY TEST AT 12VDC -

UL 1724 RECOMMENDS THAT LOW VOLTAGE TEST SilOULD BE USED ON CIRCUIT DURING FIRE TESTING LABORATORY PERSONNEL SAFET Y REQUIREMENTS LOGISTICS OF MEGGERING ALL CONDUCTORS  ;

DURING Tile ONE IfOUR FIRE TEST RESTRICTS INTERMITTENT TFSTING

- FUNCTIONALITY OF CABLE AT ELEVATED TEMPERATURE MAY BE-CONFIRMED BY LOCA Tr.ST RESUL'IS PROVIDED CABLE JACKET TEMPERATURES DID NOT EXCEED 1.OCA QUALIFICATION TEMPERATURES AITER llOST IIOT MEGGER TEST -

ACCEPTANCE CRITERIA BASED ON MOST LIMITING STREAM TEST INSTALLATION (5 M )

- INSTRUMENTATION CABLE -

ACCEPTANCE CRITERIA FOR CONTROL / LOW '

586VDC VOLTAGE CABLE BASED ON DC EQUIVALENT TEST VOLTAGES OF RATED AC VOLTAGE (150GVDC)

CONTROL / LOW '?OLTAGE g CABLE AT 1500VU i

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