ML20057A378
| ML20057A378 | |
| Person / Time | |
|---|---|
| Issue date: | 08/31/1993 |
| From: | Mccracken C Office of Nuclear Reactor Regulation |
| To: | Thadani A Office of Nuclear Reactor Regulation |
| References | |
| GL-86-10, GL-92-08, GL-92-8, NUDOCS 9309140114 | |
| Download: ML20057A378 (29) | |
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,e wassiscTou. o.c. 2osssaoi August 31, 1993 MEMORANDUM FOR:
Ashok Thadani, Director i
Division of Systems Safety Analysis FROM:
Conrad McCracken, Chief Plant Systems Branch i
Division of Systems Safety Analysis
SUBJECT:
SUMARY OF AUGUST 19, 1993, MEETING BETWEEN NRC STAFF AND NUMARC ON INDUSTRY THERMO-LAG FIRE BARRIER TEST PROGRAM NRC staff met with representatives of the Nuclear Management and Resources Council (NUMARC) on August 19, 1993, to discuss NRC concerns with NUMARC's Thermo-Lag test program. These concerns were documented in my August 6, 1993, letter to A. Marion of NUMARC (Enclosure 1). The meeting was to provide a forum for the NRC and NUMARC to discuss respective positions on NUMARC's test program, focusing on technical bases. is a list of the attendees.
NUMARC provided a response to each issue presented in the August 6, 1993, lettsr. Enclosure 3 is a copy of NUMARC's handout at the meeting which sumarizes the NUMARC response. A brief summary of each issue discussed follows.
NUMARC's Decision to Proceed with Testino Prior to Receivino NRC Aareement, NUMARC explained that the NRC had expressed concerns to NUMARC on the timeliness of the test program; NUMARC referenced the May 4,1993, letter from J. Taylor of the NRC to J. Colvin of NUMARC.
In addition, NUMARC stated that the licensee's compensatory measures, specifically, fire watches, put in place in response to NRC generic communications were costing the industry an estimated $3 million per month.
Finally, NUMARC explained that the NRC test acceptance criteria in proposed generic letter 86-10, Supplement 1, are not yet finalized.
Because these criteria may not be issued for some time, NUMARC explained, they felt justified in proceeding with testing using criteria which differed from than those provided by the NRC.
i While members of the NRC agreed that a delay in the NUMARC testing would not have been desirable, they explained that the NUMARC testing criteria were less conservative than those proposed than the NRC. The NRC expressed a concern that the vast majority of licensees in their responses to Generic Letter 92-08 l
have stated that they will rely on the NUMARC test program to resolve i
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l associated with their Thermo-Lag barriers. The NRC explained that if the tests are not technically applicable, these licensees may be required to qualify their Thermo-Lag barriers on an individual basis.
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l Ashok C. Thadani l Aeolicability of Test Results. The NRC letter included a concern that NUMARC's tested installations may not adequately bound installations in the industry.
W. Rasin of NUMARC agreed that the NUMARC program does have a limited applicability, and all installations outside the test boundary will require plant-specific analyses or additional testing. Mr. Rasin stated that NUMARC believes that most licensees will have sufficient documentation on their barriers (i.e., installation details, cable tray material and type, cable fill, etc.) to apply the NUMARC test results to their installations. He l
continued that NUMARC did not want to penalize these licensees by requiring superfluous upgrades as a result of a test program designed to bound those licensees who had inferior documentation on their installations.
Later in the l
meeting, B. Bradley of NUMARC told the NRC that licensees are fully aware of l
the scope of the test program and understand that the testing program will not i
bound all of their installed configurations.
The NRC staff maintained that the final test reports may only provide limited data for the qualification of Thermo-Lag barriers installed by licensees and urged that the scope of the test program be expanded to provide the industry j
with broader generic applicability.
Thermocouple Placement. According to the testing criteria proposed by the NRC, the temperature of a bare copper conductor along the center of the bottom of a raceway is a technically sound representation of the temperature of the unexposed side of a fire barrier.
In the NUMARC test program, the copper conductor is placed along the center of the top of the raceway, directly adjacent to a cable installed in the raceway.
According to NUMARC, the approach is based on a draft of ASTM E5.11, " Standard Test Methods for Fire Tests of Fire Resistive Barrier Systems of Electrical Components", and is technically sound because the cable will not thermally shield the conductor.
The NRC staff maintained that the NRC regulations and the testing criteria in the proposed supplement to GL 86-10 are based on ASTM E-119, which requires temperature measurements at the unexposed side of the barrier, not at the interior of the enclosure.
In addition, the NRC explained that placing the thermocouples at the cable, versus in the air at the unexposed side of the barrier would result in a non-conservative representation of the temperature that cables could be exposed to if they happened to be in contact with the barrier. The NRC staff further explained that some cable trays currently installed in plants are filled in such a way that cables are in contact with some portion of the fire barrier enclosure. The staff expressed the concern that thermocouples located adjacent to cables during testing may be thermally shielded or masked and may provide inaccurate temperature readings. The staff suggested two conductors to obtain technical data needed to justify the NUMARC approach. NUMARC stated that this would change the nature of the NUMARC program to a research program and did not agree to this during the meeting.
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O Ashok C. Thadani Inclusion of Cables in Cable Trays. The NRC staff had expressed a concern about NUMARC's decision to include a 15% cable fill in test specimens for the
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purpose of providing thermal mass. NUMARC explained that they understood that the results obtained from these tests would be applicable only to those assemblies which have an equal or greater cable fill. NUMARC also explained that the thermal mass could be quantified and would not introduce uncertainties in the tests.
The NRC explained that this cable fill will be a bounding parameter and that it remained important to document specific details about the cables (size, type, etc.) installed in the test specimens.
Use of I-Beam Side Rails in Tested Trays. The NRC letter noted that NUMARC's test plan did not mention the use of these side rails, yet this design feature was witnessed by the NRC staff at the test site. NUMARC responded by explaining that only the aluminum trays had this configuration, not the steel trays, and the test plan was not intended to provide that level of detail.
l Nevertheless, NUMARC noted, they had procured the flimsiest trays available and had neglected to isolate this feature as a distinguishable parameter.
The NRC staff explained that since thermocouples are placed at the side rails, the I-beam construction would allow an air gap to exist between the thermocouples and the sides of the barrier enclosure. According to the NRC, this air gap would results in lower measured temperatures and would only be applicable to actual installation with the same design feature.
Generic Cable Functionality Testina. The NRC questioned NUMARC about the reasons for excluding cable functionality testing from the test program.
According to NUMARC, testing functionality of cables was impractical due to the diversity of cable types available and the lack of resolution of technical issues related to cable functionality testing.
The NRC staff acknowledged that cable functionality testing was an optional element of the proposed supplement to GL 86-10, but suggested that functionality testing of the cables be considered and factored into the program in case the barriers fail or the cables are damaged.
If this is done, i
the tests could still serve some purpose through the deviating condition l
provisions of the proposed NRC criteria.
l l
Multiple Conficurations. The NRC expressed a concern about the inclusion of a fire stop on a test specimen to thermally separate differing installation procedures. NUMARC explained that this was a practical approach to deriving the maximum amount of information from each test, and the application guide NUMARC plans to distribute to licensees will address the limitations inherent to this test design.
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i Ashok C. Thadani The NRC maintained that the fire stop could prevent a potential failure of test specimen and expressed the concern that the testing bias resulting from
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this deign could not be quantified.
Other Concerns. The NRC letter mentioned several other issues on which the NRC asked for more information. NUMARC representatives expressed confusion over what other information was desired and explained that the final test reports and the application guide would contain all of the necessary information. According to NUMARC, some of the details had not yet been-
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determined, and they had provided the NRC with all information they had at the time.
NUMARC's position is that the NRC proposed testing criteria are overly conservative.
In areas where the NRC and NUMARC had technical disagreements, NUMARC's position was that the testing program is not a "research project" and its plant-specific technical adequacy will be determined when the program is e
completed.
l The NRC and NUMARC expressed the desire to continue to work to resolve these issues, and the NRC staff stated that NUMARC will be informed expeditiously of any new issues that arise in the course of the NUMARC testing.
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onrad E. McCracken, Chief l
Plant Systems Branch Division of Systems Safety and Analysis
Enclosures:
As stated l
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Ashok C. Thadani cc w/ enclosures:
Mr. Joseph F. Colvin President and Chief Executive Officer Nuclear Management and Resources Council 1776 Eye Street, N.W.
Suite 300 Washington, D.C.
20006-3706 Mr. Richard Licht 3M General Offices 3M Center St. Paul, MN 55144-1000 l
Mr. Dave Haines l
Eternit, Inc.
Excelsior Industrial Park P.O. Box 679 Blandon, PA 19510-0679 Mr. Ralph Block President Promatec, Inc.
P.O. Box 309 l
Cypress, TX 77429 l
l Mr. Clifton Philpott l
Darchem Engineering l
81 West Bellvue Dr.
Pasadena, CA 91105 C. T. M. Hall Darcher Engineering Ltd.
Stillington, Stockton-on-Tees Cleveland TS21 ILB England Mr. John A. D. Maxwell Thermal Ceramics P.O. Box 923 Augusta, GA 30903 Mr. Rubin Feldman President Thermal Science, Inc.
2200 Cassens Drive i
St. Louis, MO 63026
DISTRIBUTION w/ enclosures:
DISTRIBUTION w/o enclosures:
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DATE 9/2(/93
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NUCLEAR REGULATORY COMMISSION
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l Mr. Alex Marion Manager, Technical Division Nuclear Management and Resources Council 1776 Eye Street, N.W., Suite 300 Washington, D.C. 2006-3706
Dear Mr. Marion:
l During the June 3, 1993 meeting, to address the concerns raised by Mr. James M. Taylor, Executive Director of Operation in his letter dated May 4, 1993, Mr. Joseph Colvin, President and Chief Executive Officer of Nuclear Management and Resources Council (NUMARC), indicated that they have developed a program i
l for addressing the technical issues and were working towards a solution to the industries fire barrier problems.
From this meeting, it was my understanding that NUMARC had agreed to work with the staff and have a mutual understanding and agreement of the program details prior to it's implementation.
On June 28, 1993, we met to discuss the (NUMARC's) program for resolving the fire endurance and combustibility issues associated with Thermo-Lag 330-1 fire barrier systems.
During this meeting we stated several technical issues which required additional information and technical justification.
In my July 13, 1993 letter, we expressed these technical concerns in writing. On July 26, 1993 NUMARC initiated construction of test specimens. On July 29, 1993, NUMARC responded to these technical concerns.
The staff has reviewed the NUMARC response to our request for additional information.
Enclosed are the results of this review. This review indicates that the concerns which were previously identified have not been fully l
addressed by your response. The staff has remaining concerns associated with thermocouple placement, cable fill used to improve fire barrier performance, I
lack of cable functionality testing, and based on our observations of the test specimen construction activities we have concerns regarding the placement of thermocouples on the cable tray side rails and the use of multiple fire barrier construction techniques on a single test specimen.
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The staff is concerned that the Phase i testing program acceptance criteria does not follow the fire barrier acceptance criteria recommended by Generic Letter (GL) 86-10," Implementation of Fire Protection Requirements," or the testing methodology and acceptance criteria proposed by Supplement 1 to GL 86-10. " Fire Endurance Acceptance Criteria for Fire Barrier Systems Used to Separate Redundant Safe Shutdown Trains Within the Same Fire Area." As a result of these concerns, the current Phase 1 test plan introduces uncertainties which brings doubts as to its generic applicability and the fire i
resistive functionality of the fire barrier system being tested.
To enable the staff to review the industry Thermo-Lag program and assure that J
the results of these tests can be reasonably applied on a generic basis, we request that NUMARC take the necessary actions.to resolve the staff's q
Mr. Alex Marion l technical concerns. We are prepared to meet as soon as possible to resolve these issues.
If you have any questions, please contact Mr. Steven West, at (301) SO4-1220.
I Sincerely,
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sj, Conrad E. McCracken, Thief Plant Systems Branch Division of Systems Safety and Analysis Office of Nuclear Reactor Regulation
Enclosure:
i As Stated r
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ENCLOSURE i
NUMARC THERMO-LAG 330-1 FIRE BARRIER TESTING PROGRAM j
STAFF'S EVALUATION OF THE JULY 29, 1993 SUBMITTAL-On June 22, 1993, NUMARC submitted Phase 1 of its fire test program to the NRC and on June 28, NUMARC met with the NRC staff, in a meeting open to the i
public, to discuss its plans to resolve the technical issues associated with the fire resistance and combustibility of Thermo-Lag 330-1 fire barrier material. Upon reviewing the NUMARC Thermo-Lag Phase 1 test plan and the t
information presented during the meeting, the staff concluded that several areas needed additi~"I clarification.
By letter dated July 13, 1993, the NRC l
requested this additwnal information. NUMARC, in their letter of i
July 29, 1993, provided a partial response to these questions and concerns and j
indicated that the requested additional information on the combustibility j
issues and the Phase 2 testing program would be provided at a later date.
The staff has reviewed this additional information provided by NUMARC and has i
found the following technical issues were not adequately addressed:
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I.
THERMOCOUPLE PLACEMENT AND FIRE ENDURANCE TESTING i
The method of measuring internal temperature conditions and averaging the data from thermocouples identified in the NUMARC Phase 1 test plan.
is not consistent with the proposed supplement to Generic letter (GL) 86-10, " Fire Endurance Acceptance Criteria for Fire Barrier Systems Used to Separate Redundant Safe Shutdown Trains Within the Same Fire-Area."
measure the temperatures of the unexposed surface of the_ fire' barrier.
' J The bare copper conductor instrumented with thermocouples used to l
material on the bottom of the cable tray fire barrier. assembly are-routed in the tray with the cables on top of the tray rungs and not along the bottom of the rungs as specified in the proposed supplement to GL 86-10. The fire barrier acceptance criteria guidance provided.in GL 86-10 specifies that fire barrier performance be judged on the temperature of the unexposed surface of the fire barrier material.
In addition, the NUMARC proposed location for the instrumented bare copper conductor is insulated by air and the cable jacket material.
The inclusion of cables to improve the thermal performance of these fire barrier systems introduce uncertainties as to the generic applicability of these tests to the industry. This is not an accurate measure of the thermal performance of the fire barrier.
In addition during the week of July 26, 1993, NRC staff observed NUMARC's construction activities at Omega Point Laboratories in San Antonio, Texas, and noted that the cable tray construction was not consistent with the tray construction depicted in revision 4 of the NUMARC test plan. The NRC noted that the side rails of the tray were an 1-beam in lieu of a C-channel.
In the test plan, the test specimen design details indicate that the trays are of a C-channel construction with the flat surface of the C-channel up against the fire barrier material.
This would give the impression that the cable tray side rail thermocouples are in direct contact with the fire barrier material's unexposed surface. With the I-beam tray construction that is being used by NUMARC, the cable tray side rail thermocouples are place on the web between the flanges. This introduces a V-inch insulating air gap e
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i between the thermocouple and the fire barrier material..This placement is non-conservative with respect to determining actual fire barrier performance. This air gap insulates the thermocouples and causes them to indicate temperatures which are lower than the actual unexposed fire barrier surface temperature. The staff considers this cable tray thermocouple placement proposed by NUMARC to also introduce uncertainties that may impact the generic applicability of these tests 4
to the industry.
i In their response, NUMARC indicated that the purpose of the fire test is i
to ensure cable functionality and that measurement of temperatures below the cable rungs has no relaticn to cable functionality. NUMARC's l
Phase 1 test plan does not include any provisions to perform functionality testing of the proposed cables included in the cable tray j
test specimens. NUMARC's approach is inconsistent with the proposed supplement to GL 86-10, which clearly states that the fire barrier functionality, as demonstrated by limited temperature rise, not cable functionality, is the principle objective of a fire endurance test.
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NUMARC has asserted that the NRC approval of the TV Electric acceptance criteria is an adequate basis to approve their thermocouple placements.
The staff does not agree with this assertion.
It should be noted that J
the TV approach was focused on plant specific application of the Thermo-Lag fire barrier system.
In addition, the TV Electric test specimens I
used representative cable fill conditions and plant specific cables.
The cables were conservatively instrumented with thermocouples and cables were functionality monitored using an appropriate megger testing method which was consistent with the proposed supplement'to GL 86-10.
The staff concluded that TU Electric took appropriate actions towards mlving the Thermo-Lag fire barrier technical problems for Comanche Peak Unu 2.
In addition, it should be noted that the raceway thermocouples installed on the TU Electric test specimens were in contact with the fire barrier material unexposed surface.
l The staff, from their review of the NUMARC July 29, 1993, submittal 4
concludes that NUMARC did not address the concerns identified by NRC i
i question II.B.1 and 2 and does not find the NUMARC proposed placement of the copper conductor or the side rail thermocouples equivalent in J
performance to the placement as recommended by the proposed supplement to GL 86-10.
In addition, NUMARC, in their July 29, 1993 submittal, did not propose a criterion for applying thermocouples on the cables within the cable tray test specimens.
In addition, NUMARC did not address questions on how bare cooper conductors will be routed through the junction boxes (JBs) and how cables laying up against the JB inner surface will be simulated.
NUMARC indicated that they reserve the right to terminate a particular test if observations indicate imminent breach of the barrier.
The staff considers that this type of approach can lead to indeterminate results.
From a practical testing-perspective, tests are terminated only after a.
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known failure has occurred.
From an analysis standpoint, due to the fact that NUMARC wants to include non-instrumented cables in the cable trays and not perform cable functionality testing, neglecting to include thermocouples on the cable tray side rails and the instrumented bare i
copper conductor which are in contact with the fire barrier material introduces additional uncertainties associated with the actual fire barrier performance which may lead to indeterminate results.
II.
CABLE FILL AND FUNCTIONALITY TESTS NUMARC, by their July 29, 1993 submittal, maintains that cables will be installed in cable trays because "this thermal mass is important' to the performance of the fire barrier.' The staff contends that this is not a true test of fire barrier performance. The fire barrier acceptance l
criteria recommended by the proposed supplement to GL 86-10 clearly states that the fire barrier functionality, as demonstrated by limited temperature rise, not cable functionality, is the principle obje:.'iu.
j The staff finds a true test of the barrier system and its raceway l
components to be germane to determining fire resistive performance, and j
the inclusion of a cable fill to improv fire barrier thermal performance t
l is non-conservative.
l NUMARC, in their July 29, 1993 submittal, did not address our concern l
about the internal temperature profiles being indeterminate for cable l
types and fills other than those tested. The staff finds the validity j
and the applicability of the temperature profiles derived by the NUr! ARC Phase 1 cable tray tests to be a significant technical issue.
The indeterminate results derived by these tests could create additional regulatory concerns regarding those licensees which attempt to.use the test results (temperature profiles) to evaluate in-plant barrier configurations, which have a wide range of cable fills, cable types and sizes.
For example, if a fire barrier system had no cables installed, as in the case of the TVA tests, were tested, the temperature measured on the unexposed surface of the fire barrier were maintained at or below I
the 139'C [250 'F] delta limit criterion, the data would provide clear assurance that the fire barrier performed its intended function and that this specific barrier configuration could be applied generically.
From i
the generic perspective, the TVA methodology for determining the internal raceway temperature profiles provided a sound basis for determining the thermal impact on cable functionality.
NUMARC's submittal asserted that cable functionality is a significant unresolved technical issue. The staff d W ces with this assertion.
The staff noted that while NUMARC wants in iake credit for a thermocouple placement method which the) 'ssert is equivalent to the TU method, it has elected to ignore the cabL. functionality testing methodology used by TU Electric.
l The staff finds that NUMARC's response to questions NRC questions II.D.1, 2 and 3 did not address the technical concerns.
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III. MULTIPLE ASSEMBLY / CONSTRUCTION TECHNIQUES FOR A SINGLE TEST SPECIMEN During the staff's July 26-30, 1993, observations, it was noted that NUMARC was constructing a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> Thermo-Lag fire barrier assembly on a i
35" x 4" galvanized steel ladder back cable tray (Scheme 1-3).
This
" baseline" test specimen utilized 1-inch nominal thickness "v-rib" panels with stress skin on both inner and outer surfaces. The panels l
were dry fitted and held in place by steel bands on the straight run l
portion of the tray, and the radial bends were enclosed with differing l
installation techniques. One radius was enclosed with scored panels, j
held in place by 2 steel bands on each scored section, and the other radius was enclosed with mitered pieces, held in place by.2 tie wires on each mitered section. After the dry fit enclosure was completed, NUMARC l
applied Therec-Lag 330-0 trowel grade material to the seams and joints of the prefabricated panels such that seams.and joints were completely covered.
In addition, the staff noted that a.Thermo-Lag enclosa e for Scheme 1-1, a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> " baseline" test utilizing a 36" x 4" aNminum cable tray, also included the two different installatior 9chni;aes (scoring and mitering) at the radial bends.
Testing multiple assembly and construction techniques on a single test i
specimen instead of two or more test assemblies could result in indeterminate test results and inadequate. qualification for certain fire barrier design features.
In order to demonstrate that these i
construction techniques (e.g., band spacing, seam and joint l
construction) are representative of installations which would be installed in plants, it becomes imperative to test configurations with horizontal and vertical runs. This would include testing radial tray l
bends and cable tray T-sections. The staff considers the NUMARC t
approach of testing multiple construction techniques on one test specimen to be a non-conservative fire testing qualification practice.
l IV.
OTHER ISSUES NOT ADDRESSED On July 13, 1993, the NRC requested additional information concerning the NUMARC Thermo-Lag fire barrier test program. The staff has determined that the July 29, 1993, NUMARC submittal has not adequately addressed the following technical questions from our July 13, 1993 request:
Question II.A.1 The NUMARC response did not provide clarification as to the range of raceway configurations the Phase 1 program is intended to bound and which test specimen will qualify the configuration.
Question II.A.2 In its response, NUMARC did not explain in detail the construction of Phase 1 baseline assemblies or demonstrate that the construction attributes for these baseline assemblies represent the fire barrier L l
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construction techniqc?s used to construct the barriers currently installed within the industry.
Question II.C.1 I
The NUMARC response did not quantify the thermal masses of the raceway components associated with the Phase 1 test program.
Question III.B The !.UHARC response did not explain, in detail, the procurement and receipt inspection processes and the specific responsibilities of NLMARC, ABB Impell, Omega Point Laboratories, other contractors, TSI rad other vendors, and individual licensees in these processes.
In addition, the NUHARC response did not address how these processes would be applied to all components to be used in the test program such as raceways, cables, and fire barrier materials.
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2 Meetina Attendees Hitmg Affiliation l
A. Thadani USNRC C. McCracken USNRC l
S. West USNRC A. Singh USNRC l
J. Holmes USNRC I. Miller USNRC j
W. Dean USNRC A. Pal USNRC R. Perch USNRC j
G. Mulley USNRC L. Plisco USNRC i
W. Rasin NUMARC A. Marion NUMARC B. Bradley NUMARC C. Banning ABB Impell i
R. Dible ABB Impell T. Meisenheimer Bechtel l
J. Raleigh STS, Inc.
l D. Stellfox McGraw-Hill R. Huston TVA j
C. Hunter BWNS T. Dinh HNUS l
P. Gunter NIRS l
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Endosure3
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1 l
NUMARC Thermo-Lag Testing i
Program General Issues identifiec by h RC (letter of August 6)
- NUMARC decision to proceed absent NRC i
l agreement with program details
- Variations from draft NRC Generic Letter 86-10, Supplement 1 l
- Generic Applicability of results l
NUMARC 1
NUMARC Decision to Proceed NRC concern: NUMARC proceeding absent NRC agreement wit 1 test program details, including variations from c ra"t N RC GL 86 ' 0 Sup alement '
l NUN. ARC has made a good faith e= ort to interact on acceptance criteria issues since mic-1992 Our arevious comments have not aeen incorporatec or cispositionec Latest version of proaosed criteria is unc7angec in suastance # rom Novem aer ' 992 NUMARC 2
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NUMARC Decision to Proceed Schedule for final acceptance criteria is still uncertain est and acce atance criteria issues
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cannot Je "inally resolved arior to pua ic comment period and h RC generic communications arocess Inc ustry program is consistent wit 7 arevious b UN ARC comments and general y consistent with h RC aro30sec position NUMARC 3
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l NUMARC Decision to Proceed i
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l Program sclec ule made avai aa e to NRC in June anc has aeen l
foi owed accordingly 1
i Prior NRC concern was tlat i
3rogram was not moving fast enougl 4
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Significant ongoing industry I
resource im aact i
Test 3rogram is technically sounc Business c ecision to proceed towards generic resolution NuMARC 4
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Generic Applicability h RC concern: N'UMARC program will not bounc all industry installations wit 7out some utiity-s aecific analysis Bounding of a I raceway and " ire barrier aarameters for tests woulc resu t in.
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- Tested configurations not representative of installed configurations
- Development of upgrades that greatly exceed the rc quirements of most plant installations
- Massive unjustified expenditures for installation of these upgrades NUMARC 5
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Generic Applicability i
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NUMARC program will test instal ations rearesentative of t7e l
majority of industry a a a ications i
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Upgraces will ae cevelopec accordingly i
I P ant instal ations not boundec by test aarameters will ae ac c ressec ay utiities using NU V ARC a a alication guic e ine, anc limitec inc ividual testing l
We believe t7is is the only practica a a aroac1 towarc s resolution 4
NUMARC 6
Thermocouple Placement NRC concern: Placement o" bare co oper conductor on top of, versus underneath, ca ale tray rungs NUMARC approach:
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- Consistent with Draft 8 of ASTM E5.11,
" Standard Test Methods for Fire Tests of Fire Resistive Barrier Systems of Electrical components"
- Technically sound in that temperatures are measured in locations that would contain or be in contact with cable
- Does not result in thermal shielding of conductor due to cable placement
- Conservative with respect to T/C placement criteria granted to TUEC i
NUMARC 7
Inclusion of Cables in Cable Trays N RC Concern: Inclusion o" ca ales wiI introc uce uncertainties relative to generic applicability NUM ARC Aaproac1:
- Provides for test conditions (thermal mass) representative of plant installations
- Bounds a significant majority ofindustry installations relative to thermal mass
- Does not introduce uncertainties: thermal mass can be quantified and compared to plantinstallations NUMARC 8
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Use of I-Beam Side Rails in Al Cable Trays NRC Concern: Use of I-beam sic e rails is potentially non-conservative.
i Test plan dic not provic e this detail.
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'T hote:
Only Al trays use t7e 13eam con"iguration, steel tray side rails in cirect contact wit 13arrier Test plan not intendec to provice t1is level of c etail Stancard A trays procured for test l
3rogram N.any plant installations involve larger air ga a than testec NUMARC 9
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i Generic Cable Functionality Testing l
N RC Concern:
h o generic ca ale l
j functiona ity testing I
Functionality testing is o ational j
element i
N ot practica as part of generic test 3rogram due to civerse caale types Unreso vec technical issues re ative to ca ale "unctionality testing Utiities may aer orm caale functional testing or use existing
.l cable c ata NUMARC 10
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1 Multiple Configurations i
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i i
i h RC Concern: Use of mu.tiple l
j configurations on single test articles l
i Common practice in fire testing i
I 3ractical a aproach to ac dress j
multia e con"igurations i
Industry a a alication guideline wiI l
ac c ress limitations on use o" test resu ts (e.g., unsu a aorted s aan j
distance, etc.)
NUMARC 11
1 Other NRC Concerns Eac1 was acc ressec in NUMARC's letter of July 29 or in test plan provided to NRC on June 28:
- No provisions for cable thermocouples l
- Junction box thermocouples i
- Test termination j
- Range of bounded configurations
- Baseline construction details
- Thermal masses j
- Procurement and receipt inspection process
- Division of responsibilities NUMARC 12 I
CROSS SECTION OF TEST ARTICLE CABLE TRAYS WITH "I" BEAM SIDE RAILS i
I s
i l
I 4
h 6
\\
<t 4"
4 L
q s/8"
.-m.
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W"
1 and 3 Hour Baseline Thermo-Lag Installation J
36" and 24" Cable Trays: Tests 1 - 5 e
1
,g_
i 2p Stainlese Stett Banding Stainless Steel Tie Wire Used on Right Left a-l Used On Left Leg 1-Structural Supports g ;,
kax 12" l
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- v
}
Three Hour g pg{.J b k fe5t bkM b One or Three Test Articlei w
Hour Test (fyP-)
bands AI*I*
i are used to Two (2) tie
--,,g fasten eachh
[
to fasten each wires are used scored section of radius.
l mittered sectiot
/
- n
~
~
=
of radius,
'l Il
{
i)ne Hour i
Test Article b45dl.s,JE P4*lEL % M 56$
ihr. O.500"t o.32,g " o
- One (1) band is used to l
Iasten each scored section 3 9., g,,,.+ 0.ZW - O' of radius.
i w
W
.. _ - ~ -,
. c
=
LOCATION OF BARE COPPER CONDUCTORS IN CABLE TRAY TEST ARTICLES Bare 14 AWG copper conductor on top of cable layer v
Bare 14 AWG copper conductor on top of tray rungs
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