Information Notice 1994-22, Fire Endurance & Ampacity Derating Test Results for 3-Hour Fire-Rated Thermo-Lag 330-1 Fire Barriers: Difference between revisions
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{{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555March 16, 1994NRC INFORMATION NOTICE 94-22: FIRE ENDURANCE AND AMPACITY DERATING TESTRESULTS FOR 3-HOUR FIRE-RATED THERMO-LAG 330-1FIRE BARRIERS | {{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555March 16, 1994NRC INFORMATION NOTICE 94-22: FIRE ENDURANCE AND AMPACITY DERATING TESTRESULTS FOR 3-HOUR FIRE-RATED THERMO-LAG 330-1FIRE BARRIERS | ||
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==Description of Circumstances== | ==Description of Circumstances== | ||
As part of its continuing evaluation of Thermo-Lag fire barrier performance,the NRC Office of Nuclear Reactor Regulation (NRR) conducted three full-scalefire endurance tests and one full-scale ampacity derating test of 3-hourfire-rated Thermo-Lag fire barriers. The principal objective of the tests wasto evaluate the performance of the barriers against the results of testspreviously reported by Thermal Science, Incorporated (TSI, the vendor).Sandia National Laboratories (SNL), Albuquerque, New Mexico, providedtechnical assistance by designing and executing the test program and preparingthe test report. The base test specimens were constructed and instrumented atSNL. The test specimen fire barriers were constructed at UL by trainedThermo-Lag installers under the direction of SNL during October andNovember 1993. The tests were conducted at UL under the direction of the NRCand SNL during December 1993. The NRC staff informed the Nuclear Managementand Resources Council (NUMARC) of the test results during a public meeting atNRC Headquarters on February 9, 1994. The final test results will bedocumented in SNL Report SAND94-0146, "An Evaluation of the Fire BarrierSystem Thermo-Lag 330-1." The staff will place this report in the NRC PublicDocument Room after it is completed. The staff expects the report to becompleted during April 1994._Efh-1X-9403150511 ,r.D9af aqedqij4- o,2~.3/2! 5/Y9q 0 3 1 (Il | As part of its continuing evaluation of Thermo-Lag fire barrier performance,the NRC Office of Nuclear Reactor Regulation (NRR) conducted three full-scalefire endurance tests and one full-scale ampacity derating test of 3-hourfire-rated Thermo-Lag fire barriers. The principal objective of the tests wasto evaluate the performance of the barriers against the results of testspreviously reported by Thermal Science, Incorporated (TSI, the vendor).Sandia National Laboratories (SNL), Albuquerque, New Mexico, providedtechnical assistance by designing and executing the test program and preparingthe test report. The base test specimens were constructed and instrumented atSNL. The test specimen fire barriers were constructed at UL by trainedThermo-Lag installers under the direction of SNL during October andNovember 1993. The tests were conducted at UL under the direction of the NRCand SNL during December 1993. The NRC staff informed the Nuclear Managementand Resources Council (NUMARC) of the test results during a public meeting atNRC Headquarters on February 9, 1994. The final test results will bedocumented in SNL Report SAND94-0146, "An Evaluation of the Fire BarrierSystem Thermo-Lag 330-1." The staff will place this report in the NRC PublicDocument Room after it is completed. The staff expects the report to becompleted during April 1994._Efh-1X-9403150511 ,r.D9af aqedqij4- o,2~.3/2! 5/Y9q 0 3 1 (Il | ||
<<J IN 94-22March 16, 1994 DiscussionEach of the four base test articles was a U-shaped configuration layingsideways which duplicated configurations, material specifications, dimensions,orientations, cable types and fills, and instrumentation, previously testedand reported by the vendor. A single layer of cables was installed in each ofthe fire test articles in accordance with the types and placements reported inthe vendor's test reports. The cable fill for the ampacity derating testarticle is discussed under the "Ampacity Derating Test" section of thisinformation notice.Each of the base test articles was protected by a 3-hour fire barrier formedfrom two layers of nominal 3/4-inch-thick Thermo-Lag 330-1 preformed panel. SNLpurchased the Thermo-Lag preformed panels and trowel-grade material used toconstruct the test article fire barriers from Texas Utilities Electric Company(TU Electric). TU Electric performed a source inspection of the materials atTSI and the NRR Vendor Inspection Branch conducted a receipt inspection of thematerials at the Comanche Peak Steam Electric Station when TU Electricdelivered the materials to SNL.The fire barriers for Test Articles 1, 2, and 4, were constructed inaccordance with TSI Technical Note 20684, Revision V, "Thermo-Lag 330 FireBarrier System Installation Procedures Manual Power Generating PlantApplication," November 1985. The fire barrier for Test Article 3 wasconstructed in accordance with the methods used by the vendor for TestArticle 4 of TSI Report 82-11-81, "Three Hour Fire Endurance Tests Conductedon Test Articles Containing Generic Cables Protected with the Thermo-Lag 330-1Subliming Coating Envelope System," November 1982. Table I summarizes thetest article characteristics.The stress skin (an embedded wire mesh) for the inner barrier layer facedtoward the cable tray. The stress skin for the outer layer faced away fromthe cable tray. All joints and seams were offset. The edges of theindividual panel sections were buttered with trowel-grade Thermo-Lag 330-1material before they were joined and secured. This assembly technique, asopposed to the dry-fit method, ensured that each Joint and seam was filled toits full thickness with Thermo-Lag material. The individual barrier piecesfor Test Articles 1, 2, and 4 were banded with stainless steel tie wire. Theindividual pieces for Test Article 3 were not banded. Instead, each seam andjoint was reinforced with stainless steel wire stitches and laces. Inaddition, flanges were formed along the edges and butt Joints of the outerlayer. The flanges were bolted together with nominal k-inch-20 by 2-inchmachine bolts and hex-nuts. After the barriers were installed, the testarticles were cured for at least 30 days in a secure temperature-controlledenvironment before the tests were conducted.The instrumentation used to record test data, including the SNL data loggingequipment and the UL furnace-monitoring and control systems, was calibratedusing equipment traceable to National Institute of Standards and Technologystandards. NRC, SNL, and UL participated in and observed all four test IN 94-22March 16, 1994 Fire Endurance TestsThe following performance capabilities were evaluated: (1) the ability of theThermo-Lag barrier to keep the average temperature of the unexposed side ofthe barrier (as measured on the exterior surface of the cable trays) fromrising more than 139 *C [250 OF] above the ambient temperature at the start ofthe test, (2) the ability to keep the temperature of any single thermocouplefrom rising more than 30 percent above the allowable average temperature rise(181 'C [325 OF]), (3) the ability to maintain circuit integrity during thefire exposure and hose stream test, (4) the ability to maintain the cablesfree of visible fire damage, and (5) the ability to remain intact during thefire and hose stream tests.Temperatures were measured by Teflon-insulated Type K thermocouples installedon certain cables (as documented in the vendor test reports). In addition,thermocouples were installed on the cable tray side rails, on the unexposedside of the Thermo-Lag panels, and in the air space between the cables and theunexposed side of the Thermo-Lag panels. In keeping with the objective ofevaluating thermal performance against test results previously reported by thevendor, the temperature results reported below were those measured by thethermocouples installed on the cables and the cable tray side rails. Fourcables in each of the fire tests were connected to a separate low-voltagepower supply (28-VDC, 1 Amp) which was configured to conduct circuit-to-circuit (conductor-to-conductor), circuit-to-ground (conductor-to-ground), andcircuit-to-system (conductor continuity) integrity tests as documented in thevendor test reports.The three fire endurance tests were performed in the UL column furnace. Tofacilitate duplication of the original TSI test configurations, UL modifiedthe nominal 10-foot by 10-foot by 10-foot furnace to allow the test to beinserted into the furnace through one of the furnace walls. The standardtime-temperature fire from American Society for Testing of Materials (ASTM)Standard E-119-75, "Standard Methods of Fire Tests of Building Constructionand Materials," was followed. UL technicians operated the test furnace andrecorded the furnace temperature data. SNL provided the instrumentation anddata acquisition system for obtaining and recording the test temperature andcircuit integrity data. During the fire exposure, visual observations weremade through viewing ports located in three of the furnace walls. Thefollowing test results are summarized in Table 2.Article I was tested on December 8, 1993. The ambient temperature at thestart of the test was 19 OC [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperaturerise criterion was 200 *C [392 *F]. The single-point temperature criterionwas exceeded about 1 hour and 5 minutes after the start of the test (1:05). Aconductor-to-ground fault was detected at about 1:16 and the averagetemperature rise criterion was exceeded at about 1:20. The test wasterminated at 2:30.Article 2 was tested on December 7, 1993. The ambient temperature at thestart of the test was 19 'C [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperature | |||
\J V IN 94-22March 16, 1994 rise criterion was 200 *C [392 'FJ. The single-point temperature criterionwas exceeded at about 0:55, a conductor-to-ground fault was detected atabout 0:59, and the average temperature criterion was exceeded at about 1:03.The test was terminated at 2:00.Article 3 was tested on December 6, 1993. The ambient temperature at thestart of the test was 20 OC (68 *F]. Therefore, the average temperature risecriterion for this test was 159 'C [318 'F] and the single-point temperaturerise criterion was 201 *C [394 'FJ. The single-point temperature criterionwas exceeded at about 1:50, the average temperature rise criterion wasexceeded at about 1:58, and a conductor-to-ground fault was detected atabout 1:59. The test was terminated at 3:00.For all three fire tests, when the tests were terminated, most of theindividual thermocouples exceeded the single point temperature criterion. Inaddition, Thermo-Lag panels had fallen off the test articles exposing thecable trays and cables to the fire. Most of the remaining Thermo-Lag had beenreduced to char. Post-test inspections revealed that all of the cable Jacketand conductor insulation had been consumed during the fire exposures. Onlybare copper conductors remained in the cable trays. Detailed test results,including temperature data, observations and photographs will be provided inSNL Report SAND94-0146.The test plan specified that a standard ASTM solid hose stream test would beperformed at the end of the fire test. However, because of the earlytermination of two of the three tests and the poor condition of all threearticles when the tests were terminated, the hose stream tests were notconducted. Less severe hose streams were used, however, to extinguish theburning Thermo-Lag material and to cool the test articles. These hose streamswashed away most of the Thermo-Lag that had not fallen from the articlesduring the fire exposure.Ampacitv Derating TestTest Article 4 was an ampacity derating test article constructed in accordancewith TSI Report 82-5-355F, "Ampacity Derating Test for 1000V Power Cables in atadder Cable Tray Protected with a Three Hour Rated Design of theThermo-Lag 330-1 Subliming Coating Envelope System,' July 13, 1982. The cabletray was loaded to about 60 percent of the full tray depth with 20 lengths of1/C, 2/0 AWG, 600-V cable; 58 lengths of 1/C, 4 AWG, 600-V cable; and 99lengths of 1/C, 8 AWG, 600-V cable. One length represented one pass throughthe cable tray. All of the cables of a given cable size were Joined togetherinto a single electrical loop. Each loop was instrumented with six 24-gaugebare-bead Type K thermocouples with welded Junctions. In each case, theinsulation on the cable was slit so that the thermocouple Junction could beinstalled below the insulation in contact with the conductor. Thermocoupleswere also installed on the cable tray side rails, on the inner surface of thefire barrier, and on the outer surface of the fire barrier. Threethermocouples were installed to measure the ambient temperature in the testchamber discussed belo IN 94-22March 16, 1994 Cable ampacity and temperature data was obtained for Test Article 4 before theThermo-Lag fire barrier was installed (baseline or unprotected cable traydata). On October 14, 1993, Article 4 was placed in a high-ambienttemperature environmental test chamber set at 40 DC [104 OF] and allowed tosoak for about four hours. A separate power supply was connected to each ofthe three cable loops and power was applied according to an initial estimateof the ampacity of each cable. The amperage was adjusted over a period ofabout six hours until it appeared that a steady state conductor temperaturenear 90 *C [194 *F] at the hot spot for each cable size would be reached. Thetest article was left to settle overnight (about 16 hours). The next day,final ampacity adjustments were made, and the test article was again allowedto settle (typically two to three hours after each adjustment). Stableconditions were achieved after the final adjustments when the cabletemperatures did not fluctuate more than +/-1 OC [1.8 *F] between repeated10-minute interval data scans. After stable conditions were reached, thebaseline temperatures were logged at 10-minute intervals for a final 1-hourperiod. Cable amperage readings were also taken at the beginning and end ofthe final hour to verify the presence of stable source currents. Followingthe baseline test, the 3-hour Thermo-Lag fire barrier described above wasinstalled on Article 4 and allowed to cure. On December 9 and 10, 1993, theprotected cable tray ampacity and temperature data were obtained in accordancewith the process used to obtain the baseline data.Baseline and protected cable ampacity adjustment factors (AF) were calculatedfor each cable size according to the following formula from Insulated CableEngineers Association (ICEA) Standard P-46-426, "Power Cable Ampacities:"=r I, (AF,) W IC TcI 245~~0 T 234.5 + T14c c c ¢ 4(Tc -T, a 234.5 + Vc)where the values with primes indicate the desired conditions and the valueswithout primes indicate the experimental data. Temperature units are degreesCelsius. For both the baseline and the protected cases, the desired cabletemperature (T' ) was 90 *C [194 OF] and the desired ambient temperature (T' )was 40 'C [104 IF]. The measured baseline temperatures and ampacities and thecalculated baseline ampacity adjustment factors are provided in Table 3. Themeasured temperatures and ampacities and the calculated ampacity adjustmentfactors for the protected cables are provided in Table 4. For both thebaseline and protected cases, the average of the hot-spot cable temperaturesrecorded at 10-minute intervals during the final hour were used to calculatethe ampacity adjustment factor for that cable.The ampacity derating factor (ADF) for each cable type is the ratio of thereduction in current carrying capacity (protected ampacities) to the original | <<J IN 94-22March 16, 1994 DiscussionEach of the four base test articles was a U-shaped configuration layingsideways which duplicated configurations, material specifications, dimensions,orientations, cable types and fills, and instrumentation, previously testedand reported by the vendor. A single layer of cables was installed in each ofthe fire test articles in accordance with the types and placements reported inthe vendor's test reports. The cable fill for the ampacity derating testarticle is discussed under the "Ampacity Derating Test" section of thisinformation notice.Each of the base test articles was protected by a 3-hour fire barrier formedfrom two layers of nominal 3/4-inch-thick Thermo-Lag 330-1 preformed panel. SNLpurchased the Thermo-Lag preformed panels and trowel-grade material used toconstruct the test article fire barriers from Texas Utilities Electric Company(TU Electric). TU Electric performed a source inspection of the materials atTSI and the NRR Vendor Inspection Branch conducted a receipt inspection of thematerials at the Comanche Peak Steam Electric Station when TU Electricdelivered the materials to SNL.The fire barriers for Test Articles 1, 2, and 4, were constructed inaccordance with TSI Technical Note 20684, Revision V, "Thermo-Lag 330 FireBarrier System Installation Procedures Manual Power Generating PlantApplication," November 1985. The fire barrier for Test Article 3 wasconstructed in accordance with the methods used by the vendor for TestArticle 4 of TSI Report 82-11-81, "Three Hour Fire Endurance Tests Conductedon Test Articles Containing Generic Cables Protected with the Thermo-Lag 330-1Subliming Coating Envelope System," November 1982. Table I summarizes thetest article characteristics.The stress skin (an embedded wire mesh) for the inner barrier layer facedtoward the cable tray. The stress skin for the outer layer faced away fromthe cable tray. All joints and seams were offset. The edges of theindividual panel sections were buttered with trowel-grade Thermo-Lag 330-1material before they were joined and secured. This assembly technique, asopposed to the dry-fit method, ensured that each Joint and seam was filled toits full thickness with Thermo-Lag material. The individual barrier piecesfor Test Articles 1, 2, and 4 were banded with stainless steel tie wire. Theindividual pieces for Test Article 3 were not banded. Instead, each seam andjoint was reinforced with stainless steel wire stitches and laces. Inaddition, flanges were formed along the edges and butt Joints of the outerlayer. The flanges were bolted together with nominal k-inch-20 by 2-inchmachine bolts and hex-nuts. After the barriers were installed, the testarticles were cured for at least 30 days in a secure temperature-controlledenvironment before the tests were conducted.The instrumentation used to record test data, including the SNL data loggingequipment and the UL furnace-monitoring and control systems, was calibratedusing equipment traceable to National Institute of Standards and Technologystandards. NRC, SNL, and UL participated in and observed all four test IN 94-22March 16, 1994 Fire Endurance TestsThe following performance capabilities were evaluated: (1) the ability of theThermo-Lag barrier to keep the average temperature of the unexposed side ofthe barrier (as measured on the exterior surface of the cable trays) fromrising more than 139 *C [250 OF] above the ambient temperature at the start ofthe test, (2) the ability to keep the temperature of any single thermocouplefrom rising more than 30 percent above the allowable average temperature rise(181 'C [325 OF]), (3) the ability to maintain circuit integrity during thefire exposure and hose stream test, (4) the ability to maintain the cablesfree of visible fire damage, and (5) the ability to remain intact during thefire and hose stream tests.Temperatures were measured by Teflon-insulated Type K thermocouples installedon certain cables (as documented in the vendor test reports). In addition,thermocouples were installed on the cable tray side rails, on the unexposedside of the Thermo-Lag panels, and in the air space between the cables and theunexposed side of the Thermo-Lag panels. In keeping with the objective ofevaluating thermal performance against test results previously reported by thevendor, the temperature results reported below were those measured by thethermocouples installed on the cables and the cable tray side rails. Fourcables in each of the fire tests were connected to a separate low-voltagepower supply (28-VDC, 1 Amp) which was configured to conduct circuit-to-circuit (conductor-to-conductor), circuit-to-ground (conductor-to-ground), andcircuit-to-system (conductor continuity) integrity tests as documented in thevendor test reports.The three fire endurance tests were performed in the UL column furnace. Tofacilitate duplication of the original TSI test configurations, UL modifiedthe nominal 10-foot by 10-foot by 10-foot furnace to allow the test to beinserted into the furnace through one of the furnace walls. The standardtime-temperature fire from American Society for Testing of Materials (ASTM)Standard E-119-75, "Standard Methods of Fire Tests of Building Constructionand Materials," was followed. UL technicians operated the test furnace andrecorded the furnace temperature data. SNL provided the instrumentation anddata acquisition system for obtaining and recording the test temperature andcircuit integrity data. During the fire exposure, visual observations weremade through viewing ports located in three of the furnace walls. Thefollowing test results are summarized in Table 2.Article I was tested on December 8, 1993. The ambient temperature at thestart of the test was 19 OC [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperaturerise criterion was 200 *C [392 *F]. The single-point temperature criterionwas exceeded about 1 hour and 5 minutes after the start of the test (1:05). Aconductor-to-ground fault was detected at about 1:16 and the averagetemperature rise criterion was exceeded at about 1:20. The test wasterminated at 2:30.Article 2 was tested on December 7, 1993. The ambient temperature at thestart of the test was 19 'C [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperature | ||
\J V IN 94-22March 16, 1994 rise criterion was 200 *C [392 'FJ. The single-point temperature criterionwas exceeded at about 0:55, a conductor-to-ground fault was detected atabout 0:59, and the average temperature criterion was exceeded at about 1:03.The test was terminated at 2:00.Article 3 was tested on December 6, 1993. The ambient temperature at thestart of the test was 20 OC (68 *F]. Therefore, the average temperature risecriterion for this test was 159 'C [318 'F] and the single-point temperaturerise criterion was 201 *C [394 'FJ. The single-point temperature criterionwas exceeded at about 1:50, the average temperature rise criterion wasexceeded at about 1:58, and a conductor-to-ground fault was detected atabout 1:59. The test was terminated at 3:00.For all three fire tests, when the tests were terminated, most of theindividual thermocouples exceeded the single point temperature criterion. Inaddition, Thermo-Lag panels had fallen off the test articles exposing thecable trays and cables to the fire. Most of the remaining Thermo-Lag had beenreduced to char. Post-test inspections revealed that all of the cable Jacketand conductor insulation had been consumed during the fire exposures. Onlybare copper conductors remained in the cable trays. Detailed test results,including temperature data, observations and photographs will be provided inSNL Report SAND94-0146.The test plan specified that a standard ASTM solid hose stream test would beperformed at the end of the fire test. However, because of the earlytermination of two of the three tests and the poor condition of all threearticles when the tests were terminated, the hose stream tests were notconducted. Less severe hose streams were used, however, to extinguish theburning Thermo-Lag material and to cool the test articles. These hose streamswashed away most of the Thermo-Lag that had not fallen from the articlesduring the fire exposure.Ampacitv Derating TestTest Article 4 was an ampacity derating test article constructed in accordancewith TSI Report 82-5-355F, "Ampacity Derating Test for 1000V Power Cables in atadder Cable Tray Protected with a Three Hour Rated Design of theThermo-Lag 330-1 Subliming Coating Envelope System,' July 13, 1982. The cabletray was loaded to about 60 percent of the full tray depth with 20 lengths of1/C, 2/0 AWG, 600-V cable; 58 lengths of 1/C, 4 AWG, 600-V cable; and 99lengths of 1/C, 8 AWG, 600-V cable. One length represented one pass throughthe cable tray. All of the cables of a given cable size were Joined togetherinto a single electrical loop. Each loop was instrumented with six 24-gaugebare-bead Type K thermocouples with welded Junctions. In each case, theinsulation on the cable was slit so that the thermocouple Junction could beinstalled below the insulation in contact with the conductor. Thermocoupleswere also installed on the cable tray side rails, on the inner surface of thefire barrier, and on the outer surface of the fire barrier. Threethermocouples were installed to measure the ambient temperature in the testchamber discussed belo IN 94-22March 16, 1994 Cable ampacity and temperature data was obtained for Test Article 4 before theThermo-Lag fire barrier was installed (baseline or unprotected cable traydata). On October 14, 1993, Article 4 was placed in a high-ambienttemperature environmental test chamber set at 40 DC [104 OF] and allowed tosoak for about four hours. A separate power supply was connected to each ofthe three cable loops and power was applied according to an initial estimateof the ampacity of each cable. The amperage was adjusted over a period ofabout six hours until it appeared that a steady state conductor temperaturenear 90 *C [194 *F] at the hot spot for each cable size would be reached. Thetest article was left to settle overnight (about 16 hours). The next day,final ampacity adjustments were made, and the test article was again allowedto settle (typically two to three hours after each adjustment). Stableconditions were achieved after the final adjustments when the cabletemperatures did not fluctuate more than +/-1 OC [1.8 *F] between repeated10-minute interval data scans. After stable conditions were reached, thebaseline temperatures were logged at 10-minute intervals for a final 1-hourperiod. Cable amperage readings were also taken at the beginning and end ofthe final hour to verify the presence of stable source currents. Followingthe baseline test, the 3-hour Thermo-Lag fire barrier described above wasinstalled on Article 4 and allowed to cure. On December 9 and 10, 1993, theprotected cable tray ampacity and temperature data were obtained in accordancewith the process used to obtain the baseline data.Baseline and protected cable ampacity adjustment factors (AF) were calculatedfor each cable size according to the following formula from Insulated CableEngineers Association (ICEA) Standard P-46-426, "Power Cable Ampacities:"=r I, (AF,) W IC TcI 245~~0 T 234.5 + T14c c c ¢ 4(Tc -T, a 234.5 + Vc)where the values with primes indicate the desired conditions and the valueswithout primes indicate the experimental data. Temperature units are degreesCelsius. For both the baseline and the protected cases, the desired cabletemperature (T' ) was 90 *C [194 OF] and the desired ambient temperature (T' )was 40 'C [104 IF]. The measured baseline temperatures and ampacities and thecalculated baseline ampacity adjustment factors are provided in Table 3. Themeasured temperatures and ampacities and the calculated ampacity adjustmentfactors for the protected cables are provided in Table 4. For both thebaseline and protected cases, the average of the hot-spot cable temperaturesrecorded at 10-minute intervals during the final hour were used to calculatethe ampacity adjustment factor for that cable.The ampacity derating factor (ADF) for each cable type is the ratio of thereduction in current carrying capacity (protected ampacities) to the original | |||
;. '_.<J IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula:ADF Ibaslne jIProtected (100)IbasollneIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in TSI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-sted recalculations, whichwere needed to allow comparisons of the SNL/UL test resulte with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR(301) 504-1220 | ;. '_.<J IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula:ADF Ibaslne jIProtected (100)IbasollneIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in TSI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-sted recalculations, whichwere needed to allow comparisons of the SNL/UL test resulte with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR(301) 504-1220 | ||
===Attachments:=== | ===Attachments:=== | ||
1. Table 1, 'Summary of Test ArticleCharacteristics," and Table 2, "Summaryof Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,'and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications ConcerningFire Barriers5. List of Recently Issued NRC Information Notices | 1. Table 1, 'Summary of Test ArticleCharacteristics," and Table 2, "Summaryof Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,'and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications ConcerningFire Barriers5. List of Recently Issued NRC Information Notices | ||
;ytachment IIN94-22March 16, 1994 Table 1. Summary of Test Article CharacteristicsArticle Tetjye I Description Barrier Design1 3-Hour 6-inch-wide by 6-inch-high, Based on TSIFire solid-bottom, steel cable tray TechnicalEndurance based on Test Article 2 of TSI Note 20684,Report 82-5-355B, "Three-Hour Revision V,Fire Endurance Test on November 1985.Thermo-Lag 330-1 SublimingCoating Envelope System forWashington Public Power SupplySystem-Nuclear Projects,'l _____ _ .July 1982. ,_l2 3-Hour 12-inch-wide by 4-inch-high, Same as Article 1.Fire ladder-back, steel cable trayEndurance based on Test Article 4 of TSIReport 82-11-81, November 1982.3 3-Hour Same as Test Article 2. Methods documentedFire in TSI ReportEndurance 82-11-81,November 1982.4 Ampacity 12-inch-wide by 4-inch-high, Same as TestDerating ladder-back, steel cable tray Article 1.based on TSI Report 82-5-355F,lI July 13, 1982.Table 2. Summary of Fire Endurance Test Results(All times in Hours:Minutes from the start of the test)Article Single Point .Average Time to TestTemperature Temperature Circuit DurationCriterion and Time Criterion and Time Faultto Exceed to Exceed1 200 -C [392 F] 158 *C [316 -F]1:05 1:20 1:16 2:302 200 *C [392 *F] 158 *C [316 *F]0:55 1:03 0:59 2:003 201 oC [394 OF] 159 C [318 *F ll 1:50 1:58 1:59 3:00 | ;ytachment IIN94-22March 16, 1994 Table 1. Summary of Test Article CharacteristicsArticle Tetjye I Description Barrier Design1 3-Hour 6-inch-wide by 6-inch-high, Based on TSIFire solid-bottom, steel cable tray TechnicalEndurance based on Test Article 2 of TSI Note 20684,Report 82-5-355B, "Three-Hour Revision V,Fire Endurance Test on November 1985.Thermo-Lag 330-1 SublimingCoating Envelope System forWashington Public Power SupplySystem-Nuclear Projects,'l _____ _ .July 1982. ,_l2 3-Hour 12-inch-wide by 4-inch-high, Same as Article 1.Fire ladder-back, steel cable trayEndurance based on Test Article 4 of TSIReport 82-11-81, November 1982.3 3-Hour Same as Test Article 2. Methods documentedFire in TSI ReportEndurance 82-11-81,November 1982.4 Ampacity 12-inch-wide by 4-inch-high, Same as TestDerating ladder-back, steel cable tray Article 1.based on TSI Report 82-5-355F,lI July 13, 1982.Table 2. Summary of Fire Endurance Test Results(All times in Hours:Minutes from the start of the test)Article Single Point .Average Time to TestTemperature Temperature Circuit DurationCriterion and Time Criterion and Time Faultto Exceed to Exceed1 200 -C [392 F] 158 *C [316 -F]1:05 1:20 1:16 2:302 200 *C [392 *F] 158 *C [316 *F]0:55 1:03 0:59 2:003 201 oC [394 OF] 159 C [318 *F ll 1:50 1:58 1:59 3:00 | ||
\-- itachment 2IN 94-22March 16, 1994 Table 3. Baseline (Unprotected Cable Tray)Ampacity Test Data and CalculationsCable Tc (0C) Ta (C) lI (Amps) AFc Ic (Amps)Size I8 AWG 91.1 io.5 23.8 0.996 23.74 AWG 91.2 40.5 38.0 0.995 37.82/0 92.0 40.5 115.0 0.988 113.6Table 4. Protected Cable TrayAmpacity Test Data and CalculationsCable Tc l-C) l Ta (C) j Ic (Amps) j AFC I'c (Amps)8 AWG 92.9 40.1 l 13.0 0.977 12.74 AWG 93.2 40.1 24.8 0.975 24.22/0 91.6 40.1 I 74.4 1 0.988 73.5Key for Tables 3 and 4:TC = Average of cable temperatures recorded at 10-minuteintervals during the final hour.To = Average of ambient (test chamber) temperaturesrecorded at 10-minute Intervals during the finalhour after reaching desired stable conditions.IC a Measured cable ampacity at the end of thefinal hour.AFC = Cable ampacity adjustment factor.I'C a Adjusted cable ampacit I tachment 3IN 94-22March 16, 1994 Table S. Comparative Summary of Ampacity Data and Derating FactorsCable Size Data Source Baseline Protected DeratingAmpacity Ampacity Factor(Amps) (Amps) (Percent)8 AWG SNL 23.7 12.7 46.4TSI1 17.46 14.64 16.15TSI2 20.38 13.89 31.84TS13 23.96 14.83 38.114 AWG SNL 37.8 24.2 36.0TSI1 35.77 29.74 16.86TS12 41.75 28.21 32.43TSI3 41.75 28.21 32.432/0 SNL 113.6 73.5 35.3TSP1 105.91 87.18 17.68TSI2 123.60 82.69 33.10TSI3 131.60 84.82 35.551 Data reported in TSI Report 82-5-355F, July 13, 1982.2 Inverted term in ampacity adjustment factor (AF) equation corrected.3 Measured individual conductor temperatures used to calculate ampacityadjustment factors for each cable siz _.>2tachment 4IN 94-22March 16, 1994 List of Generic Communications Concerning Fire BarriersInformation Notice 91-47, 'Failure of Thermo-Lag Fire Barrier Materialto Pass Fire Endurance Test," August 6, 1991Information Notice 91-79, "Deficiencies in the Procedures forInstalling Thermo-Lag Fire Barrier Materials," December 6, 1991Information Notice 92-46, 'Thermo-Lag Fire Barrier Material SpecialReview Team Final Report Findings, Current Fire Endurance Tests, andAmpacity Calculation Errors," June 23, 1992Bulletin 92-01, "Failure of Thermo-Lag 330 Fire Barrier System toMaintain Cabling in Wide Cable Trays and Small Conduits Free from FireDamage," June 24, 1992Information Notice 92-55, "Current Fire Endurance Test Results forThermo-Lag Fire Barrier Material," July 27, 1992Bulletin 92-01 Supplement 1, "Failure of Thermo-Lag 330 Fire BarrierSystem to Perform Its Specified Fire Endurance Function,"August 28, 1992Information Notice 92-82, "Results of Thermo-Lag 330-1 CombustibilityTesting," December 15, 1992Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers,"December 17, 1992Information Notice 93-40, "Fire Endurance Test Results for ThermalCeramics FP-60 Fire Barrier Material," May 26, 1993Information Notice 93-41, "One Hour Fire Endurance Test Results forThermal Ceramics Kaowool, 3M Company FS-195 and 3M CompanyInteram E-50 Fire Barrier Systems," May 28, 1993 A 9chment 5Io-4-22March 16, 1994 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to94-2194-2094-19Regulatory Requirementswhen No Operations arebeing PerformedCommon-Cause Failuresdue to InadequateDesign Control andDedicationEmergency DieselGenerator Vulnerabilityto Failure from ColdFuel OilAccuracy of Motor-Operated Valve Diag-nostic Equipment(Responses to Sup-plement 5 to GenericLetter 89-10)Strontium-90 Eye Appli-cators: Submission ofQuality Management Plan(QMP), Calibration, andUseRecent Incidents Resultingin Offsite ContaminationRadiation Exposures duringan Event Involving a FixedNuclear Gauge03/18/9403/17/9403/16/9403/16/9403/11/9403/03/9403/02/94All fuel cycle and materialslicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All U.S. Nuclear RegulatoryCommission Medical UseLicensees.All U.S. Nuclear RegulatoryCommission material and fuelcycle licensees.All U.S. Nuclear RegulatoryCommission licensees author-ized to possess, use, manu-facture, or distributeindustrial nuclear gauges.94-1794-1694-15OL -Operating LicenseCP = Construction Permit IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula:ADF = baseline -protected (100)baselineIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in BI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-step recalculations, whichwere needed to allow comparisons of the SNL/UL test results with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager. diginslignedbyBrian K. Grimes, Director dan K. GrimesDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR, (301) 504-1220 | \-- itachment 2IN 94-22March 16, 1994 Table 3. Baseline (Unprotected Cable Tray)Ampacity Test Data and CalculationsCable Tc (0C) Ta (C) lI (Amps) AFc Ic (Amps)Size I8 AWG 91.1 io.5 23.8 0.996 23.74 AWG 91.2 40.5 38.0 0.995 37.82/0 92.0 40.5 115.0 0.988 113.6Table 4. Protected Cable TrayAmpacity Test Data and CalculationsCable Tc l-C) l Ta (C) j Ic (Amps) j AFC I'c (Amps)8 AWG 92.9 40.1 l 13.0 0.977 12.74 AWG 93.2 40.1 24.8 0.975 24.22/0 91.6 40.1 I 74.4 1 0.988 73.5Key for Tables 3 and 4:TC = Average of cable temperatures recorded at 10-minuteintervals during the final hour.To = Average of ambient (test chamber) temperaturesrecorded at 10-minute Intervals during the finalhour after reaching desired stable conditions.IC a Measured cable ampacity at the end of thefinal hour.AFC = Cable ampacity adjustment factor.I'C a Adjusted cable ampacit I tachment 3IN 94-22March 16, 1994 Table S. Comparative Summary of Ampacity Data and Derating FactorsCable Size Data Source Baseline Protected DeratingAmpacity Ampacity Factor(Amps) (Amps) (Percent)8 AWG SNL 23.7 12.7 46.4TSI1 17.46 14.64 16.15TSI2 20.38 13.89 31.84TS13 23.96 14.83 38.114 AWG SNL 37.8 24.2 36.0TSI1 35.77 29.74 16.86TS12 41.75 28.21 32.43TSI3 41.75 28.21 32.432/0 SNL 113.6 73.5 35.3TSP1 105.91 87.18 17.68TSI2 123.60 82.69 33.10TSI3 131.60 84.82 35.551 Data reported in TSI Report 82-5-355F, July 13, 1982.2 Inverted term in ampacity adjustment factor (AF) equation corrected.3 Measured individual conductor temperatures used to calculate ampacityadjustment factors for each cable siz _.>2tachment 4IN 94-22March 16, 1994 List of Generic Communications Concerning Fire BarriersInformation Notice 91-47, 'Failure of Thermo-Lag Fire Barrier Materialto Pass Fire Endurance Test," August 6, 1991Information Notice 91-79, "Deficiencies in the Procedures forInstalling Thermo-Lag Fire Barrier Materials," December 6, 1991Information Notice 92-46, 'Thermo-Lag Fire Barrier Material SpecialReview Team Final Report Findings, Current Fire Endurance Tests, andAmpacity Calculation Errors," June 23, 1992Bulletin 92-01, "Failure of Thermo-Lag 330 Fire Barrier System toMaintain Cabling in Wide Cable Trays and Small Conduits Free from FireDamage," June 24, 1992Information Notice 92-55, "Current Fire Endurance Test Results forThermo-Lag Fire Barrier Material," July 27, 1992Bulletin 92-01 Supplement 1, "Failure of Thermo-Lag 330 Fire BarrierSystem to Perform Its Specified Fire Endurance Function,"August 28, 1992Information Notice 92-82, "Results of Thermo-Lag 330-1 CombustibilityTesting," December 15, 1992Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers,"December 17, 1992Information Notice 93-40, "Fire Endurance Test Results for ThermalCeramics FP-60 Fire Barrier Material," May 26, 1993Information Notice 93-41, "One Hour Fire Endurance Test Results forThermal Ceramics Kaowool, 3M Company FS-195 and 3M CompanyInteram E-50 Fire Barrier Systems," May 28, 1993 A 9chment 5Io-4-22March 16, 1994 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to94-2194-2094-19Regulatory Requirementswhen No Operations arebeing PerformedCommon-Cause Failuresdue to InadequateDesign Control andDedicationEmergency DieselGenerator Vulnerabilityto Failure from ColdFuel OilAccuracy of Motor-Operated Valve Diag-nostic Equipment(Responses to Sup-plement 5 to GenericLetter 89-10)Strontium-90 Eye Appli-cators: Submission ofQuality Management Plan(QMP), Calibration, andUseRecent Incidents Resultingin Offsite ContaminationRadiation Exposures duringan Event Involving a FixedNuclear Gauge03/18/9403/17/9403/16/9403/16/9403/11/9403/03/9403/02/94All fuel cycle and materialslicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All U.S. Nuclear RegulatoryCommission Medical UseLicensees.All U.S. Nuclear RegulatoryCommission material and fuelcycle licensees.All U.S. Nuclear RegulatoryCommission licensees author-ized to possess, use, manu-facture, or distributeindustrial nuclear gauges.94-1794-1694-15OL -Operating LicenseCP = Construction Permit IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula:ADF = baseline -protected (100)baselineIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in BI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-step recalculations, whichwere needed to allow comparisons of the SNL/UL test results with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager. diginslignedbyBrian K. Grimes, Director dan K. GrimesDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR, (301) 504-1220 |
Revision as of 16:06, 4 March 2018
UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555March 16, 1994NRC INFORMATION NOTICE 94-22: FIRE ENDURANCE AND AMPACITY DERATING TESTRESULTS FOR 3-HOUR FIRE-RATED THERMO-LAG 330-1FIRE BARRIERS
Addressees
All holders of operating licenses or construction permits for nuclear powerreactors.
Purpose
6The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to inform licensees of the preliminary results of fire endurance andampacity derating tests of Thermo-Lag 330-1 (Thermo-Lag) fire barriersconducted by the NRC at Underwriters Laboratories, Incorporated (UL). It isexpected that recipients will review the Information for applicability totheir facilities and consider actions as appropriate to avoid similarproblems. However, suggestions contained in this information notice are notNRC requirements; therefore, no specific action or written response isrequired.
Description of Circumstances
As part of its continuing evaluation of Thermo-Lag fire barrier performance,the NRC Office of Nuclear Reactor Regulation (NRR) conducted three full-scalefire endurance tests and one full-scale ampacity derating test of 3-hourfire-rated Thermo-Lag fire barriers. The principal objective of the tests wasto evaluate the performance of the barriers against the results of testspreviously reported by Thermal Science, Incorporated (TSI, the vendor).Sandia National Laboratories (SNL), Albuquerque, New Mexico, providedtechnical assistance by designing and executing the test program and preparingthe test report. The base test specimens were constructed and instrumented atSNL. The test specimen fire barriers were constructed at UL by trainedThermo-Lag installers under the direction of SNL during October andNovember 1993. The tests were conducted at UL under the direction of the NRCand SNL during December 1993. The NRC staff informed the Nuclear Managementand Resources Council (NUMARC) of the test results during a public meeting atNRC Headquarters on February 9, 1994. The final test results will bedocumented in SNL Report SAND94-0146, "An Evaluation of the Fire BarrierSystem Thermo-Lag 330-1." The staff will place this report in the NRC PublicDocument Room after it is completed. The staff expects the report to becompleted during April 1994._Efh-1X-9403150511 ,r.D9af aqedqij4- o,2~.3/2! 5/Y9q 0 3 1 (Il
<<J IN 94-22March 16, 1994 DiscussionEach of the four base test articles was a U-shaped configuration layingsideways which duplicated configurations, material specifications, dimensions,orientations, cable types and fills, and instrumentation, previously testedand reported by the vendor. A single layer of cables was installed in each ofthe fire test articles in accordance with the types and placements reported inthe vendor's test reports. The cable fill for the ampacity derating testarticle is discussed under the "Ampacity Derating Test" section of thisinformation notice.Each of the base test articles was protected by a 3-hour fire barrier formedfrom two layers of nominal 3/4-inch-thick Thermo-Lag 330-1 preformed panel. SNLpurchased the Thermo-Lag preformed panels and trowel-grade material used toconstruct the test article fire barriers from Texas Utilities Electric Company(TU Electric). TU Electric performed a source inspection of the materials atTSI and the NRR Vendor Inspection Branch conducted a receipt inspection of thematerials at the Comanche Peak Steam Electric Station when TU Electricdelivered the materials to SNL.The fire barriers for Test Articles 1, 2, and 4, were constructed inaccordance with TSI Technical Note 20684, Revision V, "Thermo-Lag 330 FireBarrier System Installation Procedures Manual Power Generating PlantApplication," November 1985. The fire barrier for Test Article 3 wasconstructed in accordance with the methods used by the vendor for TestArticle 4 of TSI Report 82-11-81, "Three Hour Fire Endurance Tests Conductedon Test Articles Containing Generic Cables Protected with the Thermo-Lag 330-1Subliming Coating Envelope System," November 1982. Table I summarizes thetest article characteristics.The stress skin (an embedded wire mesh) for the inner barrier layer facedtoward the cable tray. The stress skin for the outer layer faced away fromthe cable tray. All joints and seams were offset. The edges of theindividual panel sections were buttered with trowel-grade Thermo-Lag 330-1material before they were joined and secured. This assembly technique, asopposed to the dry-fit method, ensured that each Joint and seam was filled toits full thickness with Thermo-Lag material. The individual barrier piecesfor Test Articles 1, 2, and 4 were banded with stainless steel tie wire. Theindividual pieces for Test Article 3 were not banded. Instead, each seam andjoint was reinforced with stainless steel wire stitches and laces. Inaddition, flanges were formed along the edges and butt Joints of the outerlayer. The flanges were bolted together with nominal k-inch-20 by 2-inchmachine bolts and hex-nuts. After the barriers were installed, the testarticles were cured for at least 30 days in a secure temperature-controlledenvironment before the tests were conducted.The instrumentation used to record test data, including the SNL data loggingequipment and the UL furnace-monitoring and control systems, was calibratedusing equipment traceable to National Institute of Standards and Technologystandards. NRC, SNL, and UL participated in and observed all four test IN 94-22March 16, 1994 Fire Endurance TestsThe following performance capabilities were evaluated: (1) the ability of theThermo-Lag barrier to keep the average temperature of the unexposed side ofthe barrier (as measured on the exterior surface of the cable trays) fromrising more than 139 *C [250 OF] above the ambient temperature at the start ofthe test, (2) the ability to keep the temperature of any single thermocouplefrom rising more than 30 percent above the allowable average temperature rise(181 'C [325 OF]), (3) the ability to maintain circuit integrity during thefire exposure and hose stream test, (4) the ability to maintain the cablesfree of visible fire damage, and (5) the ability to remain intact during thefire and hose stream tests.Temperatures were measured by Teflon-insulated Type K thermocouples installedon certain cables (as documented in the vendor test reports). In addition,thermocouples were installed on the cable tray side rails, on the unexposedside of the Thermo-Lag panels, and in the air space between the cables and theunexposed side of the Thermo-Lag panels. In keeping with the objective ofevaluating thermal performance against test results previously reported by thevendor, the temperature results reported below were those measured by thethermocouples installed on the cables and the cable tray side rails. Fourcables in each of the fire tests were connected to a separate low-voltagepower supply (28-VDC, 1 Amp) which was configured to conduct circuit-to-circuit (conductor-to-conductor), circuit-to-ground (conductor-to-ground), andcircuit-to-system (conductor continuity) integrity tests as documented in thevendor test reports.The three fire endurance tests were performed in the UL column furnace. Tofacilitate duplication of the original TSI test configurations, UL modifiedthe nominal 10-foot by 10-foot by 10-foot furnace to allow the test to beinserted into the furnace through one of the furnace walls. The standardtime-temperature fire from American Society for Testing of Materials (ASTM)Standard E-119-75, "Standard Methods of Fire Tests of Building Constructionand Materials," was followed. UL technicians operated the test furnace andrecorded the furnace temperature data. SNL provided the instrumentation anddata acquisition system for obtaining and recording the test temperature andcircuit integrity data. During the fire exposure, visual observations weremade through viewing ports located in three of the furnace walls. Thefollowing test results are summarized in Table 2.Article I was tested on December 8, 1993. The ambient temperature at thestart of the test was 19 OC [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperaturerise criterion was 200 *C [392 *F]. The single-point temperature criterionwas exceeded about 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and 5 minutes after the start of the test (1:05). Aconductor-to-ground fault was detected at about 1:16 and the averagetemperature rise criterion was exceeded at about 1:20. The test wasterminated at 2:30.Article 2 was tested on December 7, 1993. The ambient temperature at thestart of the test was 19 'C [66 OF]. Therefore, the average temperature risecriterion for this test was 158 *C [316 OF] and the single-point temperature
\J V IN 94-22March 16, 1994 rise criterion was 200 *C [392 'FJ. The single-point temperature criterionwas exceeded at about 0:55, a conductor-to-ground fault was detected atabout 0:59, and the average temperature criterion was exceeded at about 1:03.The test was terminated at 2:00.Article 3 was tested on December 6, 1993. The ambient temperature at thestart of the test was 20 OC (68 *F]. Therefore, the average temperature risecriterion for this test was 159 'C [318 'F] and the single-point temperaturerise criterion was 201 *C [394 'FJ. The single-point temperature criterionwas exceeded at about 1:50, the average temperature rise criterion wasexceeded at about 1:58, and a conductor-to-ground fault was detected atabout 1:59. The test was terminated at 3:00.For all three fire tests, when the tests were terminated, most of theindividual thermocouples exceeded the single point temperature criterion. Inaddition, Thermo-Lag panels had fallen off the test articles exposing thecable trays and cables to the fire. Most of the remaining Thermo-Lag had beenreduced to char. Post-test inspections revealed that all of the cable Jacketand conductor insulation had been consumed during the fire exposures. Onlybare copper conductors remained in the cable trays. Detailed test results,including temperature data, observations and photographs will be provided inSNL Report SAND94-0146.The test plan specified that a standard ASTM solid hose stream test would beperformed at the end of the fire test. However, because of the earlytermination of two of the three tests and the poor condition of all threearticles when the tests were terminated, the hose stream tests were notconducted. Less severe hose streams were used, however, to extinguish theburning Thermo-Lag material and to cool the test articles. These hose streamswashed away most of the Thermo-Lag that had not fallen from the articlesduring the fire exposure.Ampacitv Derating TestTest Article 4 was an ampacity derating test article constructed in accordancewith TSI Report 82-5-355F, "Ampacity Derating Test for 1000V Power Cables in atadder Cable Tray Protected with a Three Hour Rated Design of theThermo-Lag 330-1 Subliming Coating Envelope System,' July 13, 1982. The cabletray was loaded to about 60 percent of the full tray depth with 20 lengths of1/C, 2/0 AWG, 600-V cable; 58 lengths of 1/C, 4 AWG, 600-V cable; and 99lengths of 1/C, 8 AWG, 600-V cable. One length represented one pass throughthe cable tray. All of the cables of a given cable size were Joined togetherinto a single electrical loop. Each loop was instrumented with six 24-gaugebare-bead Type K thermocouples with welded Junctions. In each case, theinsulation on the cable was slit so that the thermocouple Junction could beinstalled below the insulation in contact with the conductor. Thermocoupleswere also installed on the cable tray side rails, on the inner surface of thefire barrier, and on the outer surface of the fire barrier. Threethermocouples were installed to measure the ambient temperature in the testchamber discussed belo IN 94-22March 16, 1994 Cable ampacity and temperature data was obtained for Test Article 4 before theThermo-Lag fire barrier was installed (baseline or unprotected cable traydata). On October 14, 1993, Article 4 was placed in a high-ambienttemperature environmental test chamber set at 40 DC [104 OF] and allowed tosoak for about four hours. A separate power supply was connected to each ofthe three cable loops and power was applied according to an initial estimateof the ampacity of each cable. The amperage was adjusted over a period ofabout six hours until it appeared that a steady state conductor temperaturenear 90 *C [194 *F] at the hot spot for each cable size would be reached. Thetest article was left to settle overnight (about 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />). The next day,final ampacity adjustments were made, and the test article was again allowedto settle (typically two to three hours after each adjustment). Stableconditions were achieved after the final adjustments when the cabletemperatures did not fluctuate more than +/-1 OC [1.8 *F] between repeated10-minute interval data scans. After stable conditions were reached, thebaseline temperatures were logged at 10-minute intervals for a final 1-hourperiod. Cable amperage readings were also taken at the beginning and end ofthe final hour to verify the presence of stable source currents. Followingthe baseline test, the 3-hour Thermo-Lag fire barrier described above wasinstalled on Article 4 and allowed to cure. On December 9 and 10, 1993, theprotected cable tray ampacity and temperature data were obtained in accordancewith the process used to obtain the baseline data.Baseline and protected cable ampacity adjustment factors (AF) were calculatedfor each cable size according to the following formula from Insulated CableEngineers Association (ICEA) Standard P-46-426, "Power Cable Ampacities:"=r I, (AF,) W IC TcI 245~~0 T 234.5 + T14c c c ¢ 4(Tc -T, a 234.5 + Vc)where the values with primes indicate the desired conditions and the valueswithout primes indicate the experimental data. Temperature units are degreesCelsius. For both the baseline and the protected cases, the desired cabletemperature (T' ) was 90 *C [194 OF] and the desired ambient temperature (T' )was 40 'C [104 IF]. The measured baseline temperatures and ampacities and thecalculated baseline ampacity adjustment factors are provided in Table 3. Themeasured temperatures and ampacities and the calculated ampacity adjustmentfactors for the protected cables are provided in Table 4. For both thebaseline and protected cases, the average of the hot-spot cable temperaturesrecorded at 10-minute intervals during the final hour were used to calculatethe ampacity adjustment factor for that cable.The ampacity derating factor (ADF) for each cable type is the ratio of thereduction in current carrying capacity (protected ampacities) to the original
- . '_.<J IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula
- ADF Ibaslne jIProtected (100)IbasollneIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in TSI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-sted recalculations, whichwere needed to allow comparisons of the SNL/UL test resulte with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR(301) 504-1220
Attachments:
1. Table 1, 'Summary of Test ArticleCharacteristics," and Table 2, "Summaryof Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,'and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications ConcerningFire Barriers5. List of Recently Issued NRC Information Notices
- ytachment IIN94-22March 16, 1994 Table 1. Summary of Test Article CharacteristicsArticle Tetjye I Description Barrier Design1 3-Hour 6-inch-wide by 6-inch-high, Based on TSIFire solid-bottom, steel cable tray TechnicalEndurance based on Test Article 2 of TSI Note 20684,Report 82-5-355B, "Three-Hour Revision V,Fire Endurance Test on November 1985.Thermo-Lag 330-1 SublimingCoating Envelope System forWashington Public Power SupplySystem-Nuclear Projects,'l _____ _ .July 1982. ,_l2 3-Hour 12-inch-wide by 4-inch-high, Same as Article 1.Fire ladder-back, steel cable trayEndurance based on Test Article 4 of TSIReport 82-11-81, November 1982.3 3-Hour Same as Test Article 2. Methods documentedFire in TSI ReportEndurance 82-11-81,November 1982.4 Ampacity 12-inch-wide by 4-inch-high, Same as TestDerating ladder-back, steel cable tray Article 1.based on TSI Report 82-5-355F,lI July 13, 1982.Table 2. Summary of Fire Endurance Test Results(All times in Hours
- Minutes from the start of the test)Article Single Point .Average Time to TestTemperature Temperature Circuit DurationCriterion and Time Criterion and Time Faultto Exceed to Exceed1 200 -C [392 F] 158 *C [316 -F]1:05 1:20 1:16 2:302 200 *C [392 *F] 158 *C [316 *F]0:55 1:03 0:59 2:003 201 oC [394 OF] 159 C [318 *F ll 1:50 1:58 1:59 3:00
\-- itachment 2IN 94-22March 16, 1994 Table 3. Baseline (Unprotected Cable Tray)Ampacity Test Data and CalculationsCable Tc (0C) Ta (C) lI (Amps) AFc Ic (Amps)Size I8 AWG 91.1 io.5 23.8 0.996 23.74 AWG 91.2 40.5 38.0 0.995 37.82/0 92.0 40.5 115.0 0.988 113.6Table 4. Protected Cable TrayAmpacity Test Data and CalculationsCable Tc l-C) l Ta (C) j Ic (Amps) j AFC I'c (Amps)8 AWG 92.9 40.1 l 13.0 0.977 12.74 AWG 93.2 40.1 24.8 0.975 24.22/0 91.6 40.1 I 74.4 1 0.988 73.5Key for Tables 3 and 4:TC = Average of cable temperatures recorded at 10-minuteintervals during the final hour.To = Average of ambient (test chamber) temperaturesrecorded at 10-minute Intervals during the finalhour after reaching desired stable conditions.IC a Measured cable ampacity at the end of thefinal hour.AFC = Cable ampacity adjustment factor.I'C a Adjusted cable ampacit I tachment 3IN 94-22March 16, 1994 Table S. Comparative Summary of Ampacity Data and Derating FactorsCable Size Data Source Baseline Protected DeratingAmpacity Ampacity Factor(Amps) (Amps) (Percent)8 AWG SNL 23.7 12.7 46.4TSI1 17.46 14.64 16.15TSI2 20.38 13.89 31.84TS13 23.96 14.83 38.114 AWG SNL 37.8 24.2 36.0TSI1 35.77 29.74 16.86TS12 41.75 28.21 32.43TSI3 41.75 28.21 32.432/0 SNL 113.6 73.5 35.3TSP1 105.91 87.18 17.68TSI2 123.60 82.69 33.10TSI3 131.60 84.82 35.551 Data reported in TSI Report 82-5-355F, July 13, 1982.2 Inverted term in ampacity adjustment factor (AF) equation corrected.3 Measured individual conductor temperatures used to calculate ampacityadjustment factors for each cable siz _.>2tachment 4IN 94-22March 16, 1994 List of Generic Communications Concerning Fire BarriersInformation Notice 91-47, 'Failure of Thermo-Lag Fire Barrier Materialto Pass Fire Endurance Test," August 6, 1991Information Notice 91-79, "Deficiencies in the Procedures forInstalling Thermo-Lag Fire Barrier Materials," December 6, 1991Information Notice 92-46, 'Thermo-Lag Fire Barrier Material SpecialReview Team Final Report Findings, Current Fire Endurance Tests, andAmpacity Calculation Errors," June 23, 1992Bulletin 92-01, "Failure of Thermo-Lag 330 Fire Barrier System toMaintain Cabling in Wide Cable Trays and Small Conduits Free from FireDamage," June 24, 1992Information Notice 92-55, "Current Fire Endurance Test Results forThermo-Lag Fire Barrier Material," July 27, 1992Bulletin 92-01 Supplement 1, "Failure of Thermo-Lag 330 Fire BarrierSystem to Perform Its Specified Fire Endurance Function,"August 28, 1992Information Notice 92-82, "Results of Thermo-Lag 330-1 CombustibilityTesting," December 15, 1992Generic Letter 92-08, "Thermo-Lag 330-1 Fire Barriers,"December 17, 1992Information Notice 93-40, "Fire Endurance Test Results for ThermalCeramics FP-60 Fire Barrier Material," May 26, 1993Information Notice 93-41, "One Hour Fire Endurance Test Results forThermal Ceramics Kaowool, 3M Company FS-195 and 3M CompanyInteram E-50 Fire Barrier Systems," May 28, 1993 A 9chment 5Io-4-22March 16, 1994 LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to94-2194-2094-19Regulatory Requirementswhen No Operations arebeing PerformedCommon-Cause Failuresdue to InadequateDesign Control andDedicationEmergency DieselGenerator Vulnerabilityto Failure from ColdFuel OilAccuracy of Motor-Operated Valve Diag-nostic Equipment(Responses to Sup-plement 5 to GenericLetter 89-10)Strontium-90 Eye Appli-cators: Submission ofQuality Management Plan(QMP), Calibration, andUseRecent Incidents Resultingin Offsite ContaminationRadiation Exposures duringan Event Involving a FixedNuclear Gauge03/18/9403/17/9403/16/9403/16/9403/11/9403/03/9403/02/94All fuel cycle and materialslicensees.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All U.S. Nuclear RegulatoryCommission Medical UseLicensees.All U.S. Nuclear RegulatoryCommission material and fuelcycle licensees.All U.S. Nuclear RegulatoryCommission licensees author-ized to possess, use, manu-facture, or distributeindustrial nuclear gauges.94-1794-1694-15OL -Operating LicenseCP = Construction Permit IN 94-22March 16, 1994 current carrying capacity (baseline ampacities). The ADF for each cable typewas calculated using the following formula:ADF = baseline -protected (100)baselineIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the results reported by thevendor in BI Report 82-5-355F. Table 5 also shows the results ofrecalculations performed by SNL of the test data reported in TSIReport 82-5-355F. Detailed explanations of the two-step recalculations, whichwere needed to allow comparisons of the SNL/UL test results with the reportedvendor test results, will be documented in SNL Report SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager. diginslignedbyBrian K. Grimes, Director dan K. GrimesDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact: Steven West, NRR, (301) 504-1220
Attachments:
1. Table 1, "Summary of Test Article Characteristics," andTable 2, "Summary of Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,"and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, "Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications Concerning Fire Barriers5. List of Recently Issued NRCInformation NoticesDISTRIBUTIONSPLB R/F SWestLNorton, OIG GMulley, OIG EPawlik, RIII/Ol*SEE PREVIOUS CONCURRENCESPLB:DSSA*Tech Ed.* EELB:DE* SPLB:DSSA* SPLB:DSSA* OIG* (NoSWest RSanders CBerlinger CMcCracken MVirgilio §Mulley objection)02/23/94 02/15/94 03/10/94 03/03/94 03/0 v4 3/01/94OGCB:DORS* OGCB:DORS*RKiessel JLBirmingham03/08/94 03/11/94 03/IA/94OFFICIAL RECORD COPY 94-22.IN IN 94-XXMarch xx, 1994 current carrying capacity (baseline ampacities).was calculated using the following formula:The ADF for each cable typeADF = Ibaseline -protected (100)IbasaelineIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the vendor's test. Table 5also shows the results of recalculations performed by SNL of the test datareported in TSI Report 82-5-355F. Detailed explanations of the two-steprecalculations, which were needed to allow comparisons of the SNL/UL testresults with the vendor's test results, will be documented in SNLReport SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:Steven West, NRR, (301) 504-1220
Attachments:
1. Table 1, "Summary of Test Article Characteristics," andTable 2, "Summary of Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,"and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, "Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications Concerning Fire Barriers5. List of Recently Issued Information NoticesDISTRIBUTIONSPLB R/FLNorton, OIG*SEE PREVIOUSSWestGMulley, OIGCONCURRENCEEPawlik, RIII/OlSPLB:DSSA*Tech Ed.*SWest RSanders02/23/94 02/15/94EELB:DE*CBerlinger03/10/94SPLB:DSSA*CMcCracken03/03/94SPLB:DSSA*MVirgilio03/04/94OIG*GMulley03/01/94(Noobjection)OGCB:DORS*RKiessel03/08/94OFFICIAL RECORD COPYOGCB:DORS pl,4aJLBirminghaifi03/ //94IN_94_XX.SW4]D: DORSBGrimes03/ /94
&I I kY 94-XXMarch XX, 1994 current carrying capacity (baseline ampacities).was calculated using the following formula:The ADF for each cable typeADF = baseline protected (100)Ilal / tdbaselineIn this format, the ADF is expressed as a percentage drop in current-carryingcapacity. The calculated ampacity derating factors were 46.4 percent,36.0 percent, and 35.3 percent for the 8 AWG, 4 AWG, and 2/0 cables,respectively. Table 5 provides a comparative summary of the ampacity data andampacity derating factors from the SNL/UL test and the vendor's test. Table 5also shows the results of recalculations performed by SNL of the test datareported in TSI Report 82-5-355F. Detailed explanations of the two-steprecalculations, which were needed to allow comparisons of the SNL/UL testresults with the vendor's test results, will be documented in SNLReport SAND94-0146.This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor Regulation
Technical Contact:
Steven West, NRR, 301-504-1220
Attachments:
1. Table 1, "Summary of Test Article Characteristics," andTable 2, "Summary of Fire Endurance Test Results."2. Table 3, "Baseline (Unprotected CableTray) Ampacity Test Data and Calculations,"and Table 4, "Protected Cable Tray AmpacityTest Data and Calculations."3. Table 5, 'Comparative Summary of AmpacityTest Data and Derating Factors."4. List of Generic Communications Concerning Fire Barriers5. List of Recently Issued Information NoticesDISTRIBUTIONSPLB R/FLNorton, OIGGtiest4ulley, OIGEELB OC~erlinger/01/°/94SPLB:DSSA Tech Ed.ISWest RSanders02/aS/94 02/%s/94OGCB:DORR MGCB:DORSRKiesse! tugler03/9 /9i 02/ /94, RIII/O1S zDSSA SPLB:DypyCMcCracken MVI.rg ilio(5/3 /94 s/ g/94OIGG~ulley objection}A ll G/94 d,D:DORSBGrimes02/ /94 OFFICIAL RECORD COPY [G:\THERMOLA\IN_94_XX.SW4]