Information Notice 1994-34, Thermo-LAG 330-660 Flexi-Blanket Ampacity Derating Concerns

Thermo-LAG 330-660 Flexi-Blanket Ampacity Derating Concerns

ML031060554
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	05/13/1994
From:	Grimes B Office of Nuclear Reactor Regulation
To:
References
-nr IN-94-034, NUDOCS 9405090108
Download: ML031060554 (12)

-1 UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 May 13, 1994 NRC INFORMATION NOTICE 94-34: THERMO-LAG 330-660 FLEXI-BLANKET AMPACITY

DERATING CONCERNS

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information

notice to alert addressees to a potential problem involving the use of

nonconservative ampacity derating data by licensees based on previous

representations by the vendor, Thermal Science, Inc. (TSI). It is expected

that recipients will review the information for applicability to their

facilities and consider actions, as appropriate, to avoid similar problems.

However, suggestions contained in this information notice are not NRC

requirements; therefore, no specific action or written response is required.

Description of Circumstances

The vendor, TSI, stated in a purchase document, OTSI's Bid Document 618,"

dated June 25, 1986, for Northeast Utilities Service Company (Millstone

Units 1 and 2) that the Thermo-Lag 330-660 Flex-Blanket material will produce

test results similar to those of the Thermo-Lag 330-1 material. For example, the vendor cited a 7.47 percent ampacity derating factor for the Thermo- Lag 330-1 material based on reported test results for a 1-hour-rated fire

barrier conduit system.

On November 8, 1993, the NRC staff wrote to TSI requesting information

regarding the ampacity derating data provided licensees for the application of

the Thermo-Lag 330-660 Flexi-Blanket fire barrier system.

On December 22, 1993, TSI responded stating that Texas Utilities Electric

Company had recently conducted an ampacity derating test at the Omega Point

Test Laboratories. The test, using a 1-hour design (three 0.64 cm

[0.250 inch] layers) of the Thermo-Lag 330-660 Flexi-Blanket material, had

resulted in a 21.2 percent ampacity derating factor for a 3C/#6 AWG Air Drop

configuration. In addition, the vendor stated that, to the best of its

knowledge, no ampacity derating test has been performed on the 3-hour design

(five 0.64 cm [0.250 inch] layers) of the Thermo-Lag 330-660 Flexi-Blanket

fire barrier system.

9405090108 ?D)V 't tE £eLtc-e- lqfia03q ¶Lst Ia3 At/7/f X0 1

Vt V IN94-34 May 13, 1994 Attachment 1 contains a list of the organizations that TSI identified as

having purchased the Thermo-Lag 330-660 Flexi-Blanket material for use in

nuclear power generating plants.

Discussion

Title 10 of the Code of Federal Regulations, Part 50, Appendix A, General

Design Criterion (GDC) 17, "Electric power systems," if applicable, requires

that onsite and offsite electric power systems be provided to permit the

functioning of structures, systems, and components important to safety. The

safety function of either electrical power system (assuming the other system

is not functioning) is to provide sufficient capacity and capability to ensure

that vital functions are maintained. Cables routed in electrical raceways are

derated to ensure that systems have sufficient capacity and capability to

perform their intended safety functions. Other factors that affect ampacity

derating include cable fill, cable loading, cable type, raceway construction, and ambient temperature.

Cable derating calculations that are based on inaccurate or nonconservative

derating factors could result in the installation of undersized cables or

overfilling of raceways. Either of these conditions could cause operating

temperatures to exceed design limits within the raceways, thereby reducing the

expected design life of the cables. TSI stated in the 1986 procurement

document referenced above that the Thermo-Lag 330-660 material will produce

similar ampacity results as those of the Thermo-Lag 330-1 material. Because

of the wide range of ampacity derating factors documented for various Thermo- Lag materials, some licensees may not have adequately accounted for the

insulating effects of the Thermo-Lag 330-660 material in their derating

analyses.

The National Electrical Code, Insulated Cable Engineers Association

publications, and other industry standards provide general ampacity derating

factors for open-air installations, but do not include derating factors for

fire barrier systems. The Insulated Conductors Committee of the Institute of

Electrical and Electronics Engineers (IEEE) Power Engineering Society, Task

Force 12-45, has been developing IEEE Standard Procedure P848, "Procedure for

the Determination of the Ampacity Derating of Fire Protected Cables," for use

as an industry standard. The industry consensus standard development process

may result in the formulation of a uniform technical approach to the deter- mination of ampacity derating factors for cables enclosed by fire barrier

systems.

Related Generic Communications

In NRC Information Notice (IN)92-46, "Thermo-Lag Fire Barrier Material

Special Review Team Final Report Findings, Current Fire Endurance Tests, and

Ampacity Calculation Errors," the staff informed licensees that a licensee had

discovered a mathematical error in the calculation of the ampacity derating

IN94-34 v May 13, 1994 factor as published in an Industrial Testing Laboratories, Incorporated, test

report. A preliminary assessment of the use of lower-than-actual ampacity

derating factors indicates that the Thermo-Lag barrier installations may allow

cables to reach temperatures that exceed their ratings, which could accelerate

cable aging.

In IN 94-22, 'Fire Endurance and Ampacity Derating Test Results for 3-Hour

Fire-Rated Thermo-Lag 330-1 Fire Barriers," the staff informed licensees of

the preliminary results of fire endurance and ampacity derating tests

conducted by NRC at the Underwriters Laboratories, Incorporated, during

December 1993. The principal objective of the tests was to evaluate the

performance of the barriers against the results of tests previously reported

by TSI.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuc ar

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660

Flexi-Blanket Thermal Barrier Material

2. List of Recently Issued NRC Information Notices

,j Attachment No. 1 IN 94-34 May 13, 1994 LICENSEES WHO PURCHASED

THERMO-LAG 330-660 FLEXI-BLANKET THERMAL BARRIER MATERIAL'

Utility I Facility

Carolina Power & Light Co. Brunswick

Cleveland Electric Illuminating Co. Perry Nuclear Plant

Commonwealth Edison Braidwood Station

Entergy Operations, Inc. Waterford 3

Consumers Power Palisades

Florida Power Corporation Crystal River Unit 3

Fluor Engineers Co. San Onofre

Georgia Power E. I. Hatch

Plant Vogtle

Gulf States Utilities2 River Bend

GPU Nuclear Oyster Creek

-Three Mile Island

Long Island Lighting Shoreham

Iowa Electric Duane Arnold Plant

Northern States Power Prairie Island

South Carolina Electric & Gas Co. Virgil C. Summer

Tennessee Valley Authority Browns Ferry

Watts Bar

Toledo Edison Co. Davis Besse Power Station

Texas Utilities Electric Comanche Peak Units 1 and 2 Washington Public Power Supply System WNP-2

1 From TSI letter to NRC dated December 22, 1993.

2Licensee is now Entergy Operations, Inc.

AtV_ chment No. 2 IN 94-34 May 13, 1994 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

94-33 Capacitor Failures in 05/09/94 All holders of OLs or CPs

Westinghouse Eagle 21 for nuclear power reactors.

Plant Protection Systems

93-53, Effect of Hurricane 04/29/94 All holders of OLs or CPs

Supp. 1 Andrew on Turkey Point for nuclear power reactors.

Nuclear Generating

Station and Lessons Learned

94-32 Revised Seismic Hazard 04/29/94 All holders of OLs or CPs

Estimates for nuclear power reactors.

94-31 Potential Failure of 04/14/94 All holders of OLs or CPs

Wilco, Lexan-Type HN-4-L for nuclear power reactors.

Fire Hose Nozzles

90-68, Stress Corrosion Cracking 04/14/94 All holders of 01 or CPs

Supp. 1 of Reactor Coolant Pump for pressurized water

Bolts reactors.

Leaking Shutdown Cooling 04/12/94 All holders of OLs or CPs

Isolation Valves at for nuclear power reactors.

Cooper Nuclear Station

94-29 Charging Pump Trip during 04/11/94 All holders of OLs or CPs

a Loss-of-Coolant Event for pressurized water

Caused by Low Suction reactors.

Pressure

92-51, Misapplication and 04/12/94 All holders of OLs or CPs

Supp. 1 Inadequate Testing of for nuclear power reactors.

Molded-Case Circuit

Breakers

Potential Problems with 04/05/94 All holders of OLs or CPs

Fire-Barrier Penetration for nuclear power reactors.

Seals

OL - Operating License

CP - Construction Permit

IN 94-34 May 13, 1994 factor as published in an Industrial Testing Laboratories, Incorporated, test

report. A preliminary assessment of the use of lower-than-actual ampacity

derating factors indicates that the Thermo-Lag barrier installations may allow

cables to reach temperatures that exceed their ratings, which could accelerate

cable aging.

In IN 94-22, "Fire Endurance and Ampacity Derating Test Results for 3-Hour

Fire-Rated Thermo-Lag 330-1 Fire Barriers," the staff informed licensees of

the preliminary results of fire endurance and ampacity derating tests

conducted by NRC at the Underwriters Laboratories, Incorporated, during

December 1993. The principal objective of the tests was to evaluate the

performance of the barriers against the results of tests previously reported

by TSI.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Oiighial Ugnid f

Brian K.Grimei

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660

Flexi-Blanket Thermal Barrier Material

2. List of Recently Issued NRC Information Notices

• see previous concurrence

OFFICE *OGCB\DORS *Tech Editor *EELB\DE *C:\EELB\DE

NAME RJKiessel MMejac RVJenkins CHBerlinger

DATE 4/12/94 T,

1 4/14/94

-

4/18/94 4 4/21/94 OFFICE *D: DE\NRR *C:OGCB\DORS D: w

NAME BWSheron AJKugler fB e`(e

DATE 4/22/94 5/05/94 1 5/ /94 Document Name: 94-34.IN

IN 94- xx

May xx, 1994 factor as published in an Industrial Testing Laboratories, Incorporated, test

report. A preliminary assessment of the use of lower-than-actual ampacity

derating factors indicates that the Thermo-Lag barrier Installations may allow

cables to reach temperatures that exceed their ratings, which could accelerate

cable aging.

In IN 94-22, "Fire Endurance and Ampacity Derating Test Results for 3-Hour

Fire-Rated Thermo-Lag 330-1 Fire Barriers," the staff informed licensees of

the preliminary results of fire endurance and ampacity derating tests

conducted by NRC at the Underwriters Laboratories, Incorporated, during

December 1993. The principal objective of the tests was to evaluate the

performance of the barriers against the results of tests previously reported

by TSI.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660 Flexi-Blanket Thermal Barrier

Material

2. List of Recently Issued NRC Information Notices

• see previous concurrence

OFFICE *OGCB\DORS *Tech Editor *EELB\DE *C:\EELB\DE ]

NAME RJKiessel MMejac RVJenkins CHBerlinger l

DATE 4/12/94 4/14/94 4/18/94 4/21/94

• I. ...

OFFICE *D:DE\NRR C:OGCB\DORS D:DORS\NRR

NAME BWSheron AJKugler e BKGrimes S

DATE 4/22/94 1 5/S-/94 5/ /94 Document Name: G:\RJK\NRCINS\NRCIN.421

IN 94- xx

April xx, 1994 factor as published in an Industrial Testing Laboratories, Incorporated, test

report. A preliminary assessment of the use of lower-than-actual ampacity

derating factors indicates that the Thermo-Lag barrier installations may allow

cables to reach temperatures that exceed their ratings, which could accelerate

cable aging.

In IN 94-22, "Fire Endurance and Ampacity Derating Test Results for 3-Hour

Fire-Rated Thermo-Lag 330-1 Fire Barriers," the staff informed licensees of

the preliminary results of fire endurance and ampacity derating tests

conducted by NRC at the Underwriters Laboratories, Incorporated, during

December 1993. The principal objective of the tests was to evaluate the

performance of the barriers against the results of tests previously reported

by TSI.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660 Flexi-Blanket Thermal Barrier

Material

2. List of Recently Issued NRC Information Notices

• seP nrevious

I-. - concurrence

- --

OFFICE *OGCB\DORS *Tech Editor *EELB\DE *C:\EELB\DE

NAME . RJKiessel MMejac RVJenkins CHBerlinger

DATE 4/12/94 4/14/94 4/18/94 4/21/94

- I I

OFFICE *D:DE\NRR C:OGCB\DORS D:DORS\NRR

NAME BWSheron AJKugler BKGrimes

l

DATE 1 4/22/94 5/ /94 5/ /94 Document Name: G:\RJK\NRCINS\NRCIN.421

IN 94- xx

April xx, 1994 conducted by NRC at the Underwriters Laboratories, Incorporated, during

December 1993. The principal objective of the tests was to evaluate the

performance of the barriers against the results of tests previously reported

by TSI.

This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660 Flexi-Blanket Thermal Barrier

Material

2. List of Recently Issued NRC Information Notices

/,t d21

• see nrevious concurrence

OFFICE *OGCB\DORS *Tech Editor EELB\DE C `\t

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NAME RJKiessel MMejac RVJenkins 4 CHBerlinger

DATE 1 4jI94 4/14/94 4/L/942 bL 4 X /94 j

V 71 OFFICE 6: OKNRR C:OGCB\DORS D:DORS\NRR

NAME BWkdon AJKugler BKGrimes

DATE 4/iZ,/94 4/ /94 4/ /94 Document Name: :\ G\JK\NRGIN5\NRULN.4Z1 a0Alp

Attachments:

1. Licensees Who Purchased Thermo-Lag 330-660 Flexi-Blanket Thermal Barrier

Material

2. List of Recently Issued NRC Information Notices

• Cev nrwinmic rnlrinrrenre

OFFICE OGCB\DORS 1 ITech Editor EELB\DE C:\EELB\DE

NAME Riessel X . M*J4vC-

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DATE 4/)r./94 4/1fi/94 j 4/ /94 4/ /94 OFFICE D:DE\NRR C:OGCB\DORS D:DORS\NRR

NAME BWSheron AJKugler BKGrimes

DATE 4/ /94 4/ /94 4/ /94 Ii

Document Name: b:NKJKNNK~lNb\NK~lN.4Z1

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IN 94-XX

March xx, 1994 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regulation (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ronaldo V. Jenkins, NRR

(301) 504-2985 Attachment:

List of Recently Issued NRC Information Notices

• See previous concurrence

Document Name: G:\SHARED\INTHERM.660

D/DORS:NRR C/OGCB:DORS:NRR

BKGrimes GHMarcus

3/ /94 3/ /94 EELB:DE:NRR SC/EELB:DE:NRR OGCB:DORS:NRR RPB:ADM

• RVJenkins PGill U TechEd*-)l

2/16/94 2/.26/94 3/ /94 2/22/94

IN 94-XX

January xx, 1994 This inform tion notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

the technical contact listed below or the appropriate Office of Nuclear

Reactor Regula ion (NRR) project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contact: Ron ido V. Jenkins, NRR

(301 504-2985 Attachment:

List of Recently Issued NRC I formation Notices

Document Name: G:\SHARED\ RM.660

D/DORS:NRR C/OGCB:DORS:NRR

BKGrimes GHMarcus

2/ /94 2/ /94 EELB:DE:NRR SC/EELB:DE:NRR C/EELB:DE. RR OGCB:DORS:NRR RPB:ADM

RVJenkinsooev~ie PGill CHBerlinge TechEd*

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