Regulatory Guide 1.131
| ML003740128 | |
| Person / Time | |
|---|---|
| Issue date: | 08/31/1977 |
| From: | Office of Nuclear Regulatory Research |
| To: | |
| References | |
| RG-1.131 | |
| Download: ML003740128 (4) | |
U.S. NUCLEAR REGULATORY COMMISSION August 1977 REGULATORY GUIDE
OFFICE OF STANDARDS DEVELOPMENT
REGULATORY GUIDE 1.131 QUALIFICATION TESTS OF ELECTRIC CABLES, FIELD SPLICES,
AND CONNECTIONS FOR LIGHT-WATER-COOLED
NUCLEAR POWER PLANTS
A. INTRODUCTION
the Insulated Conductors Committee of the Power Criterion III, "Design Control," of Appendix B, Engineering Society of the Institute of Electrical and
"Quality Assurance Criteria for Nuclear Power Electronics Engineers, Inc. (IEEE), approved by the Plants and Fuel Reprocessing Plants," to 10 CFR IEEE Nuclear Power Engineering Committee, and Part 50, "Licensing of Production and Utilization subsequently approved by the IEEE Standards Board Facilities," requires that, where a test program is on February 28,1974. It was agooved as an ANSI
used to verify the adequacy of a specific design standard, ANSI N41.10-1975 1hpril
30, 1975. The feature, it include suitable qualification testing of a standard delineates proce e developing a prototype unit under the most adverse design condi program for qualificatio festingg cables, field tions. This regulatory guide describes a method ac splices, and connectioj* It plements IEEE Std 323-1974, "IEEE St;ioualifying Class IE
ceptable to the NRC staff for complying with the Equipment for N aear , enerating Stations,"
Commission's regulations with regard to qualifica which describe as' re ements for equipment tion testing of electric cables, field splices, and con qualification. I d'td
23-1974 is endorsed, with nections for service in light-water-cooled nuclear certain exoion'*f Regulatory Guide 1.89, powe~r plants to ensure that the cables, field splices, "Qualificati' C s IEE Equipment for Nuclear and connections can perform their safety-related PowerAtlntL
functions.' The fire test provisions of this guide do not apply to quanttication for an installed contlgura- tion. rtl' te-' IEEE Std 383-1974 was issued, s ab atories and cable testing facilities ex r% c difficulty in producing a consistent flame by using the burner and flame source
B. DISCUSSION
cedures specified in the standard. An IEEE task IE S investigation
3e into the problem was eventually IEEE Std 383-1974, "IEEE Standard for pe expanded to include an evaluation of various flame Test2 of Class IE Electric Cables, Field e sources to determine if the 70,000 Btu/hr flame Connections for Nuclear Power eera i source specified in the standard was correct for use in Stations," 3 was prepared by Working G p1 of fire qualification testing. The investigation found that inconsistencies in the flame source were traceable to
'Regulatory Guide 1.29, "Seismic Design Classification, provides the inadvertent use of incorrectly sized burners dur guidance with regard to identifying electric cables, field splices, ing certain tests.
and connections to which the desi rification requirements of Appendix B to 10 CFR Part 50 * 1 .. A
2 As used in this regulatory guide' t alification test" and A series of tests to determine if the correct flame
"type test" are synonymous. source had been selected was conducted, and the
3 Copies may be obtain he I titute of Electrical and results, as evaluated by the IEEE task force and the Electronics Engineers, nited neering Center, 345 East 47th NRC staff, indicated no basis for changing the 70,000
Street, New York, 0017. Btu/hr. Investigation into fire testing is continuing by RE* TORY GUIDES Comments should be sent to the Secretary of the Commission, US. Nuclear Regu Regulatory Guides a L d to describe and make available to the public methods latory Commission, Washington, D.C. 20555, Attention:' Docketing and Service acceptable to the NR q .of implementing specific parts of the Commission's Branch.
r e g u la t io n s , to d e l i en~
a t eN l u es u se d b y t h e st a f f i n ev a l u a t i n g sp e c if ic p r o b le m sT h gud s u ei u d int ef l o ng en b ad iv i n or postulated accidents, or provide guidance to applicants. Regulatory Guides The guides e issued in the following ten broad divisions are not substitutes for regulations, and compliance with them is not required.
1. Power Reactors 6. Products Methods and solutions different from those set out in the guides will be accept-
2. Research and Test Reactors 7. Transportation able if they provide a basis for the findings requisite to the issuance or continuance
3. Fuels and Materials Facilities 8. Occupational Health of a permit or license by the Commission.
M
4. Environmental and Sitina o Anti , .. ...
Comments and suggestions for improvements in these guides are encouraged at all Materials and Plant Protection e times, and guides will be revised, as appropriate, to accommodate comments and Requests for single copies of issued guides which may be reproduced)
to reflect new information or experience. However, comments on this guide,if or for place meet on an automatic distribution list for single copies of future guides received within about two months after its issuance, will be particularly in specific useful in divisions should be made in writing to the US. Nuclear Regulatory evaluating the need for an early revision. Commission, Washington, D.C. 20555, Attention: Director, Division of Document Control.
IEEE and NRC, and significant results will be incor quence of environmental extremes that simulate porated in future revisions of this guide. the most severe postulated conditions of a design basis event and specified conditions of The flame tests covered by Section 2.5 of the stan installation. Type tests shall demonstrate dard provide a test primarily of the self-extinguishing margin by application of multiple transients, in tendency of the cable insulation material. These tests creased level, or other justifiable means.
are conducted with cables in a specific configuration Satisfactory performance of the cable will be and subjected to a defined fire source. However, the evaluated by electrical and physical measure fire resistance of cables may vary significantly under ments appropriate to the type of cable during or different environmental conditions, cable configura following the environmental cycle, or both. The tions, and fire sources. It should be recognized that factors for margin given in Section 6.3.1.5 of the objective of the flame test is to provide guidance IEEE Std 323-1974 shall be used where ap for the selection of fire-resistant cables rather than to plicable.
establish the adequacy of the installation of cables in a nuclear power plant. Adequacy of cables as instal "The values of pressure, temperature, radia led depends on many factors. Morever, the adequacy tion, chemical concentrations, humidity, and of the cable system as installed depends on other fac time in IEEE Std 323-1974 do not represent ac tors in addition to the properties of the cables. For ceptable limits for all nuclear power stations.
example, cable separation criteria are delineated in The user of this standard shall ensure that the Regulatory Guide 1.75, "Physical Independence of values used in the required type tests represent Electric Systems," and fire protection guidelines are acceptable limits for the service conditions in delineated in Regulatory Guide 1.120, "Fire Protec which the cable or connections will be instal tion Guidelines for Nuclear Power Plants." led."
IEEE Std 383-1974 is concerned with cables both 3. In lieu of Section 2.1, "Introduction," the fol inside and outside the containment and establishes lowing should be used:
procedures for simulating operating conditions so that type testing will be adequate for the intended ser "Type tests deqcribed in this document are vice conditions. It covers normal operating and design basis event conditions, except that the fire test is a reference configuration and flame rather than the design basis configuration and flame.
methods that shall be used to qualify electrical cables, field splices, and connections for use in nuclear power generating stations. Tests of the cable or connection assembly, as applicable, I_
shall then supplement the cable tests in order to
C. REGULATORY POSITION
qualify the connections and other aspects uni que to planned usage.
Conformance with the requirements of IEEE Std 383-1974, "IEEE Standard for Type Test of Class IE "The values of pressure, temperature, radia Electric Cables, Field Splices, and Connections for tion, chemical concentrations, humidity, and Nuclear Power Generating Stations," is acceptable time indicated in IEEE Std 323-1974 do not for qualifying electric cables, field splices, and con represent acceptable limits for all nuclear power nections as components (Fite test provisions do not generating stations.
apply to qualification for an installed configuration) "The user of this guide shall ensure that the for service in light-water-cooled nuclear power plants values used in the required type tests represent to ensure that the cables, field splices, and connec acceptable limits for the service conditions in tions can perform their safety-related function sub which the cable, or connections, or both, will be ject to the following: installed.
1. In lieu of Section 1.3.4.2.3, "Other Design Basis "Results of prior tests that are being used as the Events," -the following should be used: bases for the present tests shall be referenced in the documentation."
"The remainder of the complete spectrum of design basis events (e.g., events such as a steam 4. In lieu of Section 2.3.2, "Long-Term Physical line break) shall be considered in case they Aging Properties," the following should be used:
represent different types or more severe hazards "Aging data shall be submitted to establish to cable operation." long-term performance of the insulatio
n. Data
2. In lieu of Section 1.3.5.3, "Test Design Basis may be evaluated using the Arrhenius tech Event," the following should be used: nique. A minimum of 3 data points, including
136°C and two or more others at least 10°C
""Type tests for design basis event conditions apart in temperature, shall be used.
shall consist of subjecting non-aged and aged "If there is not sufficient evidence that ac cables, field splices, and connections to a se- celerated aging techniques can reliably produce
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end-of-life conditions, the following ongoing "The fire test provisions of the standard are qualification procedure should be used: useful in screening out cable insulation
"Ongoing Qualification Procedure-Some types materials that are inadequately self extinguishing, but they shall not be construed as of cables, field splices, and connections (hereafter referred to only as cables) may not qualification of any installed cable system con respond in a representative manner to ac figuration. If field splices are to be used in cable trays, special provisions -shall be made to celerated aging techniques to establish end-of design-life conditions. Consequently, the demonstrate that the fire retardant properties of the cable are not altered unacceptably in an qualified life would be less than the required adverse way by the field splice."
design life. There are two suggested methods of achieving long-term (design life) qualification: 8. Section 2.5.4.2-Vertical tray configuration (a) After a planned period less than the should be used and understood to mean perpen qualified life of the cable has been reached, dicular to the plane of the horizon.
representative cables should be replaced with new cables and the removed cables subjected to 9. In lieu of Section 2.5.4.4, the following should a qualification test similar to that performed be used:
prior to installation. This test should include additional accelerated aging. Successful com "The gas burner flame source shall consume pletion of this test extends the qualified life of propane gas so as to release approximately the installed cables. This procedure should be 70,000 Btu per hour at an air-gas ratio of 5 to 1.
repeated until the qualified life equals or ex Natural grade propane shall be used. The ceeds the required design life. (b) Additional procedure detailed below shall be followed:"
identical cables should be installed in a nuclear power generating station location where power 10. In lieu of the first sentence of Section 2.5.4.4.1, loading and service conditions equal or exceed the following should be used:
those of the cable to be qualified. A cable should be removed after a planned period less "The ribbon gas burner' shall be mounted than the previously qualified life and subjected horizontally such that the flame impinges on to a qualification test similar to that performed the specimen midway between the tray rungs prior to installation. This test should include ac and so that the burner face is in front of and 4 celerated aging. Successful completion of this inches from the cable and approximately 2 feet test extends the qualified life of the installed above the bottom of the tray."
cable. Sufficient additional identical cables should be initially installed in order that the 11. In lieu of Section 2.5.4.4.3, the following above procedure can be repeated until the should be used:
qualified life 'equals or exceeds the required design life. "Flame size will normally be achieved when the propane flow is 27.8 standard ft3 per hour and
"If the above methods demonstrate that the the air flow is 139 standard ft' per hour."
qualified life is less than the design life, a periodic replacement plan should be in stituted." 12. Section 2.5.4.5 is not endorsed by this regulatory guide.
5. The radiological source term and exposure rate simulating LOCA conditions referred to in Section 13. The recommendations indicated by "should"
2.4.2, "Radiation Exposure-Total," should be ob and the options indicated by "may" in the sections of tained from Regulatory Guide 1.89 rather than from IEEE Std 383-1974 indicated below have sufficient IEEE Std 323-1974. importance to be treated the same as requirements of the standard:
6. In lieu of Section 2.5.1, "General," the follow ing should be used: a. Section 1.3.1, "Cable Description"
b. Section 1.3.2, "Field Splices or Connection
"This section describes the method for type Description"
testing of grouped cables via the vertical tray c. Section 1.3.4.1, "Meeting Service Conditions";
flame test to determine their relative self the first sentence.
extinguishing tendencies. Testing shall include both aged and unaged cable specimens." 'An American Gas Furnace Co. 10-in, 11-55 drilling, ribbon-type, catalog no. 10X 11-55 with an air-gaq Venturi mixer, catalog no.
7. In lieu of Section 2.5.2.2, the following should 14-18 (2 lbf/in2 max. gauge pressure) is the only presently be used: available model that has been found satisfactory for purposes of these tests.
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d. Section 1.3.4.2.1, "Design Basis Event flame resistance test in accordance with ASTM
LOCA" D2220-68.
e. Section 1.4.1, "General"
f. Section 1.4.3, "Test Results" 14. Section 3, "References," of IEEE Std 383-1974 g. Section 1.4.4, "Test Evaluation" lists additional applicable IEEE standards. The h. Section 2.2, "Type Test Samples" specific applicability or acceptability of these i. Section 2.3.3, "Thermal and Radiation Ex referenced standards has been or will be covered posure" separately in other regulatory guides, where ap j. Section 2.3.3.3 propriate.
k. Section 2.3.3.4 i. Section 2.4.3, "LOCA Simulation"
D. IMPLEMENTATION
m. Section 2.4.3.1 The purpose of this section is to provide informa n. Section 2.4.3.2 tion to applicants and licensees regarding the NRC
o. Section 2.4.4, "Post LOCA Simulation Test" staff's plans for utilizing this regulatory guide.
p. Section 2.5.2.1 q. Section 2.5.4.3 Except in those cases in which the applicant r. Section 2.5.4.4.2 proposes an acceptable alternative method, the s. Section 2.5.5, "Evaluation" method described herein for complying with specified t. Section 2.5.6, "Instrument Cable and Single portions of the Commission's regulations will be used Conductors from Multiconductor Assembly"; by the staff in evaluating all construction nermit ap the recommendation that the tested cable pass a plications docketed after May 1, 1978.
UNITED STATES
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