ML19296A927
| ML19296A927 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 02/12/1980 |
| From: | Randy Hall BROOKHAVEN NATIONAL LABORATORY |
| To: | Ferguson R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8002190469 | |
| Download: ML19296A927 (3) | |
Text
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BROOKHAVEN NATIONAL LABORATORY ASSOCMTED UNIVERSmES. INC.
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Cecccment cf 5,uc'ect Energy 51$1345-2144 February 12, 1980 Mr. Robert L. Ferguson Plant Systens Branch U.S. Nuclear Regulatory Commission Washington, D.C.
20555 RE: Calvert Cliffs, Fire Protection Review
Dear Bob:
Attached are our comments on the BG&E fire test procedure for cable and pipe penetrations for the Calvert Cliffs facility.
Respectfully yours,
'& $Y 00m-Robert E. Hall, Group Leader Reactor Engineering Analysis REH:EAM:sd attachment cc.:
J. Boccio R. Cerbone wo/att.
W. Kato E.- MacDougall V. Panciera wo/att.
E. Sylvester
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COMMENTS ON BG&E " FIRE TEST PROCEDURE FOR CABLE AND PIPE PENETRATION" January 11, 1980 For purposes of evaluating the BG&E test procedure it was compared with IEEE Standard 634-1978 "IEEE Standard Cable Penetration Fire Stop Qualification Test," and with the NRC position on cable penetration tests.
IEEE 634 recognizes that pressure differentials may be a factor in the fire resistance of a penetration seal, but does not specifically address the matter. The NRC position requires a pressure differential.
Our concern is that the proposed test procedure does not indicate that the fire tests will be conducted with a pressure differential across the penetra-tion seals (higher pressure on the exposed side). We recommend that the staff require the licensee to verify that the maximum pressure differential which may exist across the penetration seal during a fire will have no affect on its performance, or to provide the results of fire tests conducted with such pressure differential. We recommend that until an accpetable pressure dif-ferential requirement is developed that the pressure differential to be cen-sidered is the actual maximum pressure differential found in the plant during normal operations plus 2" of water based on our present conservative evalua-tions. When the specific values are known they should be utilized to replace this interum generic approach.
Section E.2 of the BG&E test procedure indicates that, except for penetra-tions detailed in Figures 3, 4 and 5, penetrations which pass the test will be qualified for installation in either a horizontal or vertical orientation.
The penetration detailed in Figure 6 is not symmetrical, and would probably have to be tested in both directions in order for it to be used in a vertical configuration. The licensee should be requested to modify its test procedure or penetration design accordingly.
Appendix A of the BG&E test procedure, in describing the installation de-tails of Figure 2, indicates that Kaowool would be hand-packed around indivi-dual cables in each tray. This would seem to be a very time consuming proce-dure, especially in a plant the size of Calvert Cliffs. The licensee should be requested to verify that this is actually the way Kaowool is installed in cable tray penetrations at the plant, and that adequate QA procedures exist to assure adherence to this design.
Appendix A of the BG&E test procedures also indicates that cable trays numbers 1, 2, and 3, and the penetration detailed in Figure 3 are depictions of existing conditions at Calvert Cliffs. Comparison with Figure D-2 (ex-isting cable tray penetrations) of the licensee's March 15, 1977 Fire Protec-tion Program Evaluation indicates that the depth of Kaowool in the design to be tested is 12 inches greater than in the existing penetrations. The licensee should be requested to modify its test designs accordingly.
Section C.5 of the BG&E procedure indicates that wireways will extend only 2 inches on the unexposed side of the penetration.
IEEE 634-1978, Section 5.3.4 requires that raceways protrude 3 to 5 feet on the unexposed side of the penetration and the National Electrical Code,1978 edition, defines wireway as a fonn of raceway. We recommend that the licensee be requested to modify his procedure accordingly.
Sections C.6 and C.11 of the BG&E test procedure indicate that conduit wireways and cable trays will be filleo to a specific proportion of their capacity.
IEEE 634-1978, Section 5.2.2, requires that range of percent fill should be tested. The licensee should be requested to modify its procedure accordingly, to accanmodate both the maximum and minimum fill of conduit, wireways, and trays in the plant. The BG&E test procedure has two acceptance criteria only.
IEEE 634-1978 includes these two, and a third, relating to the maximum temperature on the unexposed side of the penetration (Section 6.1.2).
The licensee should be requested to amend its testing procedure to include this third criteria.
The non-silicone rubber cables are listed in C.10 as XLP or EPR. Ap-pendix C lists these only as XLP, we recommend that this be clarified. We also recamnend that the staff request the licensee to review the non-silicone type of cables to be assured that XLP and/or EPR are the most conservative types chosen.
That is, that XLP and/or EPR have the poorest fire protection properties of the non-silicone cables used in the plant.
Section D.4 of the BG&E test procedure indicates that the licensee pro-posed to plug (with Kaowool) any openings which may develop in the test slab during the test. Neither IEEE 634-1978 nor a draft ASTM test method on penetration fire stops addresses such a procedure. Use of the Kaowool to prevent extreme deviations in furnace temperature may be acceptable, but its use to prevent deterioration of adjacent penetration should not be.
IEEE 634-1978, Appendix 2 addresses the issue of minimum distance between adjacent elements in an opening. The licensee should be requested to forego the use of Kaowool for this purpose, and be prepared to rerun the test if necessary.
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