0CAN018304, Responds to NRC Re Violations Noted in IE Insp Repts 50-313/82-15 & 50-368/82-12.Closed End Rigid Metal Conduit Penetrating Frame Will Not Significantly Affect Fire Resistant Ability of Door Assemblies

Responds to NRC Re Violations Noted in IE Insp Repts 50-313/82-15 & 50-368/82-12.Closed End Rigid Metal Conduit Penetrating Frame Will Not Significantly Affect Fire Resistant Ability of Door Assemblies

ML20071C340
Person / Time
Site:	Arkansas Nuclear
Issue date:	01/12/1983
From:	John Marshall ARKANSAS POWER & LIGHT CO.
To:	Seidle W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20071C339	List: 0CAN018304, Responds to NRC Re Violations Noted in IE Insp Repts 50-313/82-15 & 50-368/82-12.Closed End Rigid Metal Conduit Penetrating Frame Will Not Significantly Affect Fire Resistant Ability of Door Assemblies
References
0CAN018304, CAN18304, NUDOCS 8303010685
Download: ML20071C340 (2)

Text

ARKANSAS POWER & LIGHT COMPANY POST OFFICE BOX 551 LITTLE ROCK, ARKANSAS 72203 (501) 371-4000 January 12, 1983 q

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Mr. W. C. Seidle, Chief Reactor Project Branch #2 U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76011

SUBJECT:

Arkansas Nuclear One - Units 1 & 2 Docket Nos. 50-313 and 50-368 License Nos. DPR-51 and NPF-6 Supplemental Response to Notice of Violation and Deviation

[ Gentlemen:

Please refer to your letter on this subject dated November 12, 1982, in which you requested additional information providing details of how we concluded that the electrical conduit penetration of fire door frames, when sealed, provides protection at least equivalent to that required of the fire barriers.

We have reviewed fire rating practices and industry guidel:aes/ standards such as ASTM E152, NFPA803, 251, and 252. Based on the results of this review, it is our judgement that conduit penetrations such as those in the door frames at ANO do not significantly affect the fire resistance ability of the door assemblies. In fact, we do not see significant difference between these penetrations and other penetrations through fire walls. In this respect, the procedures are essentially the same.

As for the door assemblies, they are rated in hours according to their ability to withstand a standard fire test, such as that described in ASTM E152 (no significant differences between other standards). That test requires a fire door to remain in its opening throughout the performance of the test without exceeding allowable movements or distortions at the door edges or latch location and without developing openings through the assembly. Although such testing for our particular case at hand has not been done, it is our engineering judgement a closed end rigid metal conduit penetrating the frame (not the door) in the quantity and locations at ANO will not cause a door to fail the ASTM E152 test and will not affect its performance with respect to fire resistance.

8303010685 830225 PDR ADOCK 05000313 G PDR MFMBEA MtOOLE SOUTH UTIUTIES SYSTEM L.

Mr. W. C. S: idle January 12, 1983

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Concerning sealing of these penetrations, we have applied a non-shrink grout to the small opening around the 3/4-inch nominal diameter conduit on both sides of the door frame (drilled holes are approximately 1-inch diameter).

This grout will serve to prevent the passage of hot gases, smoke, and flames from one side to the other. The grout is a typical high compressive type used at AN0 for grouting around such items as wall pipe penetrations. As stated earlier, we consider this case, for all practical purposes, the same as a wall penetration. Therefore, the seal should be the same.

The fire door assemblies are approved by Underwriters' Laboratories (U.L.)

for installation with or without grout filling of the frame. It is our information that the need for grouting (for this application) is an option for the user to determine based upon the assembly stability required when installed. However, the presence, or not, of grouting in this area does not detract from the U.L. rating. We have made the obvious conclusion, therefore, that where the door ftames are hollow as installed, only the openings at the conduit penetration (on both sides of the frame) need to be sealed. However, where the door frames have been filled for purposes of stability, the penetration must be sealed the full depth of the penetration.

We believe such a judgement is completely within our responsibility and, in this case, is entirely satisfactory and applicable. We have included for your review Specification CRD-C 588 for nonshrink grout, Specification C-2406 for application of the grout, and prints of drawings A-2508, A-2521 (SHT.1), and A-307 (SHT.1) which show typical sealing details of penetrations.

Also in your November 12, 1982, letter you referenced our telephone conversation of November 4, 1982, in which we requested to provide supplemental information concerning fire door 259. That information is provided as follows.

Fire door 259 does have conduit penetrating the door frame. Those penetrations have been sealed, and final inspection of the seals was performed on July 27, 1982.

Very truly yours, 4E4 ohn R. Marshall Manager, Licensing JRM: LVP: s1 Attachments

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