ML20141F635
| ML20141F635 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 05/16/1997 |
| From: | Duffy J VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| BVY-97-62, NUDOCS 9705210392 | |
| Download: ML20141F635 (2) | |
Text
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VERMONT YANKEE ENUCLEAR POWER CORPORATION t
Ferry Road, Brattleboro, VT 05301-7002 ENGINEERING OFFICE N '-
580 MAIN STRE.ET BOLToN. MA 01740 s
(508) 779-6711 May 16,1997 l
BW 97-62 United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
. References; (a) License No. DPR-28 (Docket No. 50-271)
(b) Letter, WNPC to USNRC, BVY 97-9, dated January 15,1997 (c) Letter, VYNPC to USNRC, BW 96-43, dated April 4,1996 (d) Letter, VYNPC to USNRC, BW 96-67., dated May 21,1996 (e) Smoke Detectors for Fire Protective Signaling Systems, Standard for Safety, U. L.
268. September 19,1983 (f) Fire Protection and Fire Fighting in Nuclear installations, International Atomic Energy Agency,1989
Subject:
Additional Information Regarding Fire Detection Installation at Vermont Yankee Nuclear Power Station in Reference (b) Vermont Yankee provided additional information requested by the NRC regarding
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- exemption requests submitted by Vermont Yankee in References (c) and (d). In Reference (b)
Vermont Yankee stated " Vermont Yankee plans to install additional ceiling level smoke detection in the open area of Fire Zone RB-4, the ante room, the steam tunnel and the railroad airlock to meet the spacing requirements and location criteria of the edition of NFPA 72 in effect at the time of the design."
\\'g Since submitting Reference (b), Vermont Yankee has determined that use of smoke detectors for fire detection in the steam tunnel is inappropriate because of the normal environmental conditions
~ in the steam tunnel. Smoke detectors are required to be Underwriter Laboratory (U.L.) listed per h'
NFPA 72. Smoke detectors, including projected beam type, sampling type, and spot type are tested at normal operating ranges between 32*F and 120 F in accordance with U.L. Standard 268
[ Reference (e)). Reliability of smoke detectors in environments above this temperature are not tested, and therefore' detector operability may be affected. In addition, smoke detectors become less sensitive in environments with high radiation fields [ Reference (f)].
r Attemative methods of fire detection were reviewed that comply with the spacing requirements and i
location criteria of NFPA 72. Maintenance of the detection system was also considered, as accoss
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to the steam tunnel is restricted during normal plant operation.
9705210392 970516 PDR ADOCK 05000271
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O VERMONT YANKEE NUCLEAR POWER CORPORATION Unitdd States Nuclear Regulatory Commission May 16,1997 Page 2 of 2 As a result of this review, Vermont Yankee has determined that linear heat detection is the most appropriate method of fire detection for the steam tunnel. Linear heat detection is a cable that detects heat anywhere along its length. The sensor cable is constructed of two (2) 18 AWG steel conductors individually insulated with heat sensitive polymer. The insulated conductors are twisted together to impose a spring pressure between them, then wrapped with a protective tape and finished with an outer jacket suitable for the environment in which the detector will be installed.
The linear heat detection method is compatible with other initiation devices on the same circuit.
Linear heat detection is presently in use at nuclear power generation companies such as Georgia Power Company, Virginia Electric and Power Company, Baltimore Gas & Electric Company and Seabrook Station. The Protectowire Co., Inc. is the manufacturer of the linear heat detection to be used in the steam tunnel. Vermont Yankee believes this type of detection satisfies the fire detection requirements of 10CFR50, Appendix R, section Ill.G.3 and is therefore acceptable for this application.
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We trust that this submittal provides adequate information. However, should you have questions or require additional information, please contact this office.
Sincerely, VERMONT YANKEE NUCLEAR POVER CORPORATION 6WMMf James J. Duffy l
Licensing Engineer l
l c: USN.RC Region i Administrator USNRC Project Manager - VYNPS USNRC Resident inspector - VYNPS I
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