ML20133J015
| ML20133J015 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/14/1985 |
| From: | Bailey J GEORGIA POWER CO. |
| To: | Adensam E Office of Nuclear Reactor Regulation |
| References | |
| GN-718, NUDOCS 8510180228 | |
| Download: ML20133J015 (2) | |
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Georgia Power Company Post Office Box 4545 Atlanta, Georgia 30302 Vogtle Project Telephone 404 522-6060 Southem Cormany Services, ins:
Post Office Box 2625 Bermengham, Alabama 35202 Tekaphone 205 870-60n October 14, 1985 3
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Director of Nuclear Reactor Regulation File: X6BB06 Attention: Ms Elinor G. Adensam, Chief Log: GN-718 Licensing Branch #4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C.
20555 NRC DOCKET NUMBERS 50-424 AND 50-425 CONSTRUCTION PERMIT NUMBERS CPPR 108 AND CPPR-109 V0GTLE ELECTRIC GENERATING PLANT-UNITS 1 AND 2 CONTROL ROOM CABINET SM0KE DETECTION
Dear Mr. Denton:
Branch Technical Position (BTP) CMEB 9.5-1 Section C.7.b states that smoke detectors should be provided in the control room, cabinets, and consoles. Fire detection capability for the VEGP control rocm is provided by a combination of in panel detectors and ceiling mounted area detectors.
Fire detection for the control room consoles and cabinets, other than the main control board, is provided by more than 40 ceiling mounted ionization type smoke detectors per unit distributed throughout the control room and the immediate peripheral areas. These ceiling mounted detectors were located in accordance with National Fire Protection Association (NFPA) Code 72E with consideration given to the location of HVAC supply and return registers and expected air currents within the control room.
ihe HVAC system has been designed to provide thorough mixing of the control room air. Slot type diffusers have been installed in the main control board area to further promote mixing. This design, together with the well-distributed network of smoke detectors, ensures prompt fire detection regardlesc of its point of origin. The mixing of the
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air also increases the likelihood of smoke detection by control room personnel.
The control room is manned on a continuous basis.
Fire detection for the main control board will be provided by ionization type smoke detectors installed near the top of each section of the main control board. These detectors will augment the ceiling mounted detectors and provide additional assurance of early fire detection of potential fires in the main control board.
$8 e
0510180228 851014
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PDR-ADOCK 05000424 F
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a Director of Nuclear Reactor Regulation October 14, 1985 Page 2 Seven of the 54 cabinets in the control room complex contain more than one train of redundant safe shutdown equipment. Within these cabinets, redundant trains have been separated so that a small fire in a single cabinet is not likely to disable both trains. This separation is a minimum of 6 inches with no barrier, or if less than 6 inches a sheet metal barrier or metal conduit is provided as specified in IEEE 384-74 as endorsed by Regulatory Guide 1.75.
If the fire does spread to redundant trains or makes the control room uninhabitable, alternate shutdown panels are located outside the main control room fire area to provide remote shutdown capability. Evacuation to the alternate shutdown panel requires no operator action in the control room prior to the evacuation, and complete electrical isolation between the control room and the alternate shutdown panels is accomplished through transfer switches.
The fire detection design for the VEGP control room provides early warning of a fire in the control room and is therefore an acceptable deviation from the requirements of CMEB 9.5-1, section C.7.b.
If your staff requires any additional information, please do not hesitate to contact me.
Sincerely,
.z' s.
J. A. Bailey JAB /RLK/caa xc:
D. O. Foster R. A. Thomas J. E. Joiner, Esquire B. W. Churchill, Esquire M. A. Miller (2)
B. Jones L. T. Gucwa G. Bockhold, Jr.
T. Johnson D. C. Teper L. Fowler W. C. Ramsey Vogtle Project File 0175V