ML20137K454
| ML20137K454 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 01/16/1986 |
| From: | Bailey J GEORGIA POWER CO. |
| To: | Adensam E, Denton Office of Nuclear Reactor Regulation |
| References | |
| GN-781, NUDOCS 8601240092 | |
| Download: ML20137K454 (8) | |
Text
Georgia Power Company Project Mmagement
- Rout 2 2. Box 299A Waynesboro. Georgia 30830 Telephone 404 724-8114 404 554 9961 e
Southem Company Services. Inc.
Post Office Box 2625 Birmingham. Alabama 35202 VOgde PMW Telephone 205 870-6011 January 16, 1986 Director of Nuclear Reactor Regulation File: X6BB06 Attention: Ms. Elinor G. Adensam, Chief Log:
GN-781 Licensing Branch #4 Division of Licensing U.S. Nuclear Regulatory Con:nission 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 SER OPEN ITEM 7A: FIRE DOORS AND FIRE DAMPERS
Dear Mr. Denton:
Enclosed for your staff's review is additional information related to the unrated hatch covers and oversized fire dampers installed at Plant Vogtle.
The safe shutdown analysis has allowed combination of fire areas and therefore the number of unrated hatches and overeized fire dampers installed in fire l
area boundaries. The enclosure provides additional justification for the VEGP f
request for deviation from the CMEB 9.5-1 requirement to install 3-hour fire-rated fire doors and fire dampers in fire area boundaries.
If your staff requires any additional information, please do not hesitate to contact me.
Sincerely,
.h.
J. A. Bailey Project Licensing Manager JAB /rlk/caa Enclosure xc:
D. O. Foster G. Bockhold, Jr.
R. A. Thomas T. Johnson (w/o enclosure)
J. E. Joiner, Esquire D. C. Teper (w/o enclosure)
B. W. Churchill, Esquire L. Fowler M. A. Miller (2)
W. C. Ramsey B. Jones (w/o enclosure)
Vogtle Project File L. T. Gucwa 0
-'O1240092 24
%g ADOCA PM E
e
ATTACHMENT 1 Open Item:
7A Fire Doors and Fire Dampers SER Section:
9.5.1.4 Building Design VEGP Unrated Hatch Covers in Fire Area Boundaries Nine (9) of the original ten (10) unrated hatch covers are no longer located in fire area boundary barriers. As such, there is now only one (1) unrated hatch cover installed in a 3-hour fire area boundary barrier. This hatch cover is located at level A of the auxiliary building wing area and separates the train B component cooling water pump room (fire zone 37) from the level B (fire zone 26A) corridor area just east of the auxiliary cooling water and safety injection pump rooms. The level B corridor contains Train A safe shutdown raceway.
The hatch opening is used to facilitate equipment maintenance by allowing transporting of large components to and from the plant shop areas.
Permanent closure of the opening cannot be tolerated from a maintenance standpoint and replacement or modification of the opening so as to obtain a rated closure is not warranted based on the low level of combustibles and the distance separating redundant safe shutdown trains.
The hatch opening is 7' x 12' and while the 1/4-inch thick A36 steel checkered plate hatch cover is not rated or designed as a fire barrier, it does represent a physical barrier and an impediment to fire propagation from one level of the auxiliary building to the other. The rest of the floor area separating the train B equipment area at level A from level B is rated as a three hour fire barrier.
Train A safe shutdown components (includes electrical raceway) are located at least 30 horizontal feet from thy underside (level B) of the hatch opening.
Train B safe shutdown components.(includes electrical raceway) are located at least 5 horizontal feet from the* hatch opening (16' at level A, 12' at level 1 and 5' at level 2),
The aggrega(e separation distance between redundant safe shutdown trains is at least 35 h;rizontal feet.
y There are no combustible materials directly below or above the hatch as these areas are saintained free of obstruction to facilitate equipment moving.
There are no intervening combustibles between the hatch opening and the train B safe shutdown components located above the unrated hatch. The only combustible which represents an intervening combustible of significance below the hatch opening is a single cable tray which is at least 15 horizontal feet from the underside of the hatch opening at level B.
)
s C217V
Fire Doors and Fire Dampers (Cont'd)
Page 2 A fire detection system is provided in the area on both sides of this un nred hatch.
In addition, an automatic preaction sprinkler system is provided in the fire zones immediately above and below this unrated hatch.
The results of the fire hazards analysis as tabulated below, in addition to the above, is used to justify this deviation. The fire hazards values presented below are based upon current design and should not vary significantly. Finalized values will be presented in an upcoming FSAR amendment.
Unrated Hatch Cover, Auxiliary Building Level A, Wing Area:
Size, ft.
7 x 12 Fire Area Separation 1-AB-LD-G & 1-AB-LA-B Fire Zone Separation 26A & 37 Fire Hazards Fire Zone 26A Fire Zone 37 Fire Load, ib.
4,816 8,199 (Cable insulation)
Combustible Loading, Btu /ft2 26,057 34,684 Fire Severity, min.
19.5 26.0 VEGP Oversize Fire Dampers in Fire Area Boundaries:
Eleven of the original 17 oversize fire dampers are not located in fire area boundary walls. As such, there are now only six (6) fire damper assemblies (3 each in units 1 and 2) installed (2 vertically and 4 horizontally) in 3-hour fire area boundary barriers which should comply with the guidelines of BTP CMEB 9.5-1.
These fire dampers do not bear a UL label of approval as their size exceeds the manufacturer's UL test limitations.
The manufacturer's "as-tested" configuration limits the size of a single fire damper in multiple damper assemblies to 36" x 36".
VEGP oversize fire dampers comply with the single damper in multiple damper assembly size limitations.
However, the VEGP oversize fire dampers do not comply with the overall damper assembly size requirements which is limited to 36" x 72" when installed in a horizontal configuration and to 72" x 72" when installed in a vertical configuration.
(Note that 2" wide mullion is provided between single fire dampers in multiple damper assemblies.)
0217V
4 Fire Doors and Fire Dampers (Cont'd)
Page 3 VEGP fire area boundaries have been established in accordance with the guidance of BTP CMEB 9.5-1, Section B.3, " Establishment and Use of Fire Areas" in that separation of redundant safety divisions, separation of safety-related systems from fire hazards in nonsafety-related areas and isolation to limit the spread of fires between components that are major fire hazards within a safety division have been considered as well as separation of redundant safe shutdown trains.
In spite of the fact that the oversize fire damper assemblies are without a UL label of approval, the manufacturer has certified that the fire dampero have been fabricated of the same material, with the same method, and to the same design and UL procedures as their standard UL approved 3-hour multiple fire i
dampir assembly. These oversize fire damper assemblies have been evaluated I
I and found to be acceptable by a registered fire protection engineer.
1 l
The results of the fire hazards analysis as tabulated below, in addition to the above, is used to justify this deviation. The fire hazards values presented below are based upon current design and should not vary significantly. Finalized values will be presented in an upcoming FSAR amendment.
I I
Results of Unit 1 Analysis t
j A.
Unrated Fire Damper A-1551-S7-612 Auxiliary Building 4
i Size, in.
94 x 48 Installation Configuration Vertical Number / Size of Single Dampers 6/30 x 23 Fire Area Separation 1-AB-L2-A & 1-AB-L1-B Fire Zone Separation 53 & 149 Fire Hazards Fire Zone 53 Fire Zone 149 Fire Load, lb.
Cable Insulation 10,123 2,864 Charcoal 32,700 0
Combustible Loading, Btu /f t2 78,354 57,149 Fire Severity, min.
58.8 42.9 j
0217V
i Fire Doors and Fire Dampers (Cont'd)
Page 4 The following design features are additional bases for acceptability regarding this specific damper.
1.
Each fire area has been provided with an early warning fire detection system.
2.
Fire area 1-AB-L1-B is equipped with partial area automatic sprinkler protection in fire zone 149 in the immediate vicinity of the oversize fire damper.
3.
Fire area 1-AB-L2-A (fire zone 53) is equipped with partial area automatic sprinkler protection.
4.
The charcoal filtration units in fire area 1-AB-L2-A are provided with an integral water deluge system.
4 5.
Fire area 1-AB-L1-B contains Train B safe shutdown electrical distribution equipment and cables. Fire area
.'.-AB-L2-A contains Train A safe shutdown cables and the 1
Train B safe shutdown room cooler that serves fire area 1-AB-L1-d.
Fire area 1-AB-L1-B is relatively small and therefore little horizontal separation distance is available between the oversize fire damper and the Train B shutdown components. However, fire area 1-AB-L2-A is relatively large. The Train B safe shutdown room cooler that serses fire area 1-AB-L1-B is just outside the fire area beundary. The Train A safe shutdown electrical cables are located approximately 75 horizontal feet from the oversize damper and the Train B room cooler unit. The partial area coverage automatic preaction fire suppression system in fire area 1-AB-L2-A protects the intervening separation distance.
B.
Unrated Fire Damper 1-1551-S7-626 Size, in.
64 x 54 Installation Configuration Horizontal Number / Size of Single Dampers 4/31 x 26 Fire Area Separation 1-AB-L1-B & 1-AB-LD-B Fire Zone Separation 149 & 46 Fire Hazards Fire Zone 149 Fire Zone 46 Fire Load, ib.
Cable Insulation 2,864 17,281 Charcoal 0
0 Combustible Loading, Btu /ft2 57,147-27,284 Fire Severity, min.
42.9 20.5
Fire Doors and Fire Dampers (Cont'd)
Page 5 The following design features are additional bases for acceptability regarding this specific damper:
1.
Each fire area has been provided with an early warning fire detection system.
2.
Fire area 1-AB-L1-B is equipped with partial area automatic sprinkler protection in fire zone 149 directly over the fire damper.
3.
Fire area 1-AB-L1-B contains Train B safe shutdown electrical distribution equipment and cables. Fire area 1-AB-L1-B is relatively small and therefore little horizontal separation distance is available between the oversize fire damper and the Train B safe shutdown components. Fire area 1-AB-LD-B is a very large fire area encompassing many levels in the central part of the auxiliary building. At level 1 (fire zone 46) of fire area 1-AB-LD-B just below the oversize fire damper, there are no safe shutdown equipment or cables. There are no cable trays or other combustible materials of significance at level 1 of fire area 1-AB-LD-B in the immediate vicinity of the oversize fire damper.
C.
Unrated Fire Damper A-1551-S7-523 Size, in.
52 x 44 Installation Configuration Horizon tal Number / Size of Single Dampers 4/25 x 21 Fire Area Separation 1-AB-LD-B & 1-AB-LD-A Fire Zone Separation 46 & 11B Fire Hazards Fire Zone 46 Fire Zone llB Fire Load, Ib.
Cable Insulation 17,281 42,352 Charcoal 0
0 Combustible Loading, Btu /ft2 27,284 173,011 Fire Severity, min.
20.5 133.5 0217V
Fire Doors and Fir e Dampers (Cont'd)
I Page 6 The. following design features are additional bases for acceptability regarding this specific damper:
1.
Each fire area has been provided with an early warning fire detection system.
2.
Fire area 1-AB-LD-A is equipped with partial automatic sprinkler protection (not in the immediate vicinity of the oversize fire damper).
3.
Fire area 1-AB-L1-B is a very large fire area encompassing many levels in the central part,of the auxiliary building.
At level 1 (fire zone 46) of fire area 1-AB-LD-B just above the oversize fire damper, there are no safe shutdown equipment or cables.
Fire area 1-AB-LD-A (fire zone llB) also encompasses many levels in the eastern part of the central section of the auxiliary building. Fire area 1-AB-LD-A contains predominantly Train B safe shutdown residual heat removal system equipment and Train B safe shutdown electrical cables. Very little horizontal j
separation distance is available between the oversize fire damper and the Train B safe shutdown components. However, a major radiation shield wall with a labyrinth entrance is located between the oversize fire damper and the portion of fire area 1-AB-LD-A containing the safe shutdown equipment. There are no cable trays or other combustible materials of significance at level 1 of fire area 1-AB-LD-B in the immediate vicinity of the oversize fire damper.
1 4
4 0217V
o o:
l I have evaluated.the following oversize
- fire dampers installed at Plant Vogtle:
[
Tag No.
Size l
1.
A-1551-57-612 94x48 Vertical 2.
A-1553-57-403 48x96 Vertical 3.
A-1553-S7-602 48x96 vertical 4.
1-1551-S7-626 64x54 Borizontal 5.
A-1551-57-523 52x44 Borisontal 6.
2-1551-57-626 64x54 Borisontal 7.
A-1551-57-524 52x44 Borisontal 8.
A-1553-57-607 48x86 vertical 9.
A-1553-S7 608 48x86 Vertical
- 10. A-1551-57-613 80x48 Vertical Based upon the review of Air Balance, Incorporated certification of materials and construction letter of February 24, 1982; UL File R4708-Project 80NK10529 December 1,1980, " Report on Vertically Mounted Fire Dampers of the Curtain Type for Three Hour Classification"; UL File R4708-8-Assignment 690R3968 July 9,1969, " Report on Horisontally Mounted Fire Dampers of the Curtain and Round Single Blade Types for 1-1/2 Hour Classification"; my discussions with Dennis Kubicki, NRC; the VEGP blue prints and specifications; as well as a review of NFPA 90A, and UL Standard 555; and various conversations with the UL damper committee, it is my opinion that the above fire dampers meet, to an engineering certainty, the standards of UL 555 and NFPA 90A and will function in the necessary manner as three hour fire barriers.
1 f
A-W L. C. Barbe Registered Fire Protection Engineer, California #435
- Fire damper size limited to 72x36 for horisontal applications and 72x72 for vertical applications by UL test.
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