ML19338G442
| ML19338G442 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 10/02/1980 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19338G441 | List: |
| References | |
| NUDOCS 8010290364 | |
| Download: ML19338G442 (11) | |
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SATETY EVALUATION OF ACCEPTABLE FIRE PROTECTION ITEMS CALVERT CLIFFS NUCLEAR PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50-317 AND 50-318 3.1.13 EMERGENCY COMMUNICATION In tne Safety Evaluation Report issued September 14, 1979 (SER), is was our concern that a single fire could simultaneously damage both communication systems.
By letter dated June 20, 1980, the licensee stated that a completely new and idependent communication system was being installed.
There.are no common conduits used for this system with the existing systems.
The routing of the new system is through stair towers and sprinklered areas and not common with the existing system; nor is any portion of the system in the Control Room common to both the original sound powered and the standard page/ party system.
Based on our review, we conclude that a single fire would not simultaneously damage the communication systems. We find that the communication system meets Section C.4.3(3) of Appendix A to BTP APCSB 9.5-1 and, therefore, is acceptable.
3.1.14 HYDR 0GEli PIPING In the SER, it was our concern that in the event of the hydrogen piping rupture an explosive concentration of hydrogen could occur in the Auxiliary Building.
By letter dated May 20, 1980, the licensee proposed to install excess flow stop valves to limit hydrogen leakage in case of a rupture in the hydrogen piping.
The licensee provided drawings showing the location where the excess flow stop valves will be installed. We have looked at the drawings and con-
.clude that in the event of a rupture anywhere.in the hydrogen piping, the excess flow stop valves will limit the gas flow so that the leakirfg hydro:en will not result in explosive concentrations (greater than 8'l) in the Auxiiiary Building.
All bypass valves around the excess flow stop valves will be locked in a closed position.
Based on the above, we conclude that the excess flow stop valve will automatically stop the flow of hydrogen to the Auxiliary Building in the event of a piping system rupture and, therefore, is acceptable.
3.2.2!1:
ADEOUACY OF DETECTOR INSTALLATION an:
3.2.2(2?
In the SER, it was our concern that proper consideration be given to such factors as ceiling height and configuration, ventilation air flow rate and pattern, in determining the type, number and location of fire detectors.
By letter dated June 20, 1980, the licensee stated that the layout, spacing and monitoring of the existing system was determined by representatives of the Pyrotonics Company, a comoany with experience in fire protection.
The design organization took into consideration'such factors as ventilation air flow G 010290 jf q
rate and patterns, ceiling height, ceiling configuration, and cable tray and equipment locations in determining the number and location of fire detectors. The type of detector was determined by the burning characteris-tics of the combustibles anticipated in the area.
In addition, the licensee
.provided a certification statenent furnished by a professional fire protection engineer which certifies the design of the proposed fire detection systems.
Further, the licensee verified that the spacing between detectors, and between detectors and walls, is within allowable limits as provided in NFPA 72E.
Based on this information, we conclude that the licensee's method of locating smoke detectors utilizes current state-of-the-art techniques and, therefore, is acceptable.
3.2.5 DRAIN SYSTEM BACKFLOW PROTECTION In the.SER, it was our concern that areas which contain combustible liquids and have a common drainage system with safety related areas could pose a backflow hazard of the combustible liquid from these areas to the safety related areas if the drain piping is clogged immediately downstream of the common junction.
By letter dated June 20, 1980,.the licensee provided a. description of the areas wnich contain combustible liquids and the backflow prevention features of the 1
crainage systems in each area. We have reviewed the licensee's information and conclude that the areas which contain combustible liquids and have a common crainage system with a safety related area are the Charging Pum: Rooms, the ECCS Rooms, the Auxiliary feed Pump Rooms, end the Diesel Generator Rooms.
Each ECCS Room is equipped.with a dedicated sump and pump, including a check valve, so the backflow of combustible liquids between these rooms would not The charging pump cubicles within the Charging Pump Rooms are equipped occur.
with interconnected four inch drains.which discharge to Duplex Sump No. 11.
Two sumps are provided, each is ecuipped with a check valve.
Therefore, the backflow of combustible -liquids could only occur between the charging pump cubicles which by themselves do not contain enough combustible. liquid to present a backflow hazard. The Auxiliary Feedwater Pump Rooms are provided w'ith a sump ano duplex pump equipped with check valves and, therefore, the backflow prevention features are acceptable.
The diesel generator rooms share a common drainage system with no provisions to prevent the backflow of combustible liquids between these rooms if the drainage system was clogged immediately downstre'am of the common junction.
Based on the above, we conclude that the drainage systems for the ECCS Rooms, the Auxilii j Feedwater Pump Rooms, and the Chargin5 ? ump Rooms meet Section D.l(i) of Appendix A to BTP APCSE 9.5-1 and, therefore, are acceptable. Mowever, the drainage system for the diesel generator rooms does not meet Section 0.1(i) cf Appendix-A to STP APCSS 9.5-1 and, theref ore, is unacceptable.
The licensee shoulc provice check valves in the Diesel Generator Room drainage system to prevent the backflow of combustible liquids between these rooms.
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. g-3.2.6 : ELECTRICAL'AND PIPING PENETRATION FIRE RESISTANCE and.
3.2.7 'In the SER, it was our concern that. the' electrical and piping penetration
- fire stops may not be adequate to_ prevent the spread of fire from one fire area to another.
By letter dated May 20, 1980,,the licensee described the fire test procedure and his acceptance criteria and provided the results of the fire test for cable and_ pipe penetration seals.
The results of the. test are. recorded in Southwest Research Institute Final Report dated April 10, 1980, entitled
" Fire Stop Penetration Tests on Fire Protection System, Project No. 03-5980-001".
We have reviewed the licensee's fire test procedure and_results and find that i
acceptable criteria were used to evaluate the performance of the electrical and piping penetration fire stops.
Based on-these tests results, we conclude that the fire stops are acceptable.
i 3.2.8 RADIOLOGICAL CONSE0VENCES OF FIRE In the SER, it was our concern that a fire in areas containing radioactive materials may cause the release of radioactivity to the environment.
By letter dated December 21, 1979, the licensee provided the results of an analysis of the plant features which limit radiological consequences of a fire involving radioactive materials.
i Radioactive materials which are contained within pumps, pipes, tanks, and vessels would not be released during a fire'since the means of material con-finement would not burst during a fire. The-plant radioactive liquid and a
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gaseous-discharge systems are each provided with two valves in series which j
fail closed on loss of electric power or air supply.
In addition, the dis-
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il charge piping fram these systems cohtains not only radiation monitors ~ to close j
the-valves on' a high radiation but also a normally shut isolation valve.
The fire protection provided for the HEPA and charcoal filters was previously 1
- evaluated in Section 4.4.2 of the SER and found acceptable.
Spent resins are stored in casks in the waste disposal area which is shielded for radiation and
- protected by-a sprinkler system.
Wastes are stored in steel drums with fusible link tops or within steel cabinets.
The use.of the fusible link. tops wi.ll prevent the spread of fire into or out of the drum.
Based on our review, we conclude that the lice.1see has provided an acceptable level of fire protection for materials containing radioactivity to meet Section G(4) of Appendix A to BTP_APCSB 9.5-1 and, therefore, is. acceptable.
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EFFECT OF FIRE ON RADIATION MONITORS 3.2.9 In the SER, it-was our concern that in the event of a fire the licensee may lose the capability to monitor radiation levels in the plant.
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By letter dated December 21, 1979, the licensee provided the results of'a study which delineated the. backup systems provided for each type of radiation monitoring system.
Our review concluded that the radiation monitoring systems and the alternate systems were acceptable with the exception of the particulate radiation monitoring system which could fail in the case of a smokey fire.
Our 1
consultant recomended that the licensee develop an alternative particulate
. radiation monitc, ring system that will function in the event of a fire.
4 Our consultant's recommendation that the licensee develop an alternative particulate radiation monitoring system is beyond_the scope of this review.
Our guidelines recomend state-of-the-art radiation monitoring capability which i
is adequate to ensure that before smoke and gases from a fire are released to the environment the radiation level is determined to be within the permissible limits of the. plant. Technical Specification.
Further, the licensee's evaluation of the radiological consequences of a fire shows that it ooses no undue hazard to the public.
Based on our review, we conclude that the licensee's radiation monitoring capability meets the intent of Section D.4(a)-cf Appendix A to BTP APCSB 9.5-1 and, therefore, is acceptable with regard to fire protection.
3.3.1 HALON SYSTEMS BACKUP POWER In the SER, it was our concern that the Hhlon suppression systems could not be actuated in the event of a loss cf power to the systems.
By letter dated October 20, 1978, the licensee stated that the Halon suppression systems are designed and installed.in accordance with NFPA No.12A, which requires that Halon suppression systems be provided with an independent means for emergency manual operation. On this basis, we cor.c.lude that the Halon suppression systems could be manually actuated and, therefore, are acceptable.
3.3.2 EMERGENCY LIGHTING In the SER, it was our concern tnat the licensee did not provide adequate emergency lighting for shutdown operations and access / egress routes"to these areas.
By letter dated November 13, 1979, the licensee provided a description of,the new 5 hour5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> battery units which will replace the existing 14-hour units in a t
number of areas.
Our consultants "eviewed the licensee's proposal and recommended that we accept the ty;e of units.
Further, our consultants 4
recommended that in addition to tne areas where the licensee is installing E-hour units upgrade the existin; lb-hour units to 8-hour units in several safety-related areas.
As a result, the licenses has agreed to provide S-hour-battery units in areas 525, 527, and 122.
In addition, the licensee confirnied that all stairways are trovided with 8-hour units.
Our consultant's.
recomendation to upgrade the lh-hour units to 3-hour units in areas U-1, U-2, and to 328 was based on manual fire fighting considerations.
These areas i
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are not required for safe shutdown operations or access / egress routes and, therefore, we consider the lh-hour units to be adequate.
Based on our consultant's recommendations and the licensee's commitments,
'we conclude that the fixed emergency lighting system meets Section 05(a) of Appendix A to STP APCSB 9.5-1 and, therefore, is acceptable.
3.3.3 FIRE 000R SUPERVISION In the SER, it was our concern that the licensee's supervision of fire doors may be inadequate to assure that the fire doors would be.in the proper position or free of obstructions.
By letter dated April 19, 1979, the licensee stated that some fire doors are electrically supervised and alarmed.
The licensee also confirmed by telephone that all fire foors, which are not electrically supervised, will be inspected daily.
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Based on our review, we conclude that the licensee's supervision of fire doors is adequate to assure that the fire doors are in the proper position and/or free of obstructions and, therefore, is acceptable.
3.3.4 REACTOR COOLANT PUMP OIL COLLECTION' SYSTEM In the SER, it was our concern that the oil collection system was not ad. equate to collect and drain lube oil in the ' event of a leak in the reactor coolant pump lube oil system.
By letter dated November 13, 1979, the licensee proposed to provide an oil spillage protection system for each reactor coolant pump.
These systems will consist of encapsulating devices installed around potential leakage points and will be sized to collect oil from a major ' oil leak.
Piping from the encapsulations will accommodate a major oil leak and will be interconnected to a common drain leading to two oil collection tanks.
The entire oil c'ollection system is to be seismically supported.
Based on our review, we conclude that the proposed oil collection system me,ets Section D.2(a) of Appendix,A to BTP APCSB 9.5-1 and, therefore, is acceptable.
3.3.5 FIRE PUMP SEPARATI05 In the SER,.it was our concern that a sprinkler system would not provide an adequate level of fire protection for the redundant fire pumps which are located in the Fire Pump House.
By letters dated April 19, 1979, and November.13, 1979, the licensee provided design description and drawings of the sprinkler system which protects the Fire Pump House.
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6-Our guidelines recommend that fire pumps be separated by a three-hour fire barrier. However, the licensee has installed a sprinkler system in lieu of
-the barrier. The=1icensee states that the fire pumps are capable of operating with sprinklers' operating ~in the room. The Fire Pump House is limited to the fire water supply function, therefore, a fire disabling both fire pumps would not affect the ability of the plant to achieve safe shutdown. The licensee concludes that.the availability of at least one fire pump is assured without the addition of'a fire barrier.
i It is our opinion that the availability of at least one fire pump is not assured by sprinklers alone since they may not be actuated. However, a fire j
in the Fire Pump House resulting in the loss of both fire pumps would not affect the ability of the plant to achieve safe shutdown.
The addition of a 3-hour barrier will_ not provide substantial additional protection for the health and safety of the public and, therefore, the sprinkler sys'em is acceptable.
3.3.6 FIRE FIGHTING STRATEGIES In the SER, it was our concern that the-fire fighting strategies the licensee had developed for seven areas may not be adequate for all plant areas.
By letter dated November.13, 1979, the licensee stated that fire fighting strategies were being developed for all areas which either contain significant quantities of combustible material or which pose unusual problems for the fire brigade combating a fire in that area, all strategies have been developed.
Based on the licensee's commitment and our review, we conclude that the proposed fire fighting strategies will be sdequate and, therefore, are acceptable with regard to fire protection.
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STAFF REQUIREMENTS TO RESOLVE OPEN ITEMS 3.1.19 FIRE DETECTION IN SAFETY-RELATED AREAS In the Calvert Cliffs Fire Protection Safety Evaluation Report dated September 14, 1979 (SER), the licensee proposed to install appropriate fire detection devices in some additional safety-related areas. We requested the licensee to provide design details of this modification for our evaluation.
By letter dated December 21, 1979, the licensee described their fire /
smoke detection system.
The licensee has taken credit for sprinklers, in combination with appropriate water flow alarms, as providing the required fire detection when installed at the ceilings of rooms to protect both equipment and cables.
A sprinkler system does not provide a level of fire detection which is adequate to meet our guidelines for fire detection in safety-related areas.
A sprinkler system, depending on:the severity of the fire, may not be actuated and, therefore, not detect small or slow growing fires in a timely manner, and, therefore, does not provide the required defense-in-depth.
To meet Section III, Paragraph F of proposed Appendix R to 10 CFR Part 50, the licensee must install automatic fire detection systems in all a eas of the plant that contain safe shutdown or safety-related systems or compc7ents.
3.1.20 UNPROTECTED DOORWAYS In the SER, we requested the licensee to provide UL or FM listed fire doors of appropriate ratings, or an acceptable alternate, to protect the unprotected doorways in fire barriers separating various safety-related plant areas, including the five doorways in the computer rooms which -
currently are provided with nonfire rated bullet-proof doors.
By letter dated December 21, 1979, the licensee proposed to use auto-matic sprinklers on one side of a fire barrier in lieu of rated fire doors.
Where credit is taken for automatic sprinklers in lieu of fire doors, at least one sprinkler head will be located adjacent to and immediately above the doorway to provide a water curtain to prevent ex-tension of the fire. No data was provided to justify the non-fire rated bullet-proof doors.
The use of automatic sprinklers on one side of a fire barrier in lieu of rated fire doors is unacceptable.
The reliability and effectiveness of this form of protection has not been demonstrated.
The licensee has assumed that automatic fire suppression systems will always be actuated; this is not supported by fire data.
To meet Section III, Paragraph M of proposed Appendix R to 10 CFR Part 50, the licensee must install doors, frames, and hardware, that have been tested and approved by a nationally recognized testing laboratory, in all door openings of fire barriers separating the various safety-related plant areas.
In addition, the licensee must demonstrate that the
. i non-fire rated bullet-proof doors, located in the fire doorways of the computer rooms, provide an adequate level of fire protection in lieu of rated fire doors.
3.1.21 MANUAL H0SE COVERAGE In the SER, we requested the licensee to provide the results of the hose reach tests for our evaluation.
By letter dated November 13, 1979, the licensee provided the results of the hose reach tests and the location of the additional hose stations.
There remain seven plant areas which will be beyond the effective range of the proposed or installed hose stations. In all these areas, the licensee has estimated the combustible loading to be 2500 BTU per square foot or less.
The licensee states these low fire loads do not justify extension of the standpipe and hose station system to these areas.
Transient combustibles may be introduced or moved through these seven areas and thereby increase the fire load in these areas.
To meet Section III, Paragraph D of proposed Appendix R to 10 CFR Part 50, the licensee must install standpipe and hose stations so that at least one effective hose stream will be able to reach any location of the plant that contains or could present an exposure fire hazard to safety-related equipment.
3.2.1 FIRE HAZARD ANALYSIS In the SER, we requested the licensee to expand the Fire Hazard Analysis u include the effects of fire on safe shutdown capability.
In those plant areas where the analysis could not demonstrate that safe shutdown capability could be preserved, appropriate modifications would be necessary.
An alternate shutdown system should be provided if the provision of other fire protection caes not give assurance that safe shutdown capability.will survive a fire.
By letters dated December 21, 1979 and December 27, 1979, the licensee provided a description of proposed plant modifications based on a fire hazards analysis; however, the analysis for the containment has not been provided.
We evaluated the information the licensee provided and we informed the licensee that we disagreed with the following assumptions in his analysis:
(1) The licensee assumes that an automatic fire suppression system will always prevent the concurrent loss of redundant divisions of cables 3
or equipment as the results of a single fire, regardless of their separation, arrangement, proximity and nature or geometry of the room.
Fire data have shown that automatic fire suppression systems may not be actuated in the event of a fire and, therefore, do not provide, by themselves the required defense-in-depth.
All areas which contain redundant systems required for safe shutdown should be provided with automatic sprinkler systems and early warning detection systems.
Further, in those areas in which the separation of the redundant
systems is less than 20 feet of clear air space, a 1-hour fire rated barrier should enclose one entire division.
Some systems or areas will require additional fire protection, e.g., auxiliary feedwater system.
(2) The licensee assumes that automatic fire suppression systems have 100% reliability.
As stated in Item 3.1.19, a sprinkler system does not provide a level of fire detection which is adequate to meet our guidelines for fire detection in safety related areas.
A sprinkler system, depending on the severity of the fire, may not be actuated and, therefore, not detect small or slow growing fires in a timely manner to provide the required defense-in-depth.
~(3) The licensee assumes thct automatic sprinklers on one side of a fire barrier at doorways are equivalent to a fire door in the doorway. As stated in Item 3.1.20, the use of automatic sprinklers on one side 3
of a fire barrier in lieu of fire rated docrs is unacceptable.
The reliability and effectiveness of this form of protection has not been 1
demonstrated.
The licensee has assumed that automatic fire suppression systems will always be actuated; this is not supported by fire data.
The licensee has nct demonstrated that cables and eouipment of redundant systems..important to achiev.ing safe shutdown conditions to ensure that at least one means of achieving such conditions survives postulated fires.
To meet our fire protection guidelines, we informed the 'icensee that alternate shutdown capability should be provided when saie shutdown cannot be ensured by barriers and detection and suppression systems to ause of the exposure of redundant safe shutdown ecuipment, cabling, cr components in a single fire area to an exposure fire, fire suppression activities or rupture or inadver:en operation of fire suppression systems.
he informed the licensee that su:h a'iternate shutdown capability which is independent of several. fire areas should be provided.
By letter dated Jane 20, 1980, the licensee informed us that our requirements were being evaluated.
To meet Section III, Paragraph G of proposed Appendix R to'10 CFR Part 50, the licensee should provide alternate shutdown capability for the following areas of the plant:
'1)
Tne control room l
'1; Twc cable spreading rooms with adjoining cable chases (1C &2C).
'3)
Six cable chases (1A, IE, 2A, 2B, Horizontal U1, U2),
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2; Other plant areas where redundar.t cabling / equipment required for safe shutdown cannot be separated by fire barriers of appropriate rating, including but not limited to the following:
(a) Auxiliary building corridor and adjoining areas, elevation
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Auxiliary building corridor anc adjoin' ng areas, elevation i
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r (c) Component cooling water pump rooms.
(d) Leach service water pump room.
The alternate shutdown system should meet the requirements of Section i
III, Paragraph L of proposed Appendix R to 10 CFR Part'50.
3.2.2(3)
ADEQUACY OF DETECTOR' INSTALLATION n
By letter dated May 19, 1980, we requested the licensee to provide a
' fixed automatic or manually operated water spray system per NFPA 15 to protect cables in cable chases IC-and 2C.
By letter dated June 20, 1980, the licensee proposed to install an cutomatic total flooding Halon 1301 system to protect cable chases-1C and 2C.
The automatic detection for the system will.consistaof fixed temperature detectors and multipl; " product of combustion" type detectors installed at two elevations.
The licensee states that if the early warning " products of combustion" type detectors do not' respond to a slow developing fire, the fixed temperature detector will actuate the Halon 1301 fire suppression system.
The ability of Halon 1301' fire suppression systems to effectively i
extinguish deep seated cable fires has not been demonstrated.
.Therefore, we find that Halon fire suppression systems are not adequate to protect large concentrations of cables.
4 To meet Section D.3(c) and E.3(c) of Appendix A to BTP APCSB 9.5-1, the licensee must install a fixed water fire suppression system that L
co-forms to the requirements of UFPA 15 to protect cables in cable chases IC and 2C.
1 3.2.4 VENTILATION DUCT PENETRATIONS i
19, 1980, we requested the licensee to verify that By letter dated May the proposed method of fire damper installation conforms to the conditions of listing of the fire damper by the testing laboratory.
By letter dated June 20, 1980, the licensee responded that they will verify that the method of fire damper installation conforms to-the conditions off listing of the fire damper by the testing laboratory and the installatico t
l provides the required fire resistance to meet the Fire Hazard Analysis.
A report of the-licensee s findings will be provided to us at a later date.
To meet Section 0.1(j) of Appendix A to BTP APCSS 9.5-1f and Section III, Paragraph M of proposed Appendix R to 10 CFR Part 50, the licensee must protect all fire barrier openings for ventilation. systems with an approved fire damper. having a fire rating equivalent to that required of the barrier.
Further,-the method of installation of the fire damper should
. conform to the condition of the listing of the fire damper by the testing laboratory.
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. 3.2.5 DRAIN SYSTEM BACKFLOW PROTECTION In the SER, it was our concern that the backflow.of combustible liquid could occur between the Diesel Generator Rooms.
By letter dated June 20, 1980, the licensee responded that the Diesel Generator Room floor drains are located more than four feet.below the finished floors so that before backflow can occur liquid levels in adjacent rooms must reach significant depths.
Further, the Diesel Generator Rooms are at the same elevation and the licensee concludes that before backflow would occur the liquid would flow through door openings to the yard.
Each Diesel Generator Room contains over 1000 gallons of combustible liquids.
If the drainage system shared by these rooms was clogged immediately downstream of the common junction the backflow of combus-tible liquid between the rooms may occur.
To meet Section D.1(i).of Appendix A to BTP APCSB 9.5-1, the licensee must install check valves to prevent the backflow of combustible liquids letween these rooms.
3.3.7 QUALITY ASSURANCE PROGRAM in the SER, we requested that the licensee provide a comparison of their Quality Assurance Program for fire protection with our guidelines.
By letter dated December 31, 1979, the licensee proviced' a list of the exceptions where their fire protection QAP is not identi. cal to our guidelines.
The licensee's response does not describe in sufficient detail how the ten specific quality. assurance criteria in Section C of Appendix A to BTP ADCSB 9.5-1 will be satisfied.
To meet Section C of Appendix A to STP APCSB 9.5-1, the licensee must have their QA program for fire protection under the management control of the QA organization.
This control consists of (1) formulating and/or verifying that the fire protection QA program incorporates suitable requirements and is acceptable to the management responsible for fire protection and (2) verify the effectiveness of the QA program fer fire protectica through review, surveillance, and audits.
Performance of other QA program functions for meeting the fire protection requirements may be performed by personnel outside of the QA organization.
The QA program for fire protection should be part of the overall plant QA program.
These QA criteria apply to those items within the scope of the fire pro-tection program, such as fire prctection systems, emergency lighting, communication and emergency bredthing apparatus as well as the fire pro-l tection requirements of applicable safety-related equipment.
In addition, the licensee must apply the same controls to each criterion of Section C which are com'ensurate with the controls cescribed in their m
l operational QA program.
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