ML18004A500
| ML18004A500 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 08/25/1986 |
| From: | Zimmerman S CAROLINA POWER & LIGHT CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NLS-86-309, NUDOCS 8609020122 | |
| Download: ML18004A500 (47) | |
Text
RE('UL,, QR Y INFORMATION D I STR I BUT I SYSTEM ( R I DS >
~l
.ACCESSION NBR: 8609020122 DOC. DATE: 86/08/25 NOTARIZED: NO DOC)(ET 0 FAC IL: 50-400 Sh earon Harris Nuclear Power Plant> Unit 1> Car o l ina 05000400 AUTH NAME AUTHOR AFFILIATIO'4 I ZIMMERMAN>S. R. Carolina Poeer Zc Light Co.
RECIP. NAME RECIPIENT AFFILIATION DENTON> H. R Qf f i ce of Nuc lear Reac tor Regul ati on. Direc tor (p ost 851125
SUBJECT:
Forwards analyses h discussions intended to resolve control room habitability following postulated chlorine release accident 3ssue. Marked up FSAR pages. reflecting analysis as-designed parameters. also enc l.
DISTRIBUTION CODE: 9001D COPIES RECEIVED: LTR ENCL SI ZE:
TITLE: Licensing Submittal: PSAR/FSAR Amdts 8r Related Correspondence NOTES: Application For permit reneual f iled. 05000400 RECIPIENT COPIES REC IP I ENT COPIES ID CODE/NAME LTTR ENCL I'D CODE/NAME LTTR ENCL PWR-A EB 1 1 PWR-A EICSB 2 2 PWR-A FOB 1 1 PWR-A PD2 LA 1 PWR-A PD2 PD 1 BUCKLEY> 9 Oi 2 PWR-A PSB 1 1 PWR-A RSB 1 1 INTERNAL: ADM/LFMB 0 ELD/HDSi 1 0 IE FILE 1 1 IE/DEPER/EPB 36 1 1 IE/DGAVT/GAB 21 1 NRR BWR ADTS 1 0 NRR PWR-9 ADTS 0 NR >M. L 1 1 NRR/DHFT/MTB 1 04 1 1 R(:N2 3 3 RM/DDAMI /M I 9 1 0 EXTERNAL: BNL(AMDTS ONLY> 1 DMB/DSS (AMDTS) 1 LPDR 03 1 NRC PDR 02 1, NSIC 05 1 1 PNL CRUEL> R 1 1 TOTAl NUMBER OF COPIES REQUIRED: LTTR 30 ENCL 25
1 L
Carolina Power 8 Light Company SERIAL: NLS-86-309 AUG 4S 1986 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation United States Nuclear Regulatory Commission Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT NO. 1 - DOCKET NO.50-000 A SUPPLEMENTARY ANALYSIS OF CONTROL ROOM HABITABILITY FOLLOWING A POSTULATED CHLORINE RELEASE ACCIDENT
Dear Mr. Denton:
As requested by the NRC, Carolina Power R Light Company (CPRL) has performed a supplementary analysis of the habitability of the Shearon Harris Nuclear Power Plant (SHNPP) control room following a postulated rupture of the railroad tank car that serves as the on-site chlorine storage tank. A recently performed habitability analysis showed that this postulated design-basis accident did not pose a hazard under selected 95 percentile meteorological conditions. That analysis assumed that the control room was habitable as long as the chlorine concentration inside did not exceed the NIOSH/OSHA IDLH Tevel of 25 ppm. The NRC Staff, however, asked to see the results of an analysis employing 15 ppm as a maximum acceptable concentration. Although we had per formed an analysis using that concentration, the Staff was concerned that the report of that study did not explicitly show results for stability classes A C, and wished formal documentation for our assertion that under these unstable atmospheric conditions, a postulated accident could not pose a hazard.
Another question raised by the Staff reviewer for SHNPP concerned the original methodology described in NUREG-0570 for calculating the initial radius of the puff of chlorine that is emitted immediately after the rupture of the storage tank. That methodology, embodied in the TOXCHM computer program which was used for these studies, assumes the puff to have a vapor density corresponding to the temperature of the ambient air. However, the puff would in fact be cooled by the process of vaporization that creates the puff. To demonstrate the effect that this cooling could have on our results, an additional analysis was performed for one meteorological case which employed a vapor density for chlorine corresponding to a lower temperature.
Attachment 1 presents analyses and discussions which are intended to resolve these issues. Also attached (as Attachment 2) are marked-up FSAR pages that reflect this analysis and reflect the as-designed parameters associated with the Harris Control Room. These markups will be incorporated in a future (post-fuel load) amendment to the FSAR. If you have any questions on this subject, please contact Mr. D. C. McCarthy at (919) 362-2010 or (919) 836-7715.
Yours very truly, 860'F020122 860825 PDR ADQCK 05000400 S~~~~
PDR . Zi erman ger Nuclear Licensing Section DCM/crs (00533DK)
Attachments cc: Mr. B. C. Buckley (NRC)
Mr. G. F. Maxwell (NRC-SHNPP)
Dr. 3. Nelson Grace (NRC-RII) 411 Fayetteville Street ~ P. O. Box 1551 o Raleigh, N. C. 27602 8o~l
0 3,'lj " P ff Jlky
ATTACHMENT 1 to NLS-86-309
- 1. METHODOLOGY 1.1 Re-analysis. of On-site Tank Rupture An analysis has been performed of the catastrophic sudden failure of the on-site storage tank under all 24 combinations of windspeed and stability class for the ENE sector that are listed in Table 2.3.3-13 of the SHNPP FSAR. Accidents occurring during stability classes E G are assumed to occur at night, since these classes do not commonly occur in the daytime.
Therefore, the maximum likely nighttime temperature of 86'F was assumed (higher temperatures result in greater flash fractions and evaporation rates and are, thus, conservative). Classes A D may occur in the daytime, so the highest likely temperatures that occur at the SHNPP site were used: 104'F for the ambient air temperature and 122'F for the ground. The chlorine toxicity limit was assumed to be 15 ppm, following the guidance of RG 1.78.
1.2 Effect of Puff Cooling 1.2.1 Meteorological Parameters To demonstrate the effect of a lowered temperature of the initial chlorine puff on the calculated .time before the chlorine concentration in the control room reaches the toxic limit, the analysis has been repeated under one set of meteorological conditions'stability class G and a windspeed of 5.5 mph. Any further contraction of the compact puff modeled for this stability class would have a more pronounced effect than on the more diffuse puffs of the lower stability classes, since the overall sigma is calculated as the root mean square of the sigma due to atmospheric dispersion and that due to the initial puff size. The highest windspeed range corresponding to this stability class produces the shortest time to toxicity, so that any decrease would be more pronounced than for cases where the time was longer.
1.2.2 Vapor Density Calculation The TOXCHM program calculates the fraction of chlorine that is suddenly vaporized by the following equation:
f(T H Tb)C f flash fraction Ta ambient air temperature Tb boiling point of chlorine C specific heat of liquid under constant pressure H heat of vaporization This equation conservatively overestimates the flash fraction, since it assumes that the heat available for vaporization is the difference of the heat content of the initial mass of chlorine at the ambient temperature and its heat content at the boiling point. In fact, the available heat is less because the puff is at a temperature intermediate between the boiling point and ambient. Employing similar reasoning, the analysis assumes that the (4053JDK/crs )
temperature of the puff will be the average of the ambient ax,r temperature and the boiling point, the warming effect of the entrained air being neglected.
Since the boiling point of chlorine is -34.6'C and the air temperature is assumed to be 30'C in the case being considered, we obtain an average puff temperature of -2.3'C. The vapor density of chlorine at 0 'C is listed in the CRC Handbook of Chemistry and Physics. Applying the ideal gas law.'
D =D T
T
= density of vapor at temperature T 3.241 g/1 (T = 270.9 K = -2.3'C)
D = density of vapor at temperature T 3.214 g/1 (T = 273.2 K = O'C)
- 2. RESULTS 2.1 On-site Tank Rupture The results of the analysis of the postulated rupture of the on-site storage tank under all 24 combinations of windspeed and stability class are shown in the following table. The vapor density of chlorine was taken from the original TOXCHM model.
Stability Wind Speed Frequency Time of Toxicity Case Class (mph) (x) (min'.sec) 1 G 0.4 7.68 43:55 2 G 2.1 22.00 8:05 3 G 5.5 0.74 3:10 4 F 0.4 0.52 43:20 5 F 2.1 11.89 8:00 6 F 5.5 1.11 3:09 7 E 0.4 0.22 42:20 8 E 2.1 10.93 7:55 9 E 5.5 7.61 3:15 10 E 10.0 1.70 1:50 ll 12 E
D 15-5 0.4 0.07 0.15 1:16 41:00 13 D 2.1 6.13 7:50 14 D 5.5 15.73 3:15 15 D 10.0 2.29 2:00 16 C 2.1 0.44 8:15 17 C 5.5 3.54 3:55 18 C 10.0 0.59 6:20 19 B 2.1 0.30 10'00 20 B 5.5 2.14 rC 21 B 10.0 0.22 22 A 2.1 0.07 21:40 A
23 A 5.5 3.03 24 A 10.0 0.89 Toxicity limit never reached.
(4053JDK/crs )
As can be seen, under stability classes A C (cases 16 24), the earliest time that the toxicity limit is reached is 3 minutes and 55 seconds after the accident. Since the chlorine alert in the control room alarm will be annunciated within 24 seconds of the release, the results of these cases do not increase the overall frequency of occurrence of meteorologicaL conditions under which the postulated accident can pose a hazard to control room personnel. Only for cases 10, ll, and 15 is the warning time less than or equal to 2 minutes. Since those cases have an overall frequency of 4.06 percent, they can be properly excluded from consideration.
2.2 Effect of Puff Cooling Case 3 in the above table was re-analyzed using a vapor density of 3.241 g/L. The time that the toxicity limit was reached was found to be 3 minutes and 10 seconds, the same as in the previous analysis. Thus, for'he purposes of this study, using a more realistic value of the vapor density does not affect the results.
(4053JOK/crs )
ATTACHMENT2 REVISED FSAR PAGES (3962GAS/pgp)
SHNPP FSAR Regulatory Guide 1.95 PROTECTION OF NUCLEAR POWER PLANT CONTROL ROOM OPERATORS AGAINST AN ACCIDENTAL CHLORINE RELEASE (REV 1)
The SHNPP Project complies with the intent of this guide with the followin clarification:
>phon l 4>sauce.
Regulatory Position C.4.d requires t e remote chlorine etectors at the chlorine storage area to e Seismic Category I and Class 1E. Upon evaluation of the SHNPP site, it w d ermi ed that no Seismic Category I/Class lE structure is located between the chlorine storage areas and the closest contr r om axr inta e duct to mount the detectors.
Therefore, the remote chlorine detectors are purchased to Seismic Category I, Class lE requirements and qualified as such; however, the detectors are not mounted in a Seismic Category I structure nor are the interconnection cables routed in Seismic Category I duct banks.
Class lE qualified interconnection cables are provided between the remote detectors at the chlorine storage area and the RAG located chlorine system processor. The routing of the Class 1E qualified cabling in the non-Seismic Category I duct bank will meet the intent of the separation criteria for safety class cabling. Each cable for the redundant remote detectors will be routed in separate conduit with adequate separation between redundant channels, however, the Class 1E qualified cables will be routed along with non-nuclear safety-related cabling.
i The chlorine detector system is designed to preclude any effects from 20 installation o'f Class lE qualified remote detector cabling in a non-Seismic Category I duct bank by providing a Class 1E isolation device between the chlorine detector system processor and the control unit. The chlorine detector system will perform its intended function of control room isolation either upon detection of high chlorine or system malfunction (i.e., fail safe).
=.P add: ~~+~~c Sections 9.4.1 and 6.4.
'8'eferences:
1.8-125 Amendment No. 20
/g~g~- kg 7'AF /s<~7~a >l~ <> <+~i~g~ rO ~=
/PgAp'A'ccFc1 P.R i~li'in>> c/wl'J~gg p&,
/)Bc/6'he control room is assumed to qualify as a Type V for the purpose of determining habitability in case of an on-site chlorine release ~ Under-all credible accident conditions, the remote detectors vill alara and isolate the control room before the chlorine gas can reach the air intake; therefore, the isolation time based on the local detectors is not relevant to an on-site accidental release.
The control room does not qualify for any of the categories in Table 1 of
~/~~ ~y~e~. guide for an off-site chlorine release accident. Site-specific omsI+ Wuc(
analyses of the vorst credible~off-site accidents vere therefore performed to determine the adequacy of th>> protection against such accidents that is offered by the control rooa habitability systems. The results of these analyses are presented in Section 2.2.3.3.2.
SK'PP FSAR concentrated so that by plume travel time over the distance from the railroad to the intake structure at the SHNPP plant, a sufficient concentration would remain so as to pose a potential concern. The frequency of calm wind conditions has been subtracted from the total wind direction frequency since under calm winds, the plume would either meander so dramatically that no concentration would be received onsite or the plume would "puddle" around the location of the release to spread in a uniform manner in all directions'he probability of an event under Pasquill stability type "F" and the probability of an event under Pasquill stability type "G" for the entire hazardous travel distance of 8.2 miles is the sum of the values calculated for each sector, resulting in a combined annual probability less than 10 per year; thus the release of a hazardous material due to a railroad accident is not a design basis event.
2.2.3.3.2 AC.C-I d~~)
-Eh~m Release<of Chlorine Chlorine is the only toxic chemical which poses a threat to control room personnel as a result of an accidental release either onsite or offsite.
Three cases have -been evaluated with regard to the consequences of a chlorine release, including a truck accident release, a rail car release, and a rail car release at the site. In all cases it was assumed that the chlorine containers ruptured and the contents were instantaneously released at the close'st point to the control room ventj.lation intake.
Q~ ~~~~'eF ~) jg~)( ~gg ~(f+Q@ol WJYlWc 4 G/~ M<l car Q re
< >p~+acct~
The design m e impact. on< ezy~l ra~~
of the Circulating and Service Water Chlorination System at the
~e. r4duo4ec(.
SHNPP includes the use of one 55 ton rail tan a a storage vessel for chlorine. This car is located approximately
~ at a point where*predominate winds blow away inaj j,s'i? a from the Control Room, the plant.
The hazards associated with this method of chlorine storage at the plant site have been evaluated in accordance with Regulatory Guide 1.95, Rev. 1, as noted in Section 1.8. As a result< it has )een cgnclgded>ghat, assumin~@atal rupture of one tank carP the safety measures mac'orpoAaec xn<tne plant'esign IZEGXi~
'l'1 are adeqgqte t~o proJect control as
't detailed below.
' room peqgqnnel ~ The Control Room will be r4 WoM c e. loca.
Add>> W+sc~ 8 Redundant chlorine detectors are located at the storage area between the tank car and the Control Room. Detectors are also located at the control room ventilation intakes. The Control Roo hus rotected a ainst t ects of rupture during normaL storage nd urin car moy ent Thes detec ors v a ' " .:pp . d ect s s sit ity nd se point re.'
ic't'o::
g .o to'ity he.'tr tee'h ri.' i.'i ite -'ro .to p event he, c tr r om 'm.-'. c din th iini -('l5 ) discu ed in t G de .78<. Signals from t ese c lorxne detectors wxL a) Initiate alarms in the Control Roen.
2.2.3-22a Amendment No. 27
INSERT
'8'ull cars will be brought to the site approximately three times a year. According to Regulatory Guide 1.78, rail shipments less frequent than,30 times per year need not be considered in evaluating control room habitability. There-fore, an accident involved in the movement of the chlorine tank car onto the site is not a design basis event.
INSERT
'C'hese detectors are calfbrated for 0 - 10 ppm full scale. Under all credible accident condftions involving releases of liquid chlorine, high chlorine concentrations in the chlorine storage area will cause the detectors to generate an alarm and isolation signal in the control room before the chlorine reaches the control room outside air intake. A leak of gaseous chlorine through, say, a stuck open or sheared-off relief valve would cause the local detectors to alarm and isolate the control room. In such a case the operators would have sufficient warning to don breathing apparatus before the concentration in the control room reached 1>>~ J<ppr nEcvNngcwA(zg u <y~hfey Bura~ A7c~-
directs the control room air through charcoal filter beds.
gp Zn addition, posit pressure, full-face, self-con%ined, breathing apparatus are stored in the Control Room.
~
+ Addi Wpi~vEchlorine releases any 'lo'herefore, either onsite or offsite will not present a hazard to the control room personnel.
2.2.3e4 Fires The only fire hazard in the vicinity of the SHNPP is the potential delayed ignition of flammable vapor clouds associated with a propane line break. This information is discussed in Section 2.2.3.2.
2.2.3.5 Collision with the Intake Structure The SHNPP site is not located on a navigable waterway, therefore this section is not applicable.
There are no storage facilities for oil or liquids which may be corrosive, cryogenic, or coagulant, located where failure of the facility would allow these materials to be drawn into the intake structures and affect the plant's safe operation.
2.2.3.7 Aircraft 0 erations Evaluation A discussion of aircraft operations is contained in Section 3.5.1.
2.2.3-22b Amendment No. 20
I
@pe gy f g I g/jest lo~A dW-s'5c
/ruck and rail car accidents vere analysed using the atmospheric dispersion and transport models described in R,G. 1.78, 1.95 and 1.145.
Meteorological data vms taken from Table 2.3.3-13, vhich lists the )oint frequencies of stability class and lover level vind speeds for the years 1976-1978. This table vas selected since it spanned the longest contiguous time period and since the frequencies are presented vith much greater precision than in the table for the later period (1979-1980). All combinar4ons of vind speed and stability class having non-sero frequencies for the N'fl sector vere considered, vith each vind speed range being represented by its mid-point.. The initial release and dispersion of the chlorine vms calculated according to "he model described in NlJRE~570.
Control room operators vere assumed to don self-contained breathing apparatus vithin tvo minutes of the actuation of the high chlorine I
concentration alarm, aa specified in ReGe le78e Tvo different chlorine release accidents vere postulated:
- 1) an accident involving the release of 20 tons of chLorine from a truck on US Highvay 1, 6,965 feet north-northvcst of the plant
- 2) aa accident involving the release of 90 tons of chlorine from a railroad tank car'n the tracks of the Seaboard Railroad, 10,740 feet north-northvest of the plant
O~'--iTe Ai-I o8 --+~
The folloving data vas used in both<analyses:
Seight above ground of fresh air intake Outside air exchange rate (normal operation)
Isolation valve closure time
'0 i ft
.887 volumes/hour 15 sec Infiltration rate after isolation Response. time of chlorine detector probe ~ 20 sec (toS~ ppm chlorine concentration)
Electronic processing time of signal 3 ' sec infiltratiog rate
/'he isolated vas calculated as follows:
R ~ (L+ r)60 2 V R ~ Infiltration'ate after isolation
~ /fg vol/hr leak rate under 1/8" v.g P
L Assumed ~ pressure Qg cfog r ~ infiltration rate due to op ning and closing of doors
~ 10 cfm V Free air volume of control room envelope M 710000 ft (The values of L and r are highly conservative.)
OrV-Sz7z wad The results of the analyses show that, for all credible A off-site chlorine release ac idents the ch'orine concentration in rhe control room remain veil below( g~>,z until the operators donned their breathing apparatus ~
SHNPP FSAR 6.4 HABITABILITYSYSTEMS The Control Room Habitability Systems include equipment, supplies and procedures which give assurance that the control room operators can remain in the Control Room and take effective actions to operate the nuclear power plant safely under normal conditions and maintain the facility in a safe condition following a postulated accident as required by the General Design CzXC5XCh contained in Appendix A to 10 CFR 50. C i%~i'cn 2'f The habitability systems and provisions include:
~atda'.
a) Control Room Air Conditioning System (which includes the Emergency Fiitration System). Mega 'k~
b) Radiation protection p~~ p c) Food and water storage
~d ~cV d) Kitchen and sanitary facilities
) MlcWiWe. and The above systems Mt n]'ho~
provisions
~ Ere.~i+
under norma+
operating conditions, (including the design basis loss of coolant accident) and postulated release of toxic gasessmoke~~ceeaai.
~~d 6e4 F 1 DESIGN BASIS Replace. Thet"ha itabi ity~sy em:"for.'heYCont ol'.-tRoomf Aced 'Bee ding - r"r /
mH4. i'it 'tionpr nd~r'pur gcsItLo "'syst'm +'t'emper're~'a ~hum itypco rot~/ '
rad ation; n'd,",detox '>c'hemi'~ins't entati" n~, suf. eke'n "~st 'ra" "for"fo d art Ws 'eiftii +o'tlisur; .'route ns:to r :xte.n'de% c'cupen by~ 't'rol % 'oai: p'e'r'onn-ee ncl.udi j'kitch n(and'.- nitary~ acili'ti The bases upon which the functional design of these systems and provisions are designed include the following:
Control Room Envelo e:
The control room envelope includes, in addition to the Control Room, the following auxiliary spaces:
a) Office areas b) Relay and termination cabinet rooms c) Kitchen and sanitary facilities d) Component cooling water surge t'ank room 15 6.4.1-1 Amendment No. 15
peal The habitability systems for the Control Room include shielding, air handling and filtration systems, temperat control, dehumidifiers, instrumentation to protect ag nN airbo ne radioactivity and chlorine, air breathing apparatus, a sufficient storage for food and water, and other pro-visions for extended occupancy by control room personnel, in eluding Kitchen and sanitary facilities,
SHNPP FSAR Peri,od of Habitabilit Replace The co rol. ro ,envel e has b hn design for con nuous oc pancy plank c dit'ionsi Following a'design sis accord'-
Z~
under'oth ormal~ d='u'pse the systems're d'esned-"to crate co tinuously or at le t one mont houR p nned.,m"" ntenance and to- b capable o operatin intermitt tl~forg t leist..one-""yea without jor ove aul.
~Ca acit 15 The Control Room has been designed (1) to allow continuous occupancy of five persons for a seven-day period fo'llowing a design basis accident and (2) for replacement of the crews following the seven days. This includes sufficient food, water, medical supplies and sanitary facilities.
Food Water, Medical Su lies and Sanitar Facilities For habitability of the Control Room during certain emergencies, a seven-day supply of food and potable water is provided within the control room area.
Basic medical supplies, kitchen and sanitary facilities are provided within the control room envelope.
Radiati,on Protection:
The Control Room envelope has Peen designed to ensure continuous occupancy during normal operation and extended occupancy throughout the duration of any one of the following postulated design basis accidents:
a) Loss of coolant accident (LOCA) b) Fuel handling accident c) Radioactive releases due to radwaste system failure The radiation exposures shall not exceed 5 rem whole body for the duration of any of the above accidents.
t"hler-iN Protection Automatic i.solation of the control room air intake@4s provided for m~ce ~l
~d-i~~
+on~
t zaha~n upon detection ofAhigh chlorine concentration. Refer to Section 6.4.4.2 for a discussion of Hat'~ gas protection.
Chlorine Res irator E e and Skin Protection for Emer encies n adequate number of respirators is provided in the Control Room for emergency use.
6.4.1-2 Amendment No. 15
The period of habitability for control roan operators is based on the habitability systems'apability to provide protection fran the intrcduction into the control rcan envelope of airborne oontaminants that present an irmediate danger to life or health. The nest severe hazards are posed by chlorine and airborne radioactivity. Following the detection of chlorine demand breathing apparatus,
~pe After the detection of airborne radioactivity the ccntrol.
roan envelope will be pressurized and all air will be filtered
&~h coal adsorbers. This system will insure that the control roan operators will not receive dcses of radiation in excess of the limits specified in GDC 19 of Appendix A to 10'FR 50 during the time required for the safe shutdown of the plant.
SHNPP FSAR Habttabilit S stem 0 eration Durin Emer encies The Control Room Air Conditioning System is safety related and designated as Safety Class 3 and Seismic Category I. The system is capable of performing its functions assuming ~ single,failuze.
air conditioning
~ Q,~iie. ~~po~~
system will not promote the propagation of smoke and The fire from other areas in the Reactor Auxiliary Building to the control room envelope. Refer to Section 9.5.1 for a discussion of fire protection criteria for the Control Room. Provisions have been made for control room smoke purge operation, as described in Section 9.4. 1.2.3.
The system has been designe to maintain the ambient temperature in the Control Room at 75 F DB and QX percent (max.) relative humidity during normal conditions andaEa~~g a design basis mcident.
During a postulated UKK, the Control Room is pressurized to 1/8 in. wg. by the capability of introducing a maximum of 400 cfm outside air into the is i
Control Room which will.keep the carbon dioxide and oxygen concentrations within safe levels. Calculations of C02 and 02 concentrations within the Control Room consider that the concentrations of these gases are homogenous within the control room envelope, excluding the air above the hung ceiling.
Design maximum concentration of carbon dioxide is taken as 1.0 percent.
Design minimum concentration of oxygen will be taken as 17 percent.
During a postulated chlorine, accident fm the Control Room
~g c.xhcuAs+
air inta es will
~~d- +Q Q~~l &owl <cHGs Q QOI The Control Room has been designed t y l design basis natural phenomena agd design basis accidentsg gegposfilk fsgc.lgZprvadgcudt'n/1~,
~Emer ene Monitore and Control E ui ment
)Y6 W+
Provisions have been made to detect 'adioactivity, chlorine and room envelope is automatica ly isolated. Sensitivities of the detectors and i.sol.ation time including delays in the control circuits are designed to meet the requirements of GDC 19.
6.4.1-3 Amendment No. 15
SHNPP FSAR 6.4.2 SYSTEH DESIGN I
6.4.2.1 Control Room. Envelo e The control room envelope includes those areas listed in Section 6.4.1.
During an emergency, the areas which the control room operator could require access to are the Control Room, office areas, kitchen and sanitary facilities and control room emergency air intake valves located in the relay and termination and cabinet rooms.
6.4.2.2 Ventilation S stem Desi n
'ed control room envelope air conditioning process ~~s md'he control operation and an emergency air cleanup operation. The environmental an environmental control operation is the primary function of the air conditioning system and it is accomplished by the use of redundant air conditioning eycH~a. The Control Roon will be isolated upon receipt of a containaent isolatWo.M~isw actuation signal or following a detection at the intake opening of radioactivity or smoke. In addition, the Control Room is isolated upon tCiQH t LC detection of chlorine either remotely or at the contro room air intak opening per the requirements of Regulatory Guide 1.95 9%8 Section 1.@.
Redundant, motorized butterfly valves are provided At control room envelope outside air intake and exhaust ducts for automatic isolation of the system from the surrounding atmosphere. Consequently, the normal ventilation system is not expected to have any adverse effects on the control room habitability during a design basis accident.
Redundant trains of the Control Room Air Conditioning System are provided for the system to fulfillits
- o. essential functions. The redundant filtration train is located irg.separate equipment room/. The system is located within the Reactor Auxiliary Building which is designed to withstand effects of the safe-shutdown earthquake and other design basis natural phenomena.
utom Eically a uated, red dant isola on valves re provide at the no a) uts de aLr i ke and ex ust air pat so that he control oom envelo c e ompletel isolated f om the outs e atmosp re. The sy tern is desi ned t cform it gsafety fu ions and m ntain a itable env onment in e Control Room Air Conditioning System is designed to Seismic Category I requirements. This includes ~ equipment and ductwork up to and including the connection into the Control Room (excep the normal exhaust and urge fans). The air intakes and exhaust of the Control Room Areas Ventilation System are tornado and missile protected.
Active system components meet the single failure criteria as described in IEEE-279-71. Refer to Table 9.4.1-4 for a single failure analysis'f the Control Room Air Conditioning System.
6.4.2-1 Amendment No 15
SHNPP FSAR The redundant air conditioning units are served by separate Essential Services Chilled Water Systems so that 'loss of one train of the chilled water systems wi11 not affect the abil'ity of the system to control the thermal environment in the control room envelope.
'The Control Room Area Ventilation System including equipment, ductwork, valves, and air flows for both normal and emergency modes is discussed in detail in Section 9.4.1. Design data for principal components of the Control Room Area Ventilation System are presented in Table 9.4.1-1. The airflow diagram for the Control Room Area Ventilation System is shown on Figure 9.4.1-1.
The Emergency Filtration System is discussed in Section 9.4.1.2. The operational status of valves, fans and corresponding airflow rates for the Control Room dir'onditioning System and Emer piltration System are 15 prevented in Table 9.4.1-2.'he design data i cl ng o ype spe cat iltra and g filtape. typm and s fi tion for t e ass~gene arco n syst presented in a e iS The degree of compliance of the Emergency Filtration System with the requirements of Regulatory Guide 1.52 is discussed in Section 6.5.1.
The layout drawings of the Control Room showing doors, corridors, stairwells, shield walls, and the, placement and type of equipment within the Control Room 15 are shown on Figure 1.2.2-35. Elevation and plan views showing building dimensions and the location of control room air intakes are also presented on 15 Figure 1.2.2-35.
ac. Ied. ~ ~4+~<~P Under a completely isolated Control Room,lithe COy concentration would build up from zero to one percent in 142 hours0.00164 days <br />0.0394 hours <br />2.347884e-4 weeks <br />5.4031e-5 months <br />. This buildup time is based upon a net 15 control room envelope of .71 x 10 ft which includes space above the egg crate hung ceiling and a ~~a~rate of 4$ R3HB/hr FQC'+~dyyqg ZAliN/
In order to ma ntain CO concentrations below 0.5 percent one-hal the design w ~~~~
n.e '--* =----
t<+~ I.,CO z, i 15 basis value) outside air would have to be introduced at a rate of ptr~fm.
Since the mode of the Control Room Ventilation System permits the 15 continuous introduction of up to 400 cfm (outside air from the uncontaminated air intake),
15 ACId
'-nsMC~ .49 dbf IItys ventilation rate of will maintain
~
A 0./C cfm fresh ai g per person the oxygen level in the Control Room at 17 percent 15 t design ventilation rate capability of up to 400 cfm is>adequate.
We/fyffz i~ Redundant smoke detectors are provided at the system main return duct for annunciation of fire alarms and for stoppage of the system fans. Smoke purge fans are provided to expedite fire fighting efforts. Refer to Section 9.4. 1. 2.3 for a detailed discussion of the smoke purge, operation.
Amendment No. 15 6.4.2-2
~ ln>>> 4R Can&L t'd<~ See sn a"4'(A.a C
6z uo, s<gmzv~ dustup os CO~ pi Pa <<rzoZ <oorn I r s~ ul~i't, 1XfRf l3,e pV gq$ uw<~~,m s 4f ~~ lail' JCM>>~,~CJ 4~ 4~~ Q ~W~ - e p~>&uL p<zsc~~ 44'~+c4 g </g ~~ Q mo~aqau~
SHNPP FSAR e
cc rrec+(v'c. 9zrnccdn.rcg grC9CCd~ 8 The use of self contained breathing apparatus has been considered in the development of for chlorine release. T)~~6 calla( for immediate donning of breathing apparatus by the operators on detection of g j>qyg chlorine in the Control Roomfhw <<v5$ $ g(gc74A jan/ fjjf cf/ZD+f C4A CEIVf~gjO~
Adequate bottled air capacity (of at least six hours) is readily available onsite for the five Control Room occupants to assure that sufficient time is available to locate and transport bottled air from offsite locations. This offsite supply is capable of delivering several hundred hours of bottled air to the members of the emergency crew.
~cA> 0 d) 4Y~gfe( ~U/~
Th control room envelope is pressurized to 1/8 in. of water yaug re a ve to N+e. Che at all times during normal plant op continuously introduced to the control room envelope iong gutside air is mum rate of 400 cfm in order to maintain 1/8 "inch of water gauge. Folio g a s n "bas acc ent the C rol in n a osit e re ure di erential of 1/8a pres ze
, ~tra f
of water au e The pressurization flow rate is approximately 0.34 volume change per hour. During nMes~r~o
~ ~-
a postulated chlorine accident, the Control Room air intakes will isola'te a I.F closed~ c~J I C,~W M~MS All openings to c'~
the Control Room have a low leakage design. This includes doors, valves, penetrations and walls. The control room leakage rate estimate through valves, doors, penetrations and walls is shown in Tables 6.4.2-1 and 6.4.2-2. The estimate is based on Ma.Ale ~ ~ 'W~~ ~
AEC RSD Report NAA-SR-101000.
os a to th co tro1 operator mhhtmar. exceed thegose Amdt of. General Design criterion 19 of Appendix A to 10 CFR 50 under design basis accidents. An acceptance test is performed at startup to verify>
~u g~
~m( (n +Re ~a/yS<5'~
P~g~f rCrb IS )MS,+hi g 94 4<4~
g 6.4.2.4 Interaction with Other Zones and'ressure-Containin E ui ment The following provisions are taken into consideration in the Control Room Area Ventilation System design to assure that there are no toxic or radioactive gases and other hazardous material that would transfer into the Control Room:
a) The control room envelo e is pressurized to 1 8 in. w. . relative to t e adjacent areas r i a~e~~ro~hK" GnA~ ~at
't e-*xcr-frtdaerz'rp c.r, ctccgdtnMI nhlctnht. release.
b) The Control Room Area Ventilation system is independent and completely separated from other adjacent ventilation zones.
< veloF'~
~
c) There is no other HVAC equipment within the Control that serves other ventilation zones.
All doors, duct Room
'penetrations are of low leakage design-d) and cable e) 1 sure- ainin n s, pmen nd pi e iso fr e C trol om.
6.4.2-3 Amendment No. 15
The ccntrol roan is. autamatically isolated following a de 'asis radicnuclide or chlorine release accident.
In case of a radionuclide accident, the operator will re-pressMrize the control roan by drawing in filtered outside air through one of two emergency air intakes.
SHNPP FSAR 6+ 4,2. 5 Shieldin Desi n The Control Room envelope is shielded against direct sources of radiation which are present during normal operating conditions and following a postulated accident.
There are no significant sources of direct or streaming radiation near the control room envelope during normal operating conditions. The shielding walls and floor provided for the accident conditions are more than sufficient to limit the dose rates to less than 0.25 mr/hr. in the Control Room during normal operation. Refer to Section 12. f a discussion of the control room shielding design. 024
- 6. 4. 2-4
SHNPP FSAR TABLE 6 '.2-1 CONTROL ROOM BUTTERFLY VALVES LEAKAGE RATE ESTIMATE 1 ~ COMPONENTS: Butterfly valves in:
a) Exhausts b) Normal Outside Air Intake SIZE: 12 inch diameter (exhaust) 16 inch diameter (intake)
QUANTITY:
~
Four (2 valves arranged in series in pat&
~a~ csP ~
LEAK RATE AT 13.8 PSIG: 0.018 (0.024) cubic fe~) per day per exhaust (intake) valve o.53 LEAK RATE AT + 1/8 INCH W.G. .~ x 10 cfm per two valves 2~ COMPONENTS: Butterfly valves in:
a) Purge Exhausts b) Purge Make-Up SIZE: 30 inch diameter (exhaust) 36 inch diameter (make-up)
QUANTITY: Four (2 valves arranged in
'e~
st in each )Bit}iX~~c LEAK RATE AT 13 ' PSIG: 0.045 (0.054) cubic feet ~er day per exhaust (make-up) valve LEAK RATE AT + 1/8 INCH W.G ~ x 10 cfm per ~r valves 3 COMPONENTS: Butterfly valves in'.
Post-Accident Ait Intakes (~ts)
SIZE 12 inch diameter QUANTITY: Four (2 valves arranged in series in each '/ROID cd'~~ ~+As)
LEAK RATE AT 13 ' PSIG: 0.018 cubic feet per day per valve LEAK RATE AT + 1/8 INCH W.G ~ ~x -6 10 cfm per two valves 25 0.=31) -~
Zy2) ~x TOTAL LEAKAGE TO THE OUTSIDE x 10 cfm FROM VALVESe l 10 cfm Wr- ec,)-g~c Wig~
D>gg 3) '/GAL X 10 cfm
~.> <<c c<)
TOTAL = ~x 10 cfm i S ~~-c1 ~
6.4.2-5 Amendment No. 25
SHNPP FSAR TABLE 6.4.2-1 (cont'd)
NOTES:
- 1. There are a total of 12 isolation valves> f %~i'>1 ~ ~ ~ ~gQ~%~g~~
two in series in eac pat~ g However, it has valve closes in each path following control room been assumed that only one isolation.
- 2. Based on AEC R&D Report NAA-SR-101000, Reference 2, Section A-2, p LIZ-105.
- 3. For control room positive pressure +1/8 inch w.g.
6.4.2-6 Amendment No. 15
TABLE 6 ' '-2
SUMMARY
OF MAIN CONTROL ROOM LEAK RATE CALCULATION C.P Q NWBER OF LEAKAGE TOTAL Q?9 PAlH NUMBER REFERENCE LEAKAGE COEFF IC I ENT PER UNIT COMPONENT NO, COMPONENT UNIT OF UNITS DETAIL (I) A 8 AP+EP I/2(2) LEAKAGE Hol low metal door, metal 3g-Ox7g-0 AOS I I I-A-2 4,0 22,0 8,28 Interlocking gasketed weath'tr lpplng, door opening fn(g ~teen)~ egend ) $ ~g) /cga ex/o-~ ~~)g'.e cgocO4 '
2.
3, 4~
Door Frames Wa1 Slab ls Ft, Ft,
/0 'Boo ag (p~ Oocg AOS ADS I-A-7 I-A-24)
ADS I-A-2(gE')
I
~~
m~
l)(/D JX/C 0
0 0
125)(/o
,~~I,zSA/0+~.
~ gCO
()o)4S 5 Juncture of f loor Ft, Q5Q 4SQ ADS I-A-3C/) 1,6x 10 0 .2 IO+
slab and wall 6, Eave Ft (/5~ ~ ADS Case 2 I-A-5 6x 10 ~ 75x 10 14 7~ Corners, columns and Ft, 340 ADS I-A-6 1,6x 10 .210 5 wall Joints with Q~ t
~ 0007 8
c aulklng Penetratlons for Ft, 78G ADS I I I%-I I 3xlO 1625x 10 ~ +E31 f Q
~
~
electrical cables 9~ Penetratlons for HVAC ducts In. of /t~P~ ADS I I IW-I I ~ 3x 10 ~ )62%(10 ~OK/4 t Sea I Case 2
- 10. Isolation Butter f I y ADS A-2 IO 6(4) m Valves Case 2 a 11 Pipe Penetratlons In. of //Q %01 IW-I f$ ~I
~. l4VIIC. 8 ~If ~~~
Opening and closing of doors Q~CL + gay ADS I I Case 2 Note (3)
I ~ 3x 10 ~ 1625x10 i<$
10.00 0002 Tote I (I) Bbsed on AEC RS Report NAA-SR-10100 (2) Leakage est)mate based on AP=O. 125 In w,g.
(3) See standard review plan Sect)on 6.4 1113d211 (4) See Table 6.4.2-1
SHNPP FSAR 6.4.3 SYSTEM OPERATIONAL PROCEDURES The normal operation of the Control Room Areas Ventilation System is discussed in detail in Section 9.4.1.2 L'p the post accident operation and smoke purge operation of the control room areas are discussed in detail in Sections 9.4.1.2.2 and 9.4.1.2.3.
Upon failure of the normal power supply, al.l el.ectrically operated safety related components of the system will be automatically switched to their respective emergency power source.
~cl e,yhau~s Upon receipt of an SIAS signal or high radiation signal from the radiation monitor located within each air intake, all outside air intake wiLL be automatically isolated and the Emergency Filtration System (including booster fans and air handling units) will be put pinto operation.
After a high radiation signal has automatically isolated the Control Room Air Conditioning System (CRACS) the operator wil.l monitor the CRACS air intake radiation detectors and select the emergency air intake from which to draw the least radioactive make-up air. This selection will be based on the readings of the radiation detectors located in the redundant air intakes on either side of the Reactor Auxili Building. The controL room operator will manually open the selected lose ir intake be4m<~ allowing up to a maximum of 400 cfm of the outside air into the control room envelope.
positive pressure of L/8 inch water i:ng':actu"L'~
'l'-" 'pur Q maintain a
,;eo e,gauge~-
Depe
>, 'il'ie w,ttie-o e
-efm" ger:.,
.n~u>w<
gWCh
',<even't;wind'",
'me e; u oper
<<exprpw are.u tia'ng'.oc f en: etue, jil]u eguue eb'1"'.t'"teh, uch~t at'!'xctou tamx ated~
iO+,gcJVA.. ~i .W'um 4't u'ruuu rsvp ~r-;is" .g di'att'la xrtmura.
i ,, audi'at e."-eg~ um'~O'
-,tile-ac ve ax ;ant'a ,->5 iia ra atmo a ar ~wil
~ ~,
~ r> '." >,'.'u", u.,
':."s
~~'uuuuim-r ded;-
I~ '
- "L'e've " v'er- cee '.-th .fix ~hi
- g i'gh'." adi: son.. tpo" ,.",'t erne ency 'x inta ";wi'Lt.,agai b'- to ic'al'~i.'s'o " t'ed - Re r'.-t ' e'r-for discuss of t ins umen at
- n:and'nt'rsy'"" e4.
s et o .ope *, io 'll'" ov, '.
9 u 'r~ +0 uu(4 t u PJpek+ Oubl
"'ta 'W ted~; ,esker lto-" e~' o rol ri nsuu~ng",
': t~ur+ u tj'a .o:~t e~ p'igh -cont'iiat'et ' 1'+ g 1+8+I l)$
Q
',.aai- er-.
'e'Li od'd'-, ~x. sur -thh;th ", oie~ s'~oN ner'a es n~
ri ria ari 't.". c'cede .
A4 d~~~ ~ a ~~k~~orl In the e n o xgh chlorine daaaB~ at the control room air intakes or at the chlorine storage site, all control room air intakes wil automatically be isolated and the Emergency Filtration System will be activated.
-~~tg~ ~)ov~ ~
Control Room
~ec@e.
Air
~~~4~
Conditioning System will continue to operate in the
@he complete recirculation mode, with no fresh air intake for the duration of the exposure. Buildup of C02 in the control room envelope during this short period will not exceed safe limits. Refer to Section 6.4.2.2.
0 ~Re.-~ cv.v- rn9e- mH-4In44 ~ye ~< '7l+o l~~ +~;~
a+ ~ ~ ~I ~ ~~~d~~ae~+e be. Cb termbQ tot~le=&4p ~d 6 t-xeroxed + J e toeaL beets
+4 QGQ C+N Tnm4~ .'Gr,r D ~i~Cd l4 'Ae. MdiDlti.!<ru(CLr~+rtr, 6.4.3-1 Amendment No. 25
SHNPP FSAR 6.4.4 DESIGN EVALUATION 6.4.4.1 RadioLo ical: Protection The evaluation of the radiological. exposure to the control room operators is presented in the .control room accident dose analysis given in Chapter 15.
Section 15.6.5.4.4 shows the doses following the design basis accident (LOCA) and demonstrates compliance with GDC 19.
6.4.4.2 Toxic Gas Protection Accidents involving hazardous chemical releases are discussed in Section 2.2.3.
The significant source of toxic chemicals Located onsite is a 55-ton rai 1 tank
i car of liquid chlorine which is used in the CircuLating and Service Water Chlorination System. The tank car is located near the Cooling Tower, at a distance of about ~60 ft. from the nearest Control Room normal air t't intake'~
""ch'c's',,'<<g'>>u d .b
'" 'g',at;<j h o' gn i t so'rce
" f"<" xi' '
'r'~ orf 'k, 'd out in>pc,'>>ai 'a'.~~i
' <<i ~/+ gg+ w<<g
":d'u','"
'o. d.
":d',<> .</~~ <<g: c p<%>>
i'p nt j
~
~
o L;i ",ch i he.
r '1'p e'4 'a i't 'o's '---'i;" 'at aYdi'a' e" o ~a e~ ~. d' t" p<<z4: ~ 's~ it ~f]l'<<AP~>><<
gjZA5% f1AAW1
'~f e+'.'i;e
',k~ 'thite-.an
~o
+WAN>><<;<<<<W~>>
c<<cT. ent a" a<<c ei eii', b is,, 'ei's '-fo,.tnto ic) c e Ls .whi -"are-st'or d'o tr nsp r."te 4 No. l~The
.'o'ff,ate'me design of the Control Room at the SHNPP includes quick response redundant chlorine detector system sensor probes Located in the Control Room's normal air intake, emergency air intakes, and by the chLorine storage area and handlin facilit The chlorine detector system's electrochemical sensor probes are a polarographic probe operating at zero applied potential between a platinum and silver electrode. The combination of the electrolytes used in the cell at zero applied potentiaL provide a sensor probe that is highly specific to chlorine. High reliability is ensured with an eLectronic system of solid state design and a detector system which requires no material consumption except to detect chlorine.
In the presence of chlorine, the potential between the probes changes initiating a signaL to the system's processor unit. The processor unit determines whether the transmitted signal is a valid chlorine detection or a system malfunction. If a vaLid chLorine signal is detected, a signaL is transmitted to the system's controL unit which initiates control room isolation. Specific system malfunctions are aLarmed; however,. the system is fail safe and wilL provide control room isolation. Maintenance activities, such as calibration, will be performed in accordance with manufacturer's recommendation.
6.4.4-1 Amendment No. 21
0 e th d para aph iPV n/X<%7 There are no significant off-site stationary sources of toxic chemicals within a five mile radius nf SHNPP Toxic chemicals are transported by
~
truck over US HighM>y 1, and by tank cnr over the tracks of th Seaboard Railroad, thc two transportation routes nearest to the plant. The potential hazards from railroad accidents involving releases of toxic chemicals other than chlorine have been evaluated in Section 2.2.3.3.1.
The probability that such an accident could pose a threat to control room
<<7 personnel was found'to be less than 10 per year, obviating the consideration of such a release in evaluating control room habitability.
/owJl~~g The potential hazards resulting from off-site chlorine release accidents vere evaluated in Section 2.2.3.3. Two design basis 'accidents vere selected: thc complete loss of lading of a 20-ton tank truck ~
p~
on US 1 or of a 90-ton tank car on the Seaboard Railroad, both at points of nearest approach to SHNPP. Neither accident posed ~ threat to control room habitability under the worst credible aeteorologicai conditions.
~AQE+ 7 ~o. Z The senten in the fourt aragraph of ~ section eted on the attached aarke p copy, sh be replac th the f ving X'NX o These detectors are calibrated for 0 - 10 ppa full-scale and coaply vith the intent of Regulatory Guide 1.95, as discussed in Section 1.8. Upon sensing a high chlorine concentration, they vill generate a signal vhich vill isolate and alarm the control room,
SHNPP FSAR s
The Leakage rate of the control room HVAC valves are given in, Tables 6.4.2-~
and 6.6.2-2. The valves that isolate the control room outside air intakesgare esj.gned with a ~ second closure time. The Control Room Area Ventilation System is discussed in detail in Section 9.4.1.
The control room design calls Eor a fresh air turnover rate of approximately O-'I M volume chan e er hour inside the controL room HVAC envelo e during normal peration. T re re, ssu ng max um az inl age ate f 0 6 vo mes per ou fo ow' is ati n, e Co trol ooms all i to ntr Roo Type Add in in egul tory uid 1.9 , Rev l. abLe rox'tel equ to t e m in imuegu allotoryableuid .95 d
M1~W i loxca ne s t at 55 ons
'ent s a Nc,3 1 0 et Er a y i pe a s CongLe ol onta'ner R om.
w ich c b stor d at a di an of ikew', e qu ntit whi c be res ted a 6 50 ft is ch g ate than 0, 0 lb . Consequently, the control room design provides adequate protectI.on Eor control room operators from accidents involving release of chlorine both onsite and offsite. In addition, fulL face Scott Air Packs are stored in the Control Room. The sac(sam of Pvbc< d ~v<5 for chlorine release5cal lg for immediate donnin of the z hjjh breathing apparatus by the operators on detection ~ chlorine in t e Control Room Adequate bottled air capacity of at least six hours is available for the control room occupants as discussed in Section 6.4'.2.2. couezuAa7ioW pit< w1hKra'ucf'/4'e cA&pr~ s7gggp PW'.
Toxic chemicals stored onsite are listed in Table 6.4.4-1. SuLfuric acid and sodium h droxide do not resent dangers to controL room habitabiLit because ey are non-volatiLe. 8 'des lo e, er xc , i. , ni ge a n ox an yd gen, re 'm Le s h ants nd be me us ar n ncen tio s in xr. Since an anaLysis based on Regulatory Guide 1.78 shows that the concentration of these gases in the Control Room will be below one percent under the condition of, accidental release, these gases have no potential Eor adversely affecting control room habitability.
Refer to Section 1.8 for the SHNPP position on Regulatory Cuide 1.78.
6.4.4-2 Amendment No. 21
The atad p of the ~ nd para p on ~ 4<<
uld replaced the f ovfn nrxsar h/o. 8 p outleakage~of .06 vol+ace per hour under ~ poaitive preaaure of 1/g" vater gauge folloving ieolation, the control room QEKEB fulfilLs the requireaenta for Type V of R,C. 1.55, Tab)e 1, for the purpoae oi evaluating on-site releaae, vith the clafification noted in Section 1.8.
The aaxieuia quantity atored in a aingle tank (55 tone), at the apecified diatance of 1,580 feet from the control rooe, ia vithin the aliovable liait calculated froa the data in Tab fo( gQ (gg NZ 7 T'e ed part the t d para on .4.4-h d be repl ed the f oving !
XA'sÃAprA&.
Hydrogen and nitrogen are aiaple asphyxiante and vould poae a threat to control habitability only i! they vere to apprecikLy reduce the oxygen concentration in the control room, vhile carbon dioxide levels of up to 1Z can be tolerated for a lioited period of time.
SHNPP FSAR J
I ~
TABLE 6.4 ~ 4-1 TOXIC CHEMICALS STORED ONSITE DX~AHc~
HORIZONTAL GEEKKIHBE FROM NO. OF TANKS/ THE CONTROL ROOM NORMAL TOXIC CHEMICAL LOCATION CAPACITY, EACH VENTILATION INTAKE, FT.
Sulfur'.c Acid At Cooling (H2S04) Tower 1/7800 gal. 950 (ice /) At Turbine Bldg 1/5473 gal. 400 At Water Treat. Bldg. 1/7820 gal. 530 Sodium Hydroxide At Cooling Tower 1/1700 gal. 1000 At Turbine Bldg 1/8883 gal. 380 At Water 1/10,500 gal. 750 Treat. Bldg.
Nitrogen 'Gas Storage 1 system/ 700 (N2) (Liquid) Area 10,584 lbs.
Carbon Dioxide Gas Storage 1 system/ 700 (C02) (Liquid) Area 4,000 lbs. liquid 1,290 lbs. vapor Oxygen Gas Storage 1 System/ 700 (02) Area 60,400 scf Hydrogen Gas Storage 1 System/ 700 (H ) (Liquid) Area 1,500 gal.
Chlorine Storage Shed 1/110,000 lbs (Cl ) (Liquid) At Cooling Towers 6.4.4-3 Amendment No. 19
SHNPP FSAR 6,4.5 TESTING AND.INSPECTIONS e.Hc (
The maj or items of equipment require to maintain the habitability of the Control Room are the harcoal filter trains, mechanical refrigeration water chillers, fans and fan coil units, and chilled water pumps. These units are thoroughly tested in a program consisting of the following:
a) Shop component qualification thst.
b) Field preoperational tests.
These systems and their components, which maintain Control Room habitability, are subjected to documented preoperational testing and in-service surveillance Sections 6 ',
to ensure continued integrity. Testing and inspection is also discussed in Section 3.9.6.
9.4.1.4, and 14.2.12. Pump and valve testing is delineated in Tests are conducted to verify the following for both normal and emergency conditions.
a) System integrity and leaktightness.
b) 4~ng Inplace testing of emergency filter ghamaN to establish Leaktightness
~pKhamm and design parameters of the high-efficiency particulate air and charcoal filters.
c) Proper functioning of system components and control devices.
d) Proper electrical and controL wiring.
e) System balance for design airflow, water flow and operational pressures.
Ern 6.4.5.1 Charcoal Filter Trains Initial performance verification and periodic surveillance tests~a -~~ ~ ~e<y conducted to ensure operability and performance of both su~~ charcoal filter systems. Components in these filter systems have been designed to, and are tested in accordance with, the codes and requirements cited within Regulatory Guide 1.52 (see Section le8) ~
6.4.5.2 Water Chillers During shop testing the water chiller impellers are subjected to an overspeed test and dynamic balancing. This overspeed test is in excess of 125 percent of the impeller operating speed. The rotor part of the compressor drive motor 20 is dynamically balanced. Preoperational testing in the field is discussed in Section 14.2. Inservj.ce inspection on the. safety Class 3 components of the chillers will be performed in accordance with Section 6.6 ~
- 6. 4. 5-1 Amendment ho 20
SHNPP FSAR 6.4 '.3 Fan or Fan Coil Units Fan impeLlers are subjected to static and dynamic balancing. Cooling coiLs are hydrostatically pressurized and Leak tested. A performance test or manufacturer's certified rating in accordance with Air Moving and Conditioning Association (AMCA) or Air Conditioning and Refrigeration Institute (ARI) standards is required. PreoperationaL testing is delineated in Section 14.2.12 'perating fan or fan coil units will be checked periodicaLLy for unusual vibration and high bearing and motor temperatures.
6.4.5.4 ~Pum s Each chilLed water pump is tested to verify the pump perfo'rmance characteristics. Preoperational testing shall be delineated in Section 14.2.12. Operating pumps wiLL be observed for Leaks, suction and discharge pressures, and flowrates. The pumps wilL be rotated periodicaLLy.
t 6.4.5.5 Considerations Leadin to the Selected Test Fre uenc The frequency of performing the surveillance tests is determined by the following considerations:
a) Preoperational test data.
b) NormaL control room area ventilation system performance data.
c) Continuous monitoring of the Control Room Area Ventilation System, which gives an indication of building tightness and system performances 6.4.5-2 Amendment No. 22
SHNPP FSAR 6.4. 6 INSTRUMENTATION REQUIREMENT The control room air conditibning system instrumentation is designed to assis'4 'Kc ~j ~ .,+c, v I~A rnaebrtaCii habitability conditions in the Control Room wieh=m&imum attemZon'- Ero~he=opeeacos. System instrumentation, control switches and alarms on the Main Control Board provide the operator with the information concerning the status of the system and enables the operator to take the proper course of action.
System instrumentation and control switches, with the exception of those for the emergency filtration trains and emergency intake valves, are located on the auxiliary control pane+for use when the Control Room is evacuated.
/M~..~Qd'-r Pa.n~4 The alarms such C
a n. "
radiation monitors are provided with adjustable setpoints and associated that the operator is notified if any predetermined increase in radiation levels occurs at the egmuahh5g air Xntake5 /hi n ' v u Qi ouch o " '
I 'o r dkf~fussgi af r 'c 'ri
<<I In the event that the high radiation setpoint is reached, the normal outside air and emergency air intakesjare J ~
f wc~~~ ct 'st<(e~ ~ +see automatically isolated. The, &~~~9 ~ill ~cjAMWc ~~(~>>Styr g~(
l<a<V receicec+<v'e, 4 vc.<m The radiation detectors and displays meet the requirements for the post accident monitoring systems including IEEE-279, as discussed in Sections q~(..rj~~ ~~(
7.3, Cnuc.In~i 11.5 and 12.5.
Chlorine detectors are located adjacent to the chlorine storage facility and jQmf~
Section ~
in each outside air intake of the Control Room.
Hhigh chlorine concentration automatically closes all air intakes c nd to the Contr. 1 Room. For detailed discussion of chlorine detection see Z. 2 ndicators are provided for the emer enc air intake flow to dundant flow show the operator eisa~
o'w Tbao t='the flowrat ago .s s; ,t in M ts of 00 1... 'a u ', e"fomay~ d at as, t e n e io 6
'e t
g'ecy:
nt
'i 3 M~~ck W ff <WU.<i try+iw) 19 Smoke detectors are provided at the normal outside air intake and throughout the control room area In .the event of a smoke alarm in the control room area, the operator manually initiates the smoke purge fans which convert the ~rnt~hcf&
Control toom EVAC System to a "once through" system. If smoke is detected at
'4-he HVAC System+'Q~ jQ Qc ~~ ~C. y.~~
The following Control Room Air Conditioning System parameters are monitored and alarmed when abnormal conditions exist:
a) Normal outside and emergency air intake radiation level b) Normal outside and emergency air intake chlorine concentration Amendment No. 19 6.4.6-1
SHNPP FSAR c) Chlorine storage area chlorine concentration d) Normal outside air tnt'ake smoke concentration e) Control room area smoke concentration f) Control room air handling unit prefilter differential pressure g) Control room air handling unit inlet temperature h) Control room air handling unit+eating and~cooling coil ou ide temperature ~( f.~)g~
Control room air handling unit fan failure (low flow) j) Control room exhaust fan failure (low flow) k) Control room purge fan failure (low flow)
- 1) Control room pressure (relative to ~8K)=+he. ad~et(.eA+0 s~
m) Emergency air intake fan failure (low flow) n) Emergency air filtration train status (diff. press.)
o) Emergency air filtration train humidity p) Emergency air filtration. train inlet temperature q) Emergency air filtration train charcoal filter status Refer to Sections 7e3 and 7.5 for a more detailed discussion of the control room air conditioning system instrumentation and controls.
6.4.6-2 Amendment No. 14
SIL'HAPP FSAR 9.4.1 CONTROL ROOM. AREA VENTILATION SYSTEM I Z7 The Control Room Area Ventilation System consists of an Air Conditioning System and an emergency filtration system to serve the Control Room.
27 Additional details of the Control Room Area Ventilation and habitability systems are given in Section 6.4.
9.4.1.1 Desi n Bases The Control Room Air Conditioning System/ (CRACS) provides heating, relative humidity ~~
ventilation, cooling, filtration, air intake and exhaust isolation, and 50pqrcgo7 for the control room envelope (as described in Section 9.4.1.2) during normal operation and kahhae~ a design basis accident.
Systems are designed to include the effects of the most adverse single active component failure.
The high energy piping systems outside containment are listed and described in Section 3.6A.2. Those listed systems are the CVCS, SGBS, FWS and the AFS. A discussion of the analysis is provided for those systems in Section 3.6A.2 that demonstrate that the Control Room will not be adversely affected by a pipe crack or break in an adjacent area. Figure 3.6A-2 shows the only high energy piping adjacent to the Control Room with indication of break locations and jet impingement envelopes.
The steam lines near the Control Room (elevation 305 feet) ia located in the turbine building at elevation 286.00 feet and separated by the Category I wall of the RAB. The Control Room, including outside air intakes for control room ventilation will not be adversely affected by any high energy pipe breaks.
The main steam line may be slightly radioactive but as discussed in Sections 15.1.5, 6.4.4 and 9.4.1 radiological impact would be limited to below acceptable levels by ventilation systems and wall shielding.
The Control Room Air Conditioning is designed:
a) To maintain the Control Room at a design temperature of 75 F dry bulb 27 and maximum relative humidity -not to exceed 50 percent, assuring personal comfort as well as suitable environment for continuous operation of controls and instrumentation.
b) To detect the introduction of radioactive material into the Control Room and automatically isolate all air intakes and exhausts upon a high v7 radiation signal or SIS signal and to remove airborne radioactivity from the Control Room to the extent that dose to the Control Room operator following a I Z7 design basis accident does not exceed the limit specified in the General Design Criteria 19.
c) To operate in conjunction with the Fire Detection System to remove smoke from the Control Room in the event of fire.
9.4.1-1 Amendment No. 27
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SIL'IPP FSAR d) To detect and limit the introduction of chlorine into the Control Room 27 by automatic isolation of air intakes and exhausts upon detection of high chlorine concentrations at the outside air intakes or adjacent to the chlorine storage area. The environmental effect pertaining to control room habitability following a design basis accident and chlorine exposure accident
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is discussed in Sections 2.2.3 and 6.4.4.2.
e) To be powered by the redundant Channel A and Channel B ESF buses.
f) To meet single active component failure in the system or a failure in a single emergency power supply coxncxdent with loss of offsite power.
g) To meet Safety Class 3 and Seismic Category I requirements and to be tornado and missile protected. 7g< pr 27 +~~<~>
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h) To permit testing, adjustment, and inspection of the principal system components on a regular basis to assure system functional reliability.
9.4.1.2 S stem Descri tion The control room envelope, which is referred to as the "Control Room,"
incLudes, in addition to the Control Room, 'the following auxiliary spaces.
a) Office area b) Relay and termination cabinet rooms c) Kitchen and sanitary facilities d) Component cooling water surge tank room The computer rooms, protection and control equipment rooms, communication rooms, instrument repair room, and cable vault located in the Reactor Auxiliary Building are ventilated and cooled by independent cooling systems.
The Control Room Air Conditioning System is shown on Figure 9.4.1-1 and principal system components design data are listed and described in Table 9.4.1-1.
The CRACS is designed to maintain the control room envelope at a design 27 temperature of 75 F under normal and Design Bases Accident conditions. Space relative humidity is controlled not to rise above 50 percent. The air is cooled by a cooling coil. The chilled water supply to the cooling coil is provided by the Essential Services Chilled Water System (see Section 9.2.8).
27 When heating is required, the air is heated by the electric heating coils to maintain the design space temperature stated above.
9.4.1-2 Amendment No. 27
SIL'HAPP FSAR 9.4.1.2.1 Normal Operation During normal operation, the Control Room Air Conditioning System operates in a recirculation mode with the Emergency Filtration System de-energized. The outside makeup air mixes with the returned air before air handling units. The Control Room is maintained at a slightly positive it is conditioned by the pressure with respect to so that the air from other sources entering the Control Room is minimized. The pressurization of the Control Room is maintained automatically by means of modulating exhaust 27 fan dampers.
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Each of the two supply air handling units are served by common supply'and return ductwork with all necessary accessories to make the system complete and operable. All chilled water to the cooling coils is provided by Essential Services Chilled Water System (see Section 9.2.8).
9.4.1.2.2 Post Accident Operation Upon receipt of a SIS, high radiation at the outside air intake or high chlorine concentration signal at the outside air intakes or adjacent to the 27 ) chlorine storage area, a Control Room Isolation signal is generated and the following functions are performed automatically.')
All- isolation valves at the normal outside air intake will close.
b) All isolation valves in the Control. Room Smoke Purge System will close (these valves are normally closed).
27 c) Both emergency filtration units will. start and their respective valves will open for 'full recirculation mode.
d) All isolation valves in the Normal Exhaust System will close and the operating exhaust fan will be de"energized.
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e) Dampers for lavatory and kitchen which normally by-pass the return system will open.
Following the completion of the above automatic functions, the operator will perform the following tasks:
a) Place one of the two emergency filtration trains on standby.
27 b) Select and open one emergency outside air intake path during radiological accident to pressurize the Control
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Room (these paths are normally closed). ~
9.4.1-4 Amendment No. 27
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S1L'IPP FSAR function (refer to Table 9.4.1-4). Butterfly valves andlor dampers are provided to isolate flow through affected heating/cooling units as necessary. Redundant units are provided to assure adequate cooling or heating as required. Mal.functioning HVAC equipment can be readily identified and isolated from the Control Room. There is no significant effect to the control room environment from the isolated malfunctioning train. Heating and cooling equipment for the Control Room are remotely located and are not in the Control Room.
In any event, the design of the plant is such that the Control Room can be evacuated and the plant can be maintained in a safe condition from the auxiliary control panel (refer to FSAR Section 7.4.1.11). The auxiliary control panel area is serviced by totally independent HVAC units.
e) The ventilation system has sufficient redundancy to preclude inadequate heating or cooling as described in Section 7.3.1.5.7 and as shown on Figure 7.3.1-17 and Table 9.4.1-4.
The adequacy of the CRACS to limit thgdos$ toqersonnel is demonstrated in Chapter 15> Sec~w ~S 4 . 5 / Cx:~h <~~
Detection of radioactivity in the control room environment is provided by i~a,k radiation monitors as described in Sections 11.5 and 12.3.4. This system Q wd ..X4 permits immediate and automatic isolation of the control room normal and ~Ra emergency outside air ucts upon receipt of a xgh radiation signal and 27 enables the operator to select the least contaminated emergency outside air intake for control room pressurixation. Adjustable high radiation alarms are provided to alert the operator of changes in contamination levels at both post-accident air intakes. The control room area ventilation system isolates 27 all paths to the environment upon receipt of a high radiation signal as described in FSAR Section 6.4.3.
Smoke detectors in the Control Room will actuate an alarm so that the operator can initiate the smoke purge operation in the event of a fire.
Protection of Control Room personnel against an onsite chlorine release is achieved by automatic isolation of the Control Room and the use of breathing apparatus by the control room operators. For detailed evaluation of chlorine incident and safety precautions and equipment see Sections 2.2.3, 6.4.4.2 and 9.5.1.2.3(c).
~in fL CLS Control Room air intake chlorine detector trip signals will cause automatic iu(ed i< isolation of the Control Room and will provide an audible alarm to the
~c.c+) c;g1 l t5 operators The means used to initiate automatic isolation meet single active ax ure and Sex.smxc Category I criteriak The remote chlorine detection system complies with the requirements of Regulatory Guide 1.95, revision 1, with the clarifications stated in Section 1.8.
room isolation will be accomplished within bee seconds after l5'ontrol detector trip. Openings to the Control Room will have a low leakage design~ ~R-a~do~he'-r4 ~ ~ ~
vct@rcsc.and.ta cbns~hgua This includes doors, valves, and penetrations.
9.4.1-6 Amendment No. 27
SIL<PP FSAR p DZLK7 g e x uM@ng/'f Normal. fres axr makeup x.s am@ted to one
~"~j8 air change per hour. a mxnxstrative procedure will specify that doors leading to the Control Room be kept closed when not in use.
See Section 9.5.1 for the protection of the CRACS from the effects of fire.
9.4.1.4 Ins ection and Testin Re uirements The CRACS undergoes preoperational and startup tests as described in Section 14.2.12.1.58. Periodic tests are required as described in the Technical Specifications (see Section 16.2). Inservice inspection requirements are described in Section 6.6. Valve testing requirements are described in Section 3.9.6.
9.4.1-6a Amendment No. 27
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SIC'O'P FSAR TABLE 9.4.1-1 (continued)
- 2. Motors Quantity, Total. 1 per fan Type 25 Hp, 460 V, 60'Hz, 3 phase, Horizontal Induction Type Insulation Class H
> >g~ g,H Enclosure and Ventilation TEFC Code NEMA, l5585%%I Class lE
- 3. HEPA Filters Quantity, Total Banks 2 per unit Cell size 24 in. high, 24 in. wide, 11-1/2 in., deep Max. resistance clean, in. wg.. 1.0 Max. resistance loaded, in. wg. 210 Efficiency 99.97 perce'nt when tested with 0.3 micron DOP Material Glass or glass asbestos paper separated by aluminum inserts, supported on cadmium plated steel. frame
- 4. Charcoal Adsorbers Type Multiple gasketless bed cells in air-tight housing Quantity, Total 1 per unit Material Impregnated coconut shell (Meeting the requirements of ANSI-N509, Table 5.1, year in effect at purchase)
Depth of bed (in.) 4 ina Face velocity (fpm) 40 Average atmosphere 0.25 seconds per 2 in. of residence time adsorber bed 9.4.1-9 Amendment No. 27