Regulatory Guide 1.52

Design, Testing, and Maintenance Criteria for Engineered-safety-feature Atmosphere Cleanup System Air Filtration and Adsorption Units of Light-Water-Cooled Nuclear Power Plants

ML13350A197
Person / Time
Issue date:	07/31/1976
From:	Office of Nuclear Regulatory Research
To:
References
RG-1.052, Rev. 1
Download: ML13350A197 (11)

U.S. NUCLEAR REGULATORY COMMISSIONREGULATORY GUIDERevitton 1July 1976OFFICE OF STANDARDS DEVELOPMENTREGULATORY GUIDE 1.52DESIGN, TESTING, AND MAINTENANCE CRITERIA FOR ENGINEERED-SAFETY-FEATURE ATMOSPHERE CLEANUP SYSTEM AIR FILTRATION ANDADSORPTION UNITS OF LIGHT-WATER-COOLED NUCLEAR POWER PLANTSA. INTRODUCTIONGeneral Design Criteria 41. 42, and 43 of AppendixA, "General Design Criteria for Nuclear Power Plants,"to 10 CFR Part 50, "Licensing of Production andUtilization Facilities," require that containment atmos-phere cleanup systems be provided as necessary toreduce the amount of radioactive material released tothe environment following a postulated design basisaccident (DBA) and that these systems be designed topermit appropriate periodic inspection and testing toensure their integrity, capability, and operability.General Design Criterion 61 of Appendix A to Part50 requires that fuel storage and handling systems,radioactive waste systems, and other systems that maycontain radioactivity be designed to ensure adequatesafety under normal and postulated accident conditionsand that they be designed with appropriate confinement, and filtering systems. General DesignCriterion 19 requires that adequate radit'ion protectionbe provided to permit access to and occusaucy of thecontrol room under accident conditions and for theduration of the accident without personnel radiationexposures in excess of 5 I.futo the whole body.This guide pres!"4 nertods acceptable to the NRCstaff for implernr-ting" e Commission's regulations inAppendix A, tiO CFl Part 50 with regard to thedesign, te .g, afti imilinance criteria for air filtrationand ada T atmosphere cleanup systems inlight-water- ed nuclear power plants. This guideapplies onlyy engineered-safety-feature atmospherecleanup systems designed to mitigate the consequencesof postulated accidents. It addresses the atmospherecleanup system, including the various components andductwork, in the postulated DBA environment.B. DISCUSSIONAtmosphere cleanup systems are included as en-gineered safety features in the design of liglil.witer.cooled nuclear power plants to mitigate the c0rs,..quences of postulated accldwnts by removing fr',rn thebuilding or conltailliment atmosphere radioactive mnateralthat may be rtdeased in the accident. All such cleanupsystems should be dsiped it) operate uider theenvironnmental conditions resulting from die accideit.in this guide, atmosphere cleanup systems that nitistoperate under postulated DBA conditions inside theprimary containment (i.e., recirculating systems) aredesignated as primary systems. Systems required tooperate under conditions that are generally less severe(Le., recirculating or once-through systems) are desig-nated as secondary systems. Secondary systems typicallyinclude the standby gas treatment system and theemergency air cleaning systems for the fuel handliiigbuilding, control room, and shield building.The DBA environmental conditions for a Livensystem should be determined for each plant. DBAenvironmental conditions for typical primary andsecondary systems are shown in Table I. In addition.primary systems should be designed to withstand tieradiation dose from water and plateout sources in thecontainment and the corrosive effects of chemical sprays(if such sprays are included in the plant design).An atmosphere cleanup system consists of sonic or allof the following components: demisters, heaters. pre-filters, high-efficiency particulate air (HEPA) filters,adsorption units, fans, and associated ductwork, valv.ing, and instrumentation. The purpose of the decnister isto remove entrained water droplets from die inletUSNRC AEGULATORY GUIDES Comments ftould be sent to the Secetatev of the Commit$'*r U 6 Nuclse,Reegulatorl Commission. Wathington. 0 C 2OU. Attention Doielblim and~Regulatory Guides ate ilsued to describe and make available to the public Service Sectiomtmethods eoeet6able to thl NRC ,e:If of implementing specific perts of iheCommission'e seouleione. 0 adlhnete' techniques used by the $tlef in vei1u the guides spa Issued in the following ton broad divisionscling specific problems or pOS1ulated accidents, or to piovidte guidance to epplicen.t Regulatory Guides or* not substitute$ iegulalitlln and complience I Power Reactors 6 Productswith them is not (iquired Melthods and solutions dilt cent from those eel ou0 in 2 Research and Telt leactore 1 Transportationthe guides w)iI be acceptable it they provide a basis tlo the findings requisite to 3 Fuels end Metesiels Facilities 8 Occupational Htelththe issuance at continuance of a permit or license by the Commission 4 Environmental Silti 2 Antitrust Comments and sugg6esti01l for improvement; in those guide% ate encouraged 5 Materials enid Pllnt Protection 10 Generalat ell limes, and guides :ill be revised me epptoprlete to accomrnodate camments and Io reflect new information ao edaperince Howovee. comments on Copies Of pubtlthed guides mar be obteined by writen request indicating tirethis it #rCeived wilhin about two months aftr 4lte istsuince will be per divisione desired to the U S Nuclear Regulatory Comnseteion Washington DChiculeil usslUl in evaluating thi neimed to-n e.lrly rvii.On 20%5 Atlentuon Direcio, 011,c of Siendedl enstlopmlntit stream. thereby protecting pretilters, HEPA filters, andadsorbers front water damage awd plugging. Heaters.when used on secondary systems, normally follow thedemisters in the cleanup train and are designed to mixand heat the incoming stream to reduce the stream'srelative humidity before it reaches the filters andadsorbers.Prefihters and HEPA filters are installed to removeparticulate matter, which may be radioactive. Prefiltersremove the larger particles and prevent excessive loadingof HEPA filters; to some extent dernisters may a!soperform this function. The HEPA filters remove the finediscrete particulate matter and pass the air stream to theadsorber. The adsorber removes gaseous iodine (ele.mental iodine and organic iodides) from the air stream.IIEPA filters downstream Df the adsorption units collectcarbon fines. The fan is the final item in an atmospherecleanup train.The environmental conditions preceding a postulatedDIA may affect the performance of the atmospherecleanup system. Such factors, for example, as industrialcontaminants, pollutants, temperature, and relativehumidity contribute to the aging and weathering offilters and adsorbers and reduce their capability toperform their intended functions. Therefore, aging andweathering of the filter: and adsorbers, both of whichvary from site to site, should be considered during designand operation. Average temperature and relativehumidity also vary from site to site, and the potentialbuildup of moisture in the adsorber should also be givendesign consideration. The effects of these environmentalfactors on the atmosphere cleanup systemn should bedetermined by scheduled testing during operation.All components, of atmosphere cleanup systemsshould be designed for reliable performance underaccident conditions. Initial testing and proper mainte.nance are primary factors in ensuring the reliability ofthe system. Careful attention during the design phase toproblems of system maintenance can contribute signifi-cantly to the reliability of the system by increasing theease of such maintenance. Of particular importance inthe design is a layout that provides accessibility andsufficient working space so that the required functionscan be performed safely. Periodic testing during opera.Lion to verify the efficiency of the components isanother important means of ensuring reliability. Built-infeatures that will facilitate convenient in-place testingare important in system design.Standards for the design and testing of atmospherecleanup systems include draft standard ANSI N509,'Lines indicate substantyv- changes from previously publishedregulatory guide."Nuclear Power Plant Air Cleaning Units and Comnpo.rients" (Ref. 1), and ANSI N510.1975, "Testing ofNuclear Air Cleaning Systems" (Ref. 2).Other standards are available for the construction andtesting of certain components of systems. Where suchstandards are acceptable to the NRC staff, they arereferenced in this guide. Where no suitable standardexists, acceptable approaches are presented in this guide.ORNL.NSIC-65, "Design, Construction and Testing ofHigh-Efficiency Air Filtration Systems for Nuclear Ap-plication" (Ref. 3), provides a comprehensive review ofair filtration systems. It is not a standard but a guidethat discusses a number of acceptable design alternatives.C. REGULATORY POSITION1. Environmental Design Criteriaa. The design of an engineered-safety.feature at.mosphere cleanup system should be based on themaximum pressure differential, radiation dose rate,relative humidity, maximum and minimum temperature,and other conditions resulting from the postulated DBAand on the duration of such conditions.b. The design of each system should be based onthe radiation dose to essential services ih the vicinity ofthe adsorber section integrated over the 30.day periodfollowing the postulated DBA. The radiation sourceterm should be consistent with the assumptions found inRegulatory Guides 1.3 (Ref. 4), 1.4 (Ref. 5), and1.25 (Ref. 6). Other engineered safety features, incluingpertinent components of essential services such aspower, air, and control cables, should be adequatelyshielded from the atmosphere cleanup systems.c. The design of each adsorber should be based onthe concentration and relative abundance of the iodinespecies (elemental, particulate, and organic), whichshould be consistent with the assumptions found inRegulatory Guides 1.3 (Ref. 4), 1.4 (Ref. 5), and 1.25(Ref. 6).d. The operation of any atmosphere cleanupsystem should not deleteriously affect the operation ofother engineered safety features such as a containmentspray system, nor should the operation of other en-gineered safety features such as a containment spraysystem deleteriously affect the operation of any atmos-phere cleanup system.e. Components of systems connected to compart.ments that are unheated during a postulated accidentshould be designed for postaccident effects of both thelowest and highest outdoor temperatures used in theplant design.*11.52-2 2. System Design Criteriaa. Atmosphere cleanup systems designed and in.stalled for the purpose of mitigating accident dosesshould be redundant. The systems should consist of thefollowing weqt..ntial components: (1) demisters, (2)prefilters (Gemisters may serve this function), (3) HEPAfilters before the adsorbers, (4) iodine adsorbers (impreg.nated activated carbon or equivalent ads.,rbent such asmetal zeolites), (5) HIEPA filters after the adsorbers, (6)ducts and valves, (7) fans, and (8) related instrumenta.tion. Heaters or cooling coils should be used when thehumidity is to be controlled before filtration.b. The redundant atmosphere cleanup systemsshould be physically separated so that damage to onesystem does not also cause damage to the second system.The generation of missiles from high-pressure equipmentrupture, rotating machinery failure, or natural pheno-mena should be considered in the design for separationand protection.c. All components of an engineered-safety-featureatmosphere cleanup system should be designated asSeismic Category I (see Regulatory Guide 1.29 (Ref. 7))if failure of a component would lead to the release ofsignificant quantities of Fission products to the workingor outdoor environments.d. If the atmosphere cleanup system is subject topressure surges resulting from thie postulated accident,the system should be protected from such'surges. Eachcomponent should be protected with such devices aspressure relief valves so that the overall system willperform its intended function during and after thepassage of the pressure surge.e. In the mechanical design of the sy: tem, thehigh radiation levels that may be associated with buildupof radicactive materials on the system componentsshould be given particular consideration. System con-struction *materials should effectively perform theirintended function under the postulated radiation levels.The effects of radiation should be considered not onlyfor the demisters, heaters. HEPA fidters, adsorbers, andfans, but also for any electrical insulation, controls,joining compounds, dampers, gaskets, and otherorganic-containing materials that are necessary for opera-tion during a postulated DBA.f. The volumetric air flow rate of a single cleanuptrain should be limited to approximately 30,000 cfm. Ifa total system air flow in excess of this rate is required,multiple trains should be used. For ease of maintenance,a filter layout three HEPA filters high and ten wide ispreferred.g. The atmosphere cleanup system shovld beinstrumented to signal. alarm, and record pertinentpressure drops and flow rates at the control room.hi. The power supply and electrical distributionsystem for the atmosphere cleanup system described inSection C,2.a above should be designed in accordancewith Regulatory Guide 1.32 (Ref. 8). All instrumenta-tion and equipment controls should be designed to IEEEStandard 279 (Ref. 9). The system should be qualifiedand tested under Regulatory Guide 1.89 (Ref. 10). Tothe extent applicable, Regulatory Guide 1.30 (Ref. I I)and IEEE Standards 334 (Ref. 12), 338 (Ref. 13), and344 (Ref. 14) should be considered in the design.i. To maintain radiation exposures to operatingpersonnel as low as is reasonably achievable during plantmaintenance, atmosphere cleanup systems should bedesigned to facilitate maintenance in accordance withthe guidelines of Regulatory Guide 8.8 (Ref. 15). Thecleanup train should be totally enclosed.Each train should be designed and installed in a mannerthat permits replacennent of the train as an intact unit oras a minimum number of segmented sections withoutremoval of individual components.j. Outdoor air intake openings should be equippedwith louvers, grills, screens, or similar protective devicesto minimnize the effects of high winds, rain, snow, ice,trash, and other contaminants on the operation of thesystem. If the atmosphere surrounding the plant couldcontain significant environmental contaminants, such asdusts and residues from smoke cleanup systems fromadjacent coal burning power plants or industry, thedesign of the system should consider these contaminantsand prevent them from affecting the operation of anyatmosphere cleanup system.k. Atmtosphere cleanup system housings and duct-work should be designed to exhibit on test a maximumtotal leakage rate as defined in Section 4.12 of draftstandard ANSI N509 (Ref. 1). Duct and housing leaktests should be performed In accordance with therecommendations of Section 6 of ANSI N510-1975(Ref. 2).3. Component Design Criteria and Qualification Test-inga. The demisters installed in engineered-safety-feature atmosphere cleanup systems should meet qualifi-cation requirements similar to those found in MSAR71.45, "Entrained Moisture Separators for Fine ParticleWater-Air-Steam Service, Their Performance, Develop-ment and Status" (Ref. 16). Demisters should meetUnderwriters' Laboratories (UL) Class I (Ref. 17)requirements.1.52-3 b. Adsorption units function efficiently at a rela-tive humidity of 70%. If heaters are used on sýcondarysystems, the heating section should reduce the relativehumidity of the !ncoming atmosphere from 100% to70% during postulated DBA conditions. A prototypeheating element should be qualified under postulatetDBA conditions. Consideration should be given insystem design to mirnumizing heater control malfunction.The heater stiould not be a potential ignition adsorbentsource.c. Materials used in the prefilters should withstandthe radiation levels and environmental conditions preva-lent during the postulated DBA. Prefilters should meetUL Class I (Ref. 17) requirements and should be listedin the current UL Building Materials List (Ref. 18). Theprefilters should have not less than a 40% atmosphericdust spot efficiency rating (see Section 9 of theASHRAE Standard 52, "Method of Testing Air CleaningDevices Used in General Ventilation for RemovingParticulate Matter" (Ref. 19)).d. The HEPA filters should be steel cased anddesigned to military specifications MIJ,-F-51068D (Ref.20) and MIL-F-51079B (Ref. 21). The HEPA filtersshould satisfy the requirements of UL-586 (Ref. 22).The HEPA filter separators should be capable ofwithstanding iodine removal sprays if the atmospherecleanup system will be exposed to such sprays followinga DBA. HEPA filters should be tested individually by theappropriate Filter Test Facility listed in the currentEnergy Research and Development Administration(formerly USAEC) Health and Safety Bulletin for theFilter Unit Inspection and Testing Service (Ref. 23). TheFilter Test Facility should test each filter for penetrationof dioctyl phthalate (DOP) in accordance with therecommendations of MIL-F-5 1068D (Ref. 20) and MIL-STD-282 (Ref. 24).e. Filter and adsorber mounting frames should beconstructed and designed in accordance with the recom-mendations of Section 4.3 of ORNL-NSIC-65 (Ref. 3).f. Filter and adsorber banks should be arranged inaccordance with the recommendations of Section 4.4 ofORNL.NSIC-65 (Ref. 3).g. System filter housings, including floors anddoors, should be constructed and designed in accor-dance with the recommendations of Sections 4.5.2,4.5.5, 4.5.7, and 4.5.9 of ORNL-NSIC-65 (Ref. 3).h. Water drains should be designed in accordancewith the recommendations of Section 4.5.6 of ORNL-NSIC-65 (Ref. 3).i. The adsorber section of the atmosphere cleanupsystem may contain any adsorbent material demon-strated to remove gaseous iodine (elemental iodine andorganic iodides) from air at the required efficiency.Since impregnated activated carbon is commonly used,only this adsorbent is discussed in this guide. Eachoriginal or replacement batch of impregnated activatedcarbon used in the adsorber section should meet thequalification and batch test results summarized in Table2 of this guide. If an adsorbent other than impregnatedactivated carbon is proposed or if the mesh sizedistribution is different from the specifications in Table2, the proposed adsorbent should have demonstrated thecapability to perform as well as or better than activatedcarbon in satisfying the specifications in Table 2.If impregnated activated carbon is used as theadsorbent, the adsorber system should be designed foran average atmosphere residence time of 0.25 sec pertwo inches of adsorbent bed. The adsorber should havethe capacity of loading 2.5 ing of total iodine (radio-active plus stable) per gram of activated carbon. Nomore than 5% of impregnant (50 mg of impregnant pergram of carbon) should be used. The radiation stabilityof the type of carbon specified should be demonstratedand certified (see Section C.L.b of this guide for thedesign source term).j. If tray or pleated-bed adsorbent canisters areused in the adsorbent section. they should be designed inaccordance with the recommendations of CS.8T,"Tentative Standard for High-Efficiency Gas-Phase Ad-sorber Cells" (Ref. 25). The activated carbon should betotally restrained in the adsorber. A qualification test ona prototype adsorber should be performed in accordancewith paragraph 7.4.1 of CS-8T (Ref. 25), except that thesafe shutdown earthquake parameters particular to thesite should be used. The adsorber should be tested bothbefore and after the qualification test and should showno significant increased penetration when challengedwith a gaseous halogenated hydrocarbon refrigerant inaccordance with USAEC Report DP-1082 (Ref. 26).To ensure that the adsorber section will containcarbon of uniform packing density, written proceduresfor filling the adsorber beds should be prepared andfollowed in accordance with the recommendations ofSection 7.4.2 of CS-8T (Ref. 25).k. The design of the adsorber section shouldconsider possible iodine desorption and adsorbent auto-ignition that may result from radioactivity-induced heatin the adsorbent and concomitant temperature rise.Acceptable designs include a low-flow air bleed system,cooling coils, water sprays for the adsorber section, orother cooling mechanisms. Any cooling mechanismshould satisfy the single-failure criterion. A low-flow airbleed system should satisfy the single-failure criterionfor providing low-humidity (less than 70% relativehumidity) cooling air flow.I. The system fan, its mounting, and the ductwork,connections should be designed and constructed in1.52-4 accordance with tile recomtmendatioiss ti Section 2.7 ktORNL.NSIC.65 (Ref. 3).m. The fan or blower used on the cleanup systemshould be capable of operating under the environlmentalconditions postulated, including radiation.n. Duclwork should be designed in accordancewith the recommnendations of Section 2.8 (if ORNL.NSIC.65 (Ref. 3).o. Ducts and housings should be laid out with aminimun of ledges, protrusions, and crevices thac couldcollect dust and moisture and that could impedepersonnel or cicate a hazard to then in the performanceof their work. Straightening valnes should be installed toensure representative air flow trmeasurement and uniformflow distribution through cleanup components.4. Maintenancea. To keep radiation exposures to operatingpersonnel as low as is reasonably achievable, the atnlus-phere cleanup system should be designed to controlleakage and permit maintenance in accUrdance with thieguidlines of Regtilatory Guide 8.8 ( Ref. I5).b. Accessibility of components and maintenanceshould be considered in the design of atmospherecleanup systems in accordance with the recomninenda-tions of Sections 2.5.2. 2.5.3. and 2.5.4 of ORNL-NSIC-65 (Ref. 3).c. For ease of niaintena ice, tile system designshould provide for a minimum of three linear feet frommounting frame to mounting frame between banks ofcomponents. If components are to be replaced, thedimension to be provided should be the rnaxinun¶length of the component plus a minimum of three feet.d. The system design should provide for perma.nent test probes with external connections. Preferably,the test probes should be manifolded at a singleconvenient location, with due consideration given tobalancing Qf line lengths and diameter to produceeliable test results for refrigerant gas, resistance, flowrate, and DOP testing.e. Each atmosphere cleanup train should beoperated at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> per month, with tile heaterson (if so equipped), in order to reduce the buildup ofmoisture on the adsorbers and HEPA filters,f. The cleanup components (i.e., HEPA filters,prefiiters, and adsorbers) should not be Installed whileactive construction is still in progress.5. I~li.l~ce "lesing (Critellaa. 'lre .irllospliere cleanup system Should hitested ii i place I I ) initially. 21 at least once jle tol)eIatiIIgcycle thereaftel tor svstelnis iirauntained ini a st.urmd'.kstatus or after 720 hoturs of' sh tem tiioelidtio'n, and (31following paintilng, lire, or chemical release in anwventilation zoine communicating with the systeml. A\visual i nspecti tit ' t the systeni and all associatedcomponents should he wlade before each test ill accol.dance with the recommendationis tot Section 5 of' ANSIN5 10-1975 (Ref. 2).b. The air flow distributiot: to thie H-EPA fillets,and iodine adsorbers slihtild be tested in place inuutall\and at least once operating cycle thereafter t,11unilOrmnity. The distribution should be within +/-- 2` .,1thie average olow per unit. The testing should 1icconducted in accordance with the mecomnmerudations ,ISection 9 of "Industrial Ventilation'" (Ref. 2711 indSection 8 of ANSI N5 10.1975 (Ref'. 2).k. The in-place DOI' test for IHEPA filters shouldconf'orm to Section 10 of ANSI N510..1975 (Ref. 2tI IEPA filter sections should be tested in place (Itinitially, (2) at least once per oIperatnig cycle tihcuCattelfor systems maintained in a standby s:atus or at'let 7211hours of svsteln operation, and (3) following paintio.fire, or chemical release in any ventilanton zoneconlnlunicaling with tile systemu to Con1irill a petteti.tion of less than 0.051 at rated flow. An engineered-safety-feature air filtrationr system satist' ing this condi.tion can be considered to warrant a )99.7 remoualefficiency for particulates in accident dose evaluaroits.IIEPA filters that fail to satisfy this condition should IVreplaced with filters qualified pursuant to regulathc.position C.3.d of this guide. If the IHEPA filter bank ",entirely or only partially replaced. an in-place DO)' teitshould be conducted.If any welding repairs are necessary on. within. ,madjacent to the ducts, htousing. or mllournlting frailes. thefilters and adsorbers should be removed fronm tilehousing during such repairs. The repairs should becompleted prior to periodic testing, filter inspection. aridin-place testing. Tire use of sili,:one sealants or an% otheitemporary patching mnateial on filters. housing. nlloullt-ing frames, or ducts should not be allowed.d. The activated carbon adsorber section shouldbe leak tested with a gaseous halogenated hrydrocarbonrefrigerant in accordance with Section 12 of ANSIN510-1975 (Ref. 2) to ensure that bypass leakagethrough the adsorber section is less than 0.05%. Duringthe test the upstream concentration of refrigerant gasshould be no greater than 20 pprim. After the test iscompleted, air flow through tile unit should be main.1.52-5

-. Itained until the residual refrigerant gas in the eltluent isless than 0.01 ppm. Adsorber leak testing should beconducted whenever DOP testing is done.b. Laboratory Testing Criteria for Activated Carbona. The activated carbon adsorber section of theatmosphere cleanup system should be assigned thedecontamination efficiencies given in Table 3 for ele.mental iodine and organic iodides if the followingconditions are met:(1) The adsorber section meets the conditionsgiven in regulatory position C.5.d of this guide,(2) New activated carbon meets the physicalproperty specifications gi'.r in Table 2, and(3) Representative samples of used activatedcarbon pass the laboratory tests given in Table 3.If the activated carbon fails to meet any of theabove conditions, it should not be used in engineered-safety-feature adsorbers.b. The efficiency of the activated carbon adsorbersection should be determined by laboratory testing ofrepresentative samples of the activated carbon exposedsimultaneously to the same service conditions as theaasorber section. Each representative sample should benot less than two inches in both length and diameter,and each sample should have the same qualification andbatch test characteristics as the system adsorbent. Thereshould be a sufficient number of representative sampleslocated in parallel with the adsorber section for estimat-ing the amount of penetration of the system adsorbentthroughout its service life. The design of the samplerssh-ould be in accordance with the recommendations of iAppendix A of draft standard ANSI N509 (Ref. I.Where the system activated carbon is greater than twoinches deep, each representative sampling station shouldconsist of enough two-inch samples in series to equal thethickness of the system adsorbent. Once representativesamples are removed for laboratory test, their positionsin the sampling array should be blocked off.Laboratory tests of representative samples shouldbe conducted, as indicated in Table 3 of this guide, withthe test gas flow in the same direction as the flow duringservice conditions. Similar laboratory tests should beperformed on an adsorbent sample before loading intothe adsorbers to establish an initial point for comparisonof future test results. The activated carbon adsorbersection should be replaced with new unused activatedcarbon meeting the physical property specifications ofTable 2 after the last representative sample has beenremoved and tested or if any preceding representativesample has failed to pass the tests in Table 3.0. IMPLEMENTATIONThe purpose of thii section is to provide informationto applicants and licensees regarding the NRC staff'splans for using this regulatory guide.This guide reflects current NRC staff practice. There.fore, except in those cases in which the applicant orlicensee proposes an acceptable alternative method, thestaff will use the method described herein in evaluatingan applicant's or licensee's capability for and perform-ance in complying with specified portions of theCommission's regulations until this guide is revised as aresult of suggestions from the public or additional staffreview.1.52-6 REFERENCESI. Draft Standard ANSI N509 (Draft 9 -November1975), "Nuclear Power Plant Air Cleaning Units andComponents," American National Standards Institute.2. ANSI N510-1975, "Testing of Nuclear Air Clean.ing Systems," American National Standards Institute.3. ORNL-NSIC-65, "Design, Construction, and Test-ing of High-Efficiency Air Filtration Systems for NuclearApplication," Oak Ridge National Laboratory, C.A.Burchsted and A.B. Fuller, January 1970.4. Regulatory Guide 1.3, "Assumptions Used forEvaluating the Potential Radiological Consequences of aLoss of Coolant Accident for Boiling Water Reactors,"Office of Standards Development, U.S. Nuclear Regula-tory Commission (USNRC).5. Regulatory Guide 1.4, "Assumptions Used forEvaluating the Potential Radiological Consequences of aLoss of Coolant Accident for Pressurized WaterReactors," Office of Standards Development, USNRC.6. Regulatory Guide 1.25, "Assumptions Used forEvaluating the Potential Radiological Consequences of aFuel Handling Accident in the Fuel Handling andStorage Facility for Boiling and Pressurized WaterReactors," Office of Standards Development, USNRC.7. Regulatory Guide 1.29, "Seismic Design Classifica-tion," Office of Standards Development, USNRC.8. Regulatory Guide 1.32, "Criteria for Safety-Re-lated Electric Power Systems for Nuclear Power Plants,"Office of Standards Development, USNRC.9. IEEE Std 279-1971, "Criteria for ProtectionSystems for Nuclear Power Generating Stations," Insti-tute of Electrical and Electronics Engineers.10. Regulatory Guide 1.89, "Qualification of ClassIE Equipment for Nuclear Power Plants," Office ofStandards Development, USNRC.11. Regulatory Guide 1.30, "Quality AssuranceRequirements for the Installation, Inspection, and Test-ing of Instrumentation and Electric Equipment," Officeof Standards Development, USNRC.12. IEEE Std 334-1974, "IEEE Standard for TypeTests of Continuous-Duty Class IE Motors for NuclearPower Generating Stations," Institute of Electrical andElectronics Engineers.13. IEEE Std 338.1971, "Trial-Use Criteria for thePeriodic Testing of Nuclear Power Generating StationProtection Systems." Institute of Electrical and Elec-tronics Engineers.14. IEEE Std 344-1975, "IEEE Recommended Prac-tices for Seismic Qualification of Class lE Equipmentfor Nuclear Power Generating Stations," Institute ofElectrical and Electronics Engineers.15. Regulatory Guide 8.8, "Information Relevant toMaintaining Occupational Radiation Exposure As LowAs Is Reasonably Achievable (Nuclear Power Reactors)."Office of Standards Development, USNRC.16. MSAR 71-45, "Entrained Moisture Separatorsfor Fine Particle Water-Air-Steam Service, Their Perfor-mance, Development and Status." Mine Safty. Appli-ance Research Corporation, March 1971.17. Standard UL-900, "Air Filter Units," Under-writers' Laboratories (also designated ANSIB 124.1-1971).c0.. Underwriters' Laboratories Building MaterialsList.19. ASHRAE Standard 52-68, "Method of TestingAir Cleaning Devices Used in General Ventilation forRemoving Particulate Matter, Section 9," AmericanSociety of Heating, Refrigerating and Air ConditioningEngineers.20. MIL-F-51068D, "Filter, Particulate. Iligh-Effi-ciency, Fire-Resistant," Military Specification, 4 April1974.21. MIlF.51079B, "Filter Medium, Fire-Resistant,High-Efficiency," Military Specification, 29 March 1974.22. Standard UL-586, "High Efficiency, Particulate,Air Filter Units," Underwriters' Laboratories (also desig-nated ANSI B132.1-1971).23. USERDA (formally USAEC).Health and SafetyBulletin, "Filter Unit Inspection and Testing Service."U.S. Energy Research and Development Administration.24. MIL-STD-282, "Filter Units, Protective ClothingGas-Mask Components and Related Products: Perform-ance-Test Methods," Military Standard, 28 May 1956.25. AACC CS-8T, "Tentative Standard for Hligh-Effi.ciency Gas-Phase Adsorber Cells," American Associationfor Contamination Control. July 1972.1.52-7 26. USAEC Report DP.1082, "Standardized Nonde-structive Test of Carbon Beds for Reactor ConfinementApplication," D.R. Muhlbaier, Savannah River LUbora-tory, July 1967.27. American Conference of Governmental IndustrialHygienists, "Industrial Ventilation," 13th Edition, 1974.28. ASTM D2862-70, 'Test for Particle Size Distri.bution of Granulated Activated Carbon," AmericanSociety for Testing and Materials.29. ASTM El 1-70, "Specifications for Wire ClothSieves for Testing

Purpose

s," American Society forTesting and Materials.30. RTD Standard M16-IT, "Gas-Phase Adsorbentsfor Trapping Radioactive Iodine and Iodine Com-pounds," USAEC Division of Reactor Development andTechnology, October 1973.31. A.G. Evans, "Effect of Intense Gamma Radiationon Radioiodine Retention by Activated Carbon,"CONF-720823, Proceedings of the Twelfth AEC AirCleaning Conference, 28-31 August 1972.32. ASTM D2854-70, "Test for Apparent Density ofActivated Carbon," American Society for Testing andMaterials.1.52-8 TABLE 1TYPICAL ACCIDENT CONDITIONS FOR ATMOSPHERE CLEANUP SYSTEMEnvironmental Condition Atmosphere Cleanup SystemPressure surgeMaximum pressureMaximum temperature of influentRelative humidity of influentPrimaryResult of initial blowdown60 psi280" F100% plus condensingmoistureSecondaryGenerally less than primary" I atilt180" FI 00A.Average radiation levelFor airborne radioactive materials 106 rads/hra 105 rad'For-iodine build'p on adsorber 109 radsa 109 rad:Average airborne iodine concentrationFor elemental iodine 100 mg/m3 10 mg/rFor methyl iodide and particulate iodine 10 mg/m3 I mg/maThisvalue isbased on the source term specified in RegulatoryGuide 1.3 (Ref. 4)o: 1.4 (Ref. S).asapplicable.s/hr"s2n331.5 '2TABLE 2PHYSICAL PROPERTIES OF NEW ACTIVATED CARBONBATCH TESTSa TO BE PERFORMED ON FINISHED ADSORBENTACCEPTABLE TESTMETHODTESTACCEPTABLE RESUL iG1. Particle size distribution2. Hardness number3. Ignition temperature4. Activity cS. Radioiodine removalefficiencya. Methyl iodide, 250Cand 95% relativehumiditydb. Methyl iodide, 800Cand 95% relativehumidityc. Methyl iodide, incontainmented. Elemental iodineretention6. Bulk density7. Impregnant contentASTM D2862 (Ref. 28)RDT M 16-IT, Appendix C(Ref. 30)RDT M16-1T, Appendix C(Ref. 30)CCI4 Activity, RDT M16-1T.Appendix C (Ref. 30)RDT M 16-1 T (Ref. 30),para. 4.5.3, except 95%relative humidity air isrequiredRDT M 16-IT (Ref. 30),para. 4.5.3, except 800Cand 95% relative humidityair is required for test (pre-and post-loading sweepmedium is 250C)RDT M16-IT (Ref. 30),para. 4.5.4, except durationis 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> at 3.7 atm.pressureSavannah RiverLaboratory (Ref. 31)ASTM D2854 (Ref. 32)State procedureRetained on #6 ASTM El Ib Sieve:Retained on #8 ASTM El !b Sieve:Through #8, retained on #12 Sieve:Through #12, retained on #16 Sieve:Through #16 ASTM E IIb Sieve:Through #18 ASTM El 1b Sieve:95 minimum0.0%5.0% max.40% to 60%40% to 60%5.0% max.1.0% max.330*C minimum at 100 fpm60 minimum99%99%98%99.9% loading99% loading plus elution0.38 glml minimumState type (not to exceed 5% by weight)'A "batch test" is a test made on a production batch of a product to establish suitability for a specific application. A "batch ofactivated carbon" is a quantity of material of the same grade, type, and series that has been homogenized to exhibit, within reasonabletolerance, the same performance and physical characteristics and for which the manufacturer can demonstrate by acceptable tests andquality control practices such uniformity. All material in the same batch should be activated, impregnated, and otherwise treated underthe same process conditions and procedures in the same process equipment and should be produced under the same manufacturingrelease and instructions. Material produced in the same charge of batch equipment constitutes a batch: material produced in differentcharges of the same batch equipment should be included in the same batch only if it can be homogenized as above. The maximumbatch size should be 350 ft3 of activated carbon.bSee Reference 29.OThis test should be performed on base material.dThis test should be performed for qualification purposes. A "qualification test" is a test that establishes the suitability of a product fora general application, normally a one.time test reflecting historical typical performance of material.Chis test should be performed for qualification purposes on carbon to be installed in primary containment (recirculating) atmospherecleanup systems.1.52-10 TABLE 3LABORATORY TESTS FOR ACTIVATED CARBONACTIVATED CARBON2BED DEPTHb2 Inches. Air filtration systemdesigned to operate inside primarycontainment.2 inches. Air filtration systemdesigned to operate outside theprimary containment and relativehumidity is controlled to 70%.4 inches or greater. Air filtrationsystem designed to opeiate outsidethe primary containment andrelative humidity is controlled to70%.ASSIGNED ACTIVATED CARBONDECONTAMINATION EFFICIENCIESElemental iodine 90%/Organic iodide 30"V1Elemental iodine 95%Organic iodide 95%Elemental iodine 99%Organic iodide 99%LABORATORY TESTS FOR AREPRESENTATIVE SAMPLEcPer Test 5.c in Table 2 for a methyliodide penetration of less than ! 0%.Per Test 5 b in Table 2 at a relativehumidity of 707c for a methyliodide penetration of less than 1%.Per Test 5.b in Table 2 at a relativehumidity of 70% for a methyliodide penetration of less than0.175%.aThe activated carbon, when new, should meet the specifications of regulatory position C.3.i of this guide.bMuttiple beds, e.g., two 2-inch beds in series, should be treated as a single bed of aggregate depth.eSee regulatory position C.6.b. for definition of representative sample. Testing should be performed (1) initially, (2) at least once peroperating cycle thereafter for systems maintained in a standby status or after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation, and (3) followingpainting, fire, or chemical release in any ventilation zone communicating with the system.1.52-11