EE XX OO MM AA RR SS
ExoMars: Planetary Protection Requirements & Implementation
Presentation to the NASA PPS G. Kminek and the ExoMars Project Team 1 20 January 2011, NASA-HQ Programme Building Blocks E X OO M A R S
•• EESASA andand NANASSAA havhavee agreedagreed toto embarkembark onon aa jojointint MarsMars roboticrobotic exexplorationploration programme:programme:
InitialInitial missionsmissions havehave beenbeen dedefinedfined forfor thethe 20162016 (January)(January) andand 20182018 launchlaunch opportuniopportunities;ties;
MissionsMissions forfor 20202020 andand beyondbeyond areare inin aa planningplanning stage;stage;
TheThe jointjoint programme’sprogramme’s ultiultimatemate objectiveobjective isis anan internationalinternational MarsMars SampleSample ReturnReturn mimission.ssion.
2016 ESA-led mission Launcher: NASA – Atlas V-431 Orbiter: ESA Payload: NASA-ESA EDL Demo: ESA
2018 NASA-led mission Launcher: NASA – Atlas V-531 Cruise & EDL: NASA Rover 1: ESA Payload: ESA-NASA Rover 2: NASA
2 2016 Mission Objectives E X OO M A R S
TECHNTECHNOLOGYOLOGY OBJECTIVEOBJECTIVE
Entry,Entry, Descent,Descent, andand LandingLanding (EDL)(EDL) ofof aa payloadpayload onon thethe surfacesurface ofof Mars.Mars. 20162016
SCIENTIFICSCIENTIFIC OBJECTIVEOBJECTIVE
ToTo studystudy MartianMartian atmosphericatmospheric tracetrace gasesgases andand theirtheir sources.sources.
➟ UseUse ofof aerobrakingaerobraking toto achieveachieve sciencescience orbiorbit.t. ProvideProvide datadata relayrelay servicesservices foforr landedlanded missionsmissions untiluntil 2022.2022.
3 2016 Trace Gas Orbiter Payload E X OO M A R S
PRIORITISED GOALS INSTRUMENTS
1. Detect a broad suite of atmospheric trace gases MATMOS US, CAN H/W and key isotopes with high sensitivity. (ppt) B, F, RUS Science
2. Map their spatial and temporal variability NOMAD B, E, I, UK with high sensitivity. (10–1 ppb) USA, CAN
3. Determine basic atmospheric state by EMCS USA, UK characterising P, T, winds, dust and water (P, T, dust, ices, H2 O) F aerosol circulation patterns. MAGIE USA (Full hemisphere WAC) B, F, RUS
4. Image surface features possibly related to HiSCI USA, CH trace gas sources and sinks. (HRC 2 m/pixel) UK, I, D, F
ExcellentExcellent coveragecoverage ofof high-priorityhigh-priority objectives.objectives.
4 2016EDL EDL Demonstration Module (EDM) Module E X OO M A R S
EDMEDM
AA EuropeanEuropean technologytechnology demdemonstratoronstrator forfor landinglanding medimedium-largeum-large payloadspayloads onon Mars;Mars;
ProvidesProvides aa limited,limited, butbut usefuluseful meansmeans toto conductconduct scientificscientific measurementsmeasurements duringduring ththee dustdust stormstorm season.season.
EDMEDM PAYLOADPAYLOAD
IntegratedIntegrated payloadpayload massmass estimate:estimate: 33 kg;kg;
LifetiLifetime:me: 44 solssols;;
DatDataa:: 11 passpass ofof 5050 MMbbitits.s.
5 2018 ExoMars RM Objectives E X OO M A R S
TECHNTECHNOLOGYOLOGY OBJECTIVESOBJECTIVES SurfaceSurface mobilitymobility withwith aa roverrover ((havinghaving severalseveral kikilometreslometres range);range); AccessAccess toto thethe subssubsurfaceurface toto acquireacquire samplessamples (with(with aa drill,drill, downdown toto 2-m2-m 20182018 depth);depth); SampleSample acquisition,acquisition, preparatipreparation,on, distridistribution,bution, andand analysianalysis.s. SCIENTIFICSCIENTIFIC OBJECTIVESOBJECTIVES ToTo searchsearch forfor signssigns ofof papastst andand presentpresent lifelife onon Mars;Mars; ToTo chacharraaccteteriserise ththee waterwater//ssubsubsurfaceurface environmentenvironment asas aa functionfunction ofof depdepthth inin thethe shallowshallow subsurface.subsurface.
6 2018 Pasteur Payload E X OO M A R S
Panoramic camera system
HRCHRC
xx
WAC WAC Two Wide Angle Cameras (WAC): Color, stereo, 34° FOV One High-Resolution Camera (HRC): Color, 5° FOV
~3~3-m-m pene penetratrationtion, ,w withith ~2 ~2-cm-cm re resosolulutiotionn (depend(dependss on on s subsuubsurrfafacece E EMM p prropeopertierties)s)
0 0 Aeolian deposits
Sedimentary filling SSppeecctratral lrange range: : 0 0.4–2.4–2.4.4 μ μm,m, (m) (ns) SSaampmplingling res resoolulutiontion: :20 20 nm nm Ground-Penetrating Radar 10 100 AnAnalyticalalytical L Laabb 0 Distance7 (m) 30 2018 Pasteur Payload E X OO M A R S
Use mineralogical + imaging information from μΩIR Imaging IR spectrometer, 256 x 256 pixels, 20-μm/pixel resolution, to identify targets for Raman and MOMA LDMS. 0.85–2.6 μm spectral range, 500 steps
e.g. search 1.9 μm + 2.3 μm bands RocRockk Crusher Crusher Sample
Powder Drill System
Mineralogy 1) Survey 2) Detailed Analysis
identify μΩμΩ IRIR targets Organics
RamRamaann
MOMOMAMA LDMSLDMS LDMSLDMS DetailDetaileded SurvSurveeyy ++ GCMS μΩIR = 20 μm GCMS Raman = 50 μm XRD = 1 cm XRD/XRFXRD/XRF LDMS = 100 μm
Raman: spectral shift range 200–3800 cm–1 LDMS = Laser-Desorption Mass Spectrometry, Spectral resolution ~6 cm–1 GCMS = Gas-Chromatograph Mass Spectrometry 8 PlanetaryP ProtectionP Category Category E X OO M A R S
EstablisEstablishinghing PPllanetaryanetary PPrrotectionotection CategorCategoryy andand RequiremRequirementsents
ESAESA isis mimissionssion leadlead forfor thethe 20162016 missmissionion andand hencehence responsibleresponsible forfor isissuingsuing thethe planetaryplanetary protectionprotection categorycategory andand thethe associatedassociated requiremrequirementsents andand verifyingverifying theirtheir correctcorrect imimplementation,plementation, inin accordanceaccordance withwith thethe ESAESA andand NASANASA PlanetaryPlanetary ProtectionProtection Policies.Policies.
NASANASA isis missionmission leadlead forfor thethe 20182018 missionmission andand hencehence reresponsiblesponsible forfor issuingissuing tthehe planetaryplanetary protectionprotection categorycategory andand thethe associatedassociated requiremrequirementsents andand verifyingverifying theirtheir correctcorrect imimplementation,plementation, inin accordanceaccordance withwith thethe ESAESA andand NASANASA PlanetaryPlanetary ProtectionProtection Policies.Policies.
DueDue toto thethe launchlaunch ofof thethe missionmission fromfrom aa NASANASA facilityfacility andand thethe larglargee contributioncontribution ofof USUS andand NASANASA hardwarehardware (e.g.,(e.g., launcher,launcher, paylpayload),oad), thethe NASANASA PPOPPO hashas beenbeen involvedinvolved inin thethe categocategorizationrization andand establishmentestablishment ofof thethe associassociatedated requrequirementsirements andand isis stillstill involvedinvolved inin rereviewiviewingng theirtheir correctcorrect implementationimplementation (e.g.,(e.g., PDPDR),R), inin accordanceaccordance withwith NASNASAA NPRNPR 8020.12.8020.12. Categories,Categories, toptop levellevel requirequirementrementss andand implementationimplementation approachapproach havhavee beenbeen presentedpresented toto thethe COSPARCOSPAR PlanetaryPlanetary ProtectionProtection PanelPanel inin 2010.2010. PPllanetaryanetary ProtectionProtection CategorCategoriesies
ExoMarsExoMars TGOTGO isis plplanetaryanetary prprotectionotection categorycategory IIIIII
ExoMarsExoMars EDMEDM isis plplanetaryanetary protprotectionection categorycategory IVaIVa ((nono accessaccess toto MarsMars specialspecial rregionsegions andand nono lifelife detectiondetection capability)capability)
NoNo planetaryplanetary protectionprotection catecategorygory hashas beenbeen yetyet assignedassigned byby NASANASA toto thethe 20182018 missionmission bubutt basedbased onon thethe cachingcaching ofof samplessamples forfor aa futurefuture reretuturnrn missionmission aa planeplanetarytary proprottecectiotionn categorycategory V,V, restrictedrestricted EartEarthh return,return, withwith equivalequivalentent IVbIVb requirementsrequirements forfor thethe outboundoutbound lelegg isis expectedexpected inin complicomplianceance withwith thethe COSPARCOSPAR planetaryplanetary protprotectionection policy;policy; thisthis wouldwould alsoalso bebe compatiblecompatible withwith thethe lilfeife detectidetectionon objectiobjectivesves ofof thethe 9 ExoMarsExoMars roverrover 2016 PP Requirements E X OO M A R S
ControlledControlled envenvironmentsironments UseUse ofof ISISOO standardsstandards forfor cleanroomcleanroom specspec (14644-1)(14644-1) andand controlcontrol (14644-2)(14644-2) StandardStandard toto bebe usedused forfor biobbioburdenurden controlcontrol inin clcleanroomseanrooms ECSECSS-Q-ST-70-58S-Q-ST-70-58 RequirementsRequirements andand proceduresprocedures sisimilarmilar toto NASANASA MarsMars missionsmissions CompatibilityCompatibility withwith bioburdbioburdenen assassaysays andand alcalcoholohol wipeswipes StandardStandard toto bebe usedused forfor bioburdenbioburden assayassay ECECSS-Q-ST-70-55SS-Q-ST-70-55 BBioburdenioburden assassessmentessment AllAll bioburdenbioburden constraintsconstraints havehave toto bebe verifiedverified pre-launchpre-launch TotalTotal bioburdenbioburden ofof thethe flightflight systemsystem hashas toto bebe assessedassessed OrganicOrganic invinventoryentory andand ararchivechive DeliveryDelivery ofof archivearchive withwith flightflight HH/W/W toto missionmission leadlead (ESA(ESA)) forfor storagestorage ImpactImpact probabilitprobabilityy constraintconstraint forfor launclauncherher -4 ImpactImpact probability:probability: ≤≤1x101x10 -4 untiluntil 5050 yearsyears afterafter launchlaunch TaskTask forfor llaunchaunch serviceservice proviproviderder
BBiioburdenoburden controlcontrol forfor thethe S/CS/C stackstack (TGO(TGO andand EEDDM)/TGOM)/TGO 5 TotalTotal bioburden:bioburden: ≤≤5x105x10 5 spores,spores, OROR -2 -2 ImpactImpact probability:probability: ≤≤1x101x10 -2 untiluntil 2020 yearsyears afterafter launch,launch, andand ≤≤5x105x10 -2 forfor thethe titimeme periperiodod 2020-50-50 yearsyears afterafter launchlaunch BBiioburdenoburden controlcontrol forfor thethe EDMEDM 5 TotalTotal bioburden:bioburden: ≤≤5x105x10 5 spores,spores, andand 5 SurfaceSurface bioburden:bioburden: ≤≤3x103x10 5 sporspores,es, andand 2 AverageAverage bioburden:bioburden: ≤≤300300 spores/mspores/m2
10 2018 RM PP Requirements E X OO M A R S
ControlledControlled envenvironmentsironments UseUse ofof ISISOO standardsstandards forfor cleanroomcleanroom specspec (14644-1)(14644-1) andand controlcontrol (14644-2)(14644-2) StandardStandard toto bebe usedused forfor biobbioburdenurden controlcontrol inin clcleanroomseanrooms ECSECSS-Q-ST-70-58S-Q-ST-70-58 AdditionalAdditional standardsstandards usedused forfor momolecularlecular contamicontaminationnation controlcontrol CompatibilityCompatibility withwith bioburdbioburdenen assassaysays andand alcalcoholohol wipeswipes StandardStandard toto bebe usedused forfor bioburdenbioburden assayassay ECECSS-Q-ST-70-55SS-Q-ST-70-55 BBioburdenioburden assassessmentessment AllAll bioburdenbioburden constraintsconstraints havehave toto bebe verifiedverified pre-launchpre-launch TotalTotal bioburdenbioburden ofof thethe RRM,M, includingincluding HHEPAEPA filterfilter isolatedisolated volumes,volumes, hashas toto bebe assessedassessed OrganicOrganic invinventoryentory andand ararchivechive DeliveryDelivery ofof archivearchive withwith flightflight HH/W/W toto missionmission leadlead (NAS(NASA)A) forfor storagestorage
BBiioburdenoburden controlcontrol forfor thethe RMRM 4 † SurfaceSurface bioburden:bioburden: ≤≤2x102x10 4 sporesspores†,, andand 2 AverageAverage bioburden:bioburden: ≤≤300300 spores/mspores/m2,, andand SampleSample pathwaypathway contaminationcontamination levellevel (bio(biologicallogical andand molecular):molecular): dridrivvenen byby thethe particulparticularar life-detectionlife-detection experimentsexperiments (MOMA(MOMA andand LMC),LMC), i.e.i.e. stersterileile andand << 5050 ngng TOCTOC//gg ofof samplesample delivdeliveredered toto thethe lifelife detectidetectionon experiexperimmentsents
† 4 †DrivingDriving requi requirement,rement, 1.6 1.6xx10104spore spore allo allocaticationon for for 2 deliverydelivery to to ES ESAA can can be be met met w withith ~200 ~200 sp spores/mores/m2 averaaveragege bio biobbuurrdeden,n, like like for for MER MER and and MSL MSL 11 2016 PP Implementation E X OO M A R S
ImportantImportant aspectsaspects toto considerconsider LaunchLaunch stackstack (T(TGOGO ++ EDM)EDM) isis fifirstrst largelarge stackstack afterafter VikingViking affectsaffects probabilprobabilityity ofof impactimpact assessmentassessment andand rerecontaminaticontaminationon potentialpotential TGOTGO isis usingusing aerobrakingaerobraking toto achieveachieve finalfinal sciencescience orbitorbit affectsaffects probabilityprobability ofof impactimpact assessmentassessment
CleanroomCleanroom assemblyassembly ISOISO 88 forfor generalgeneral OPsOPs ((e.g.,e.g., TGO)TGO) andand ISISOO 77 forfor bioburdenbioburden controlledcontrolled OPOPss ((e.g.,e.g., EDEDM)M) BioburdenBioburden controlledcontrolled OPsOPs aandnd needneed foforr microbiologicalmicrobiological lablab atat KSKSCC Trade-offTrade-off forfor S/CS/C stack/Tstack/TGOGO bioburdenbioburden controlcontrol approacapproachh ProbabilityProbability ofof impactimpact analysianalysiss forfor S/CS/C stacstackk andand forfor thethe TGOTGO postpost EDMEDM separationseparation DependingDepending onon result,result, bibioburdenoburden controlcontrol mightmight bebe necessarynecessary forfor TTGGOO † Break-up/burn-upBreak-up/burn-up ofof TTGOGO couldcould bebe usedused asas bioburdenbioburden reductionreduction processprocess (e.g.,(e.g., likelike MRO)MRO)† RecRecoontaminationntamination preventionprevention ofof EDMEDM backsbackshieldhield EDMEDM backshieldbackshield temperaturestemperatures duringduring entryentry notnot sufficisufficientent toto claimclaim aadequatedequate bioburdenbioburden reductionreduction bioburdenbioburden onon backshieldbackshield hashas toto bebe accountedaccounted for,for, inclincludinguding launchlaunch rreecontcontamaminatinationion 2 ExternalExternal TGOTGO && launcherlauncher fairingfairing averageaverage bioburdenbioburden ≤≤10001000 spores/mspores/m2 RecRecoontaminationntamination preventionprevention ofof EDMEDM interiorinterior ContaminationContamination sources:sources: exteexternalrnal elementselements duringduring testintesting,g, storagestorage aandnd transporttransport (contingency),(contingency), exterexternalnal TTGGOO andand launcherlauncher faringfaring duringduring launchlaunch UseUse ofof HHEPAEPA filterfilter atat aeroshellaeroshell levellevel UsUsee ofof pre-pre- andand postpost launclaunchh procprocessesseess forfor bioburdenbioburden reducreducttionion UsedUsed forfor e.g.,e.g., CFRCFRPPss (polymerization)(polymerization) andand heatheat shieldshield tilestiles (bake-out)(bake-out) 3 † UsedUsed forfor pyro-andpyro-and mortarmortar cacartridgesrtridges wwithith 3030 spores/cmspores/cm3 allocationallocation forfor uunburnednburned residueresidue† ††Deviation of pre-launch Deviation of pre-launch Not always possible, e.g., parachute vacuum stripping before folding reqrequuiremirementent Not always possible, e.g., parachute vacuum stripping before folding 12 2018 RM PP Implementation E X OO M A R S
ImportantImportant aspectaspect toto consconsiderider RecontaminationRecontamination ofof EExxoMarsoMars RMRM afterafter deliverydelivery toto NASANASA commitcommit onon deldeliveryivery andand begin-of-operationbegin-of-operation bioburdenbioburden andand recontaminationrecontamination levelslevels
CleanroomCleanroom assemblyassembly ISOISO 88 forfor generalgeneral Ops,Ops, ISISOO 77 forfor bibioburdenoburden controlledcontrolled OPOPss ((e.g.,e.g., afterafter deliverydelivery toto NASA),NASA), ISOISO 3,3, ISOISO AMAMCC--99 forfor elementselements inin thethe samplesample pathwaypathway (e.g.,(e.g., partsparts ofof MOMAMOMA P/L,P/L, drildrill l andand samplesample distributiondistribution system)system) BioburdenBioburden controlledcontrolled OPsOPs aandnd needneed foforr microbiologicalmicrobiological lablab atat KSKSCC ControlControl ofof hardwarehardware ususeded forfor thethe acquisacquisiition,tion, transtransportport andand analyanalyssiiss ofof thethe samplessamples UseUse ofof bibiologicalological andand molecularmolecular barribarrierers,s, inin particularparticular aa pressurizedpressurized andand sealedsealed UlUltra-Clean-Zonetra-Clean-Zone (U(UCZ)CZ) UseUse ooff VVEERYRY cleacleann (e(e.g.g.,., sisimilarmilar toto VViking)iking) andand sterilesterile samplesample pathwaypathway AssessmentAssessment ofof re-contaminationre-contamination potenpotentialtial duringduring samplesample acquisitionacquisition andand transporttransport AvoidingAvoiding contaminationcontamination sourcessources inin thethe samplesample pathwaypathway thatthat couldcould compromisecompromise life-detectionlife-detection experimentsexperiments AssessmentAssessment ofof molecularmolecular contaminatcontaminationion sourcessources inin thethe samplesample pathwaypathway thatthat cannotcannot bebe avoiavoided,ded, includingincluding cleaningcleaning agentsagents UseUse ofof blblanksanks duriduringng operationoperation onon MarsMars ControlControl ofof RMRM internalinternal envirenvironmonmentent (i.e.(i.e. servserviceice modulemodule andand partpart ofof payload)payload) † IsolationIsolation withwith H14H14 HEPAHEPA filtersfilters† ConditionCondition forfor useuse ofof HEPAHEPA isolatisolation:ion: averageaverage bibioburdenoburden ofof HEPAHEPA 2 isolatedisolated volumesvolumes ≤≤10001000 spores/mspores/m2 † †DeviationDeviation of of p prre-le-launaunchch UsedUsed forfor H/WH/W outsioutsidede thethe UUCCZZ andand ininsideside thethe bathtubbathtub anandd onon electronicelectronic reqrequuiremirementent modules outside the RM (e.g., PanCam, Ma_Miss electronics) modules outside13 the RM (e.g., PanCam, Ma_Miss electronics) PP Training E X OO M A R S
DifferentDifferent levelslevels ofof trainingtraining aapplypply dependingdepending onon thethe individualindividual taskstasks
LevelLevel 0:0: EnsuringEnsuring aa commoncommon understandingunderstanding throughoutthroughout thethe projectproject ofof thethe reasonsreasons forfor planetaryplanetary protection,protection, andand whwhyy itit isis imimportantportant toto everyone.everyone. ToTo bebe attendedattended byby allall iinvolvednvolved personnelpersonnel iinn thethe projproject.ect.
LevelLevel 1:1: IntendedIntended forfor anyany ofof thethe workforcworkforcee NOTNOT requiredrequired toto workwork inin bioburdenbioburden controlcontrol areaarea bubutt neverthelneverthelessess whosewhose acactionstions maymay affectaffect workwork insideinside thethe bioburdenbioburden controlledcontrolled area,area, e.g.,e.g., somesome subcontractors,subcontractors, sstocktock control,control, goodsgoods inwinward.ard. LevelLevel 2:2: IntendedIntended forfor anyany ofof thethe workfoworkforcerce workingworking insideinside bioburdenbioburden controlledcontrolled areas,areas, includingincluding clcleanrooeanroomm cleaners,cleaners, maintenancemaintenance workers,workers, ATLOATLO personnel.personnel. LevelLevel 3:3: IntendedIntended forfor planetaryplanetary protecprotectiontion supervisorssupervisors –– personnelpersonnel monitoringmonitoring thethe operationoperation ofof thethe bioburdenbioburden controlledcontrolled facilityfacility andand anyany activitiesactivities ininside.side.
ProgressProgress
TrainingTraining organizedorganized byby ExoMarsExoMars PrimePrime ContractorContractor (Thales(Thales AAlenialenia SSpace-Italy,pace-Italy, TAS-TAS-I)I) currentcurrentlyly covercoverss levellevel 00 andand 1;1; approx.approx. 350350 participantsparticipants soso farfar sisincence 20082008
ESA/NASAESA/NASA trainingtraining coursecoursess areare creditedcredited forfor levellevel 00 andand 1;1; 140140 participarticipantspants soso farfar sincesince 20032003
TrainingTraining hashas beenbeen attendedattended byby alalmostmost allall ESAESA andand TAS-ITAS-I projectproject disciplinediscipline managersmanagers andand engineersengineers 14 Status E X OO M A R S
GenerGeneralal ExExoMarsoMars programprogram statusstatus SuccessfullySuccessfully passedpassed systesystem-PDRm-PDR inin DecemberDecember 20102010 PricePrice proposalproposal forfor phasesphases CC/D/E1/D/E1 expectedexpected inin FFebruaryebruary 20112011 Kick-offKick-off forfor phasephase C/DC/D expectedexpected inin AAprilpril 20112011 ESA-NASAESA-NASA MemorandumMemorandum ofof UnderstandingUnderstanding concconcerningerning cooperationcooperation onon thethe roboticrobotic explorationexploration ofof MarsMars currentcurrentlyly inin finalfinal draftdraft versionversion PayPayloadload statusstatus TGOTGO (2016)(2016) payloadpayload selectedselected basedbased onon jointjoint ESA-NASAESA-NASA AOAO EDMEDM (2016)(2016) payloadpayload jointjoint ESA-NASAESA-NASA AOAO issuedissued NovemberNovember 2010,2010, proposalproposalss duedue 11stst March,March, selectionselection expectedexpected inin JuneJune 20112011 RoverRover (2018)(2018) PPasteurasteur PayloadPayload selectedselected
PPllanetaryanetary protectionprotection statusstatus
CategoryCategory andand requirequirementsrements havehave beenbeen coordinatedcoordinated withwith COSPARCOSPAR andand NASANASA PlanetaryPlanetary ProtectionProtection PlanPlan waswas reviewedreviewed duringduring PDRPDR andand finalfinal versiversionon expectedexpected inin MarchMarch 20112011 VerificationVerification methodsmethods ofof requirequirementsrements agreedagreed BioburdenBioburden reservereserve forfor 20162016 mimissionssion (TGO(TGO ++ EEDDM)M) atat PPDR:DR: ~30%~30% atat TASTAS--II level;level; 10%10% ofof thisthis reservereserve willwill bebe allocatedallocated toto thethe flightflight system,system, keepingkeeping aa 20%20% bibioburdenoburden reservereserve atat TAS-ITAS-I levellevel untiluntil CDRCDR BioburdenBioburden reservereserve atat ESAESA levellevel willwill bebe kekeptpt untiluntil jointjoint operationoperation atat launchlaunch sisitete BioburdenBioburden reservereserve forfor 20182018 ExoMarsExoMars roverrover atat PPDR:DR: 15%15% atat TASTAS--II lelevel;vel; addiadditionaltional 20%20% atat ESAESA levellevel ExpectedExpected deviationsdeviations fromfrom requirementrequirementss havehave beenbeen identiidentifiedfied (u(usese ofof HEPAHEPA iissolatiolation,on, useuse ofof bioburdenbioburden reductionreduction post-launchpost-launch forfor explosivexplosivee cartridgescartridges andand heatheat shishieeld)ld) cconsionsidereddered acceptableacceptable duringduring PDPDRR
15