ISPE HVAC翻译(part3)

6.1.8.4TerminalFiltration终端过滤器ThisleveloffiltrationusesHEPAfilterstypicallyatthesupplyairterminal,andassociatedwithcleanroomsclassifiedascleanerthanISO8.Aterminalfiltermayalsobeusedonreturn/exhaustairwhenprocessroomairiscontaminatedwithenvironmentallysensitiveparticulates(hazardousairbornematerials).Thesefiltersshouldhaveasiliconegelsealonthedownstreamsideofthefiltertoformapositivesealtoeliminateairbypassaroundthefilterperimeter.Permanentupstreamanddownstreammediaprotectivescreens(mediaguards)shouldbeincludedtopreventphysicaldamagetothemedia.IndividualHEPAfiltersinfilterbanksshouldbeabletobereplacedwithoutdisruptionofadjacentfilters.H14(99.995%@MPPS)efficientfilterisrecommended.此过滤等级常常使用高效过滤器，位于供风终端，房间洁净等级高于ISO8。当工艺房间的空气含环境敏感颗粒（有害空气物质）时，可能在回风/抽风处使用终端过滤器。此类过滤器应在过滤器下端面配有硅胶密封条以形成完全密封，消除过滤器四周的空气旁路。应该安装上下游过滤介质保护屏以防止介质的有形损坏。单个高效过滤器应能在不影响临近过滤器的条件下别更换。推荐使用H14(99.995%@MPPS)过滤器。TerminalAirFilterModulesareconstructedaseitherasingleormultipleHEPAfilterhousingstructure.Theyarepositionedattheentry(ceiling)oftheroomandprovidecleanairintothespace.终端空气过滤模板是由单个或多个高效过滤器组构成。过滤器置于室内进口（天花板），向室内提供洁净空气。Aterminalmoduleisusuallyintendedtohouseasinglefilter.Themoduleshouldbecompletewithinsulatedhousing(ifambientconditionssurroundingthemodulewouldresultincondensation),filter,testports,grille,trim,andhardware.Thebodyofthemoduleissolidlyconstructedofcleanablerigidmaterial(suchasstainlesssteeloraluminum)withtheexposedtrimbeingstainlesssteel.Itshouldbedesignedforroomsidefilterreplacement.终端过滤模板常常使用单个过滤器。终端过滤模板应使用完全绝热的外壳（如果模板接触外部环境，那么将导致冷凝），过滤器，测试端口，切边，滤芯，器具全置于外壳内。过滤模板主体由可清洁的刚性物质构成（如不锈钢或金属铝），暴露的切边用不锈钢。其应设计成房间一侧过滤器更换。Aterminalplenummoduleorunidirectionalairflowunit(UDForUAF)isintendedtohouseatleast2filterstodistributeunidirectionalairflowoveraspecificarea(typicallyanISO5classificationspace).Theyarefabricatedstructuralplenumsthathousetheairinletopening,filters,dampers,challengedispersionmanifold,testports,optionalsprinklersystem,andanintegralgridforsupportofgelsealfilledframedfilters,flushmountedlightingandperforatedgrill.终端集气模板或单方向气流单元至少使用2个过滤器以向特定的区域（常为ISO5洁净等级）散布单向气流。他们由多个单元在一个外壳中集合而成，包括空气进口孔，过滤器，风门，分散支管，测试端口，可选择性的自动灭火系统，为支持硅胶密封条填满过滤器框架用的整体栅格，充足的照明设施，穿孔栅格。Bag-in/Bag-outHousingisasideservicedfilterhousingdesignedtomeettheairfiltrationneedsofhandlingdangerousortoxicbiological,radiological,cytotoxicorcarcinogenicmaterials.Itpreventshazardousairbornematerialsfromescapingintothesurroundingatmosphere.Itistypicallypositionedattheperimeter(nearfloor)oftheroomwherethematerialisgenerated.袋进袋出外壳是一种单面运行的过滤器外壳，其用于处理危险或有毒生物、放射性物质、细胞毒素、致癌性物质。它阻止有害空气物质逃逸到周围大气中。常位于房间四周接近有害物质产生处。Thehousingisconstructedofstainlesssteel,shouldhavezeroleakage,andusesacontrolbarriertoisolatespersonnelfromhazardousmaterialswhenchange-outoftheHEPAfilterisneeded.Thehousingshouldhaveasilicongelsealandbeadequatelyreinforcedtowithstandanegativeorpositivepressureof15w.g.(3.75kPa).外壳由不锈钢构成，当需要更换高效过滤器时，外壳应该零泄漏，使用控制栅栏以阻止有害物质接近人员。外壳应该有硅胶密封条，足够保持15”w.g.(3.75kPa)的正压或负压。6.1.8.5AvoidingproblemswithHEPAfilterperformance:避免高效过滤器性能问题TherearesomespecificissueswithHEPAfiltersthathavebeenobservedinrecentyearsinpharmaceuticalcleanroomswhichrequiresomeattentiontodetailinordertoavoid.Twooftheseare近年来，在制药洁净室发现了一些特殊的高效过滤器问题，这些问题需要给与特别的细节关注。其中两个问题是：HEPAfiltergelsealdegradation,and高效过滤器凝胶封条降解HEPAfilterbleedthrough.高效过滤器过滤渗漏HEPAfiltergelsealdegradation-高效过滤器凝胶密封条降解——Degradationofgelsealshasbeenobservedincleanroomapplicationsassilicone(siloxane)gelwhichappearstoreverttoaliquidstateandbeginsdrippingoutofthegeltrack.Thisissometimesaccompaniedbyacolorchange,suchasfadingtoaclearortranslucentappearance.Thismostoftendoesnotresultinanobservedintegrityfailureofthefilter,butdoespresentobvioussterilityandsafetyissues.Studiesproblemhavedeterminedthatthisfailureisduetothemigrationofunbondedpolymercomponentsoutofthegelmatrix,formingaslimyliquidonthesurfaceofthegel.Factorswhichcontributetothisinclude:凝胶密封条降解在洁净室使用硅基有机树脂胶的情形中发现，密封条会变为液态，滴下凝胶。有时，降解是由颜色变化显示，如褪色至透明或半透明状。这个问题常常不会导致过滤器完整性失效，但带来明显的无菌问题和安全问题。有关研究表明，密封条降解是由于未键合的聚合物转移出凝胶整体结构，在凝胶表面形成黏性的液态物质。影响这一现象出现的因素包括：Crosslinkingofthegelcomponents凝胶组分的交叉耦合Themorecompletethecrosslinking,thelessunbondedpolymertomigratetothesurfaceThespecificgeltypeandthemixing(ratioofcomponents,environmentalconditions,timetocompletethereaction,etc.)arekeytoamountofcrosslinking.交叉耦合越完全，未键合聚合物就越少，移动至凝胶表面的物质就越少。凝胶类型和混合程度（凝胶组分比，环境条件，完全反应的时间等）是影响交叉耦合数量的关键。Molecularweightofthegel凝胶分子量HighermolecularweightreducesthediffusionandmigrationofunbondedpolymersNarrowweightdistributionisdesiredatthehighermolecularweights分子量高有助于减少未键合聚合物的分散和移动。在较高分子量条件下，需要限制重量分布。Certainchallengeaerosols(PAO,DOP,etc.)acceleratetherateofunbondedpolymerdiffusion某些喷雾测试（PAO聚α烯烃,DOP酞酸二辛酯等）会加速未键合聚合物的分散速率。Actsasasolvent,increasingmigrationofunbondedpolymerstothesurfaceItdoesnotappearthattypicalpharmacleanroomcleaningandsanitizingagents(suchasbleach,hydrogenperoxide,etc.)affecttherateofunbondedpolymerdiffusion.可作为溶剂，加速未键合聚合物移动至表面。典型的制药洁净室的清洁消毒试剂（如：漂白剂，双氧水等）是否会影响未键合聚合物的分散还不清楚。Itisalsorecommendedthatmiterjointsandpenet