1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS ISO 18923:2000 ICS 35.
2、220.22; 37.040.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Imaging materials Polyester-base magnetic tape Storage practicesThis British Standard, having been prepared under the direction of the Consumer Products and Services Sector Committee, was published under the aut
3、hority of the Standards Committee and comes into effect on 15 August 2000 BSI 08-2000 ISBN 0 580 36266 3 BS ISO 18923:2000 Amendments issued since publication Amd. No. Date Comments National foreword This British Standard reproduces verbatim ISO 18923:2000 and implements it as the UK national standa
4、rd. The UK participation in its preparation was entrusted to Technical Committee CPW/42, Photography, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and k
5、eep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications r
6、eferred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of
7、 a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a bla
8、nk page, pages 1 to 17 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.Referencenumber ISO18923:2000(E) INTERNATIONAL STANDARD ISO 18923 Firstedition 2000-06-01 ImagingmaterialsPolyester-base magnetictapeStoragepractices Matriaux pour
9、 image Bande magntique base de polyester Pratiques demmagasinageISO18923:2000(E) ii ISO18923:2000(E)iii Contents Page Forewordv Introductionvi 1 Scope1 2 Normativereferences1 3 Termsanddefinitions.2 4 Environmentalconditions.5 5 Materials.7 6 Enclosures7 7 Preparation.8 8 Storagehousing.9 9 Storager
10、ooms9 10 Fire-protectivestorage10 11 Identification,inspection,andcleaning10 AnnexA(informative)NumberingsystemforrelatedInternationalStandards.11 AnnexB(informative)Stabilityofcellulosetriacetatebase12 AnnexC(informative)Distinctionbetweenmastertapesandworkcopies13 AnnexD(informative)Temperature/re
11、lativehumidityrelationship14 AnnexE(informative)Temperatureandhumidityacclimatization.15 Bibliography17 Table1Maximumtemperatureandrelativehumidityforstorage.6ISO18923:2000(E) iv Foreword ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISO memberbod
12、ies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnical committees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhas therighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmental,in liaisonwithISO,alsot
13、akepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnical Commission(IEC)onallmattersofelectrotechnicalstandardization. InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part3. DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculated
14、tothememberbodiesforvoting. PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote. AttentionisdrawntothepossibilitythatsomeoftheelementsofthisInternationalStandardmaybethesubjectof patentrights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights
15、. InternationalStandardISO18923waspreparedbyTechnicalCommitteeISO/TC42, Photography. ThisInternationalStandardisoneofaseriesofstandardsdealingwiththephysicalpropertiesandstabilityof imagingmaterials.TofacilitateidentificationoftheseInternationalStandards,theyareassignedanumberwithin theblockfrom1890
16、0to18999(seeannexA). AnnexesAtoEofthisInternationalStandardareforinformationonly.ISO18923:2000(E)v Introduction Magnetictapeisanimportantmaterialinthecapturingofinformationandhashadwidespreaduseinaudio,video, andcomputerapplicationsoverthepast60years.Preservationofthisinformationisbecomingofincreasi
17、ng concerntosociety,particularlyastherecordedinformationbecomesolderandfrequentlyofgreatervalueto libraries,archives,museums,governmentagencies,andcommercialorganizations.Magnetictapeisalsowidely usedbyindividualconsumerstopreserverecordsofpersonalorentertainmentvalue. Theretrievabilityoftheinformat
18、iononmagnetictapeisdependentuponthatofthecompletemagneticsystem. Thisincludesthestabilityofthetapeitself,theequipmentonwhichitisrunand,insomesystems,uponthe necessarysoftware.Itisrecognizedthattaperecordswilleventuallyhavetobecopiedortransferredtoanother materialwhenthesystembecomesobsolete.Neverthe
19、less,itisadvantageoustoprolongthetapelifesothatthe materialdoesnotbecomethecontrollingfactor. Althoughtherehavebeenmanystudiesoftapestability,InternationalStandardsdonotexistagainstwhichtapelife canbeevaluated.Likewise,InternationalStandardsarenotavailableonthelifeexpectancyofhardwareandthe problems
20、associatedwithhardwarewearingoutorbecomingobsolete.Therefore,thebestapproachfortapeusers istostoremagnetictapeunderconditionsthatwillextenditslifeandtohandletapesothatitwillnotbesubjected tostressandundergophysicalbreakdownduringuse.ThisInternationalStandardaddressestheconcernsof storage. Amajorcomp
21、onentofmagnetictapeistheplasticbase.Earlyaudio-magnetictapewasmanufacturedonavariety ofbasematerials,includingpaper,variousvinylesters,andcelluloseesters.Afterextendedstorage,orstorage underadverseconditions,thecellulose-triacetatebasedecomposesandproducesaceticacid(seeinformative annexB).However,si
22、ncethe1960s,magnetictapehasbeencoatedontoapolyesterbasethathasexcellentlong- termstability.ThisInternationalStandardwasdevelopedspecificallyforpolyester-basetapes.However,itisalso applicabletothestorageoftriacetate-basetapeseventhoughthetriacetatebaseisnotasstable. Thesecondcomponentofmagnetictapeis
23、theoxide(ormetalparticle)binderlayerwhichdeterminesthe magneticcharacteristics.Amagneticcharacteristicofimportanceintheagingbehaviouroftapeisthedevelopment ofprint-throughofanalogtape.However,bothresearchandusehaveclearlydemonstratedthatthecritical concernsareprimarilychangesinphysicalproperties,not
24、thelossofmagneticcharacteristics.Uponuseand aging,theremaybechangesinthefrictionproperties,abrasivity,binder-baseadhesion,andbindercohesionthat renderthetapeunusable.Manyofthesechangesoccurasaresultofbinderdegradation.Unfortunately,theuser hasnopracticalmeansofdeterminingthestabilityofthecompositeta
25、peandmustrelyonthestudiesofthe manufacturer. Regardlessoftheinherentstabilityofthebinderlayer,itisknownthatgoodstorageconditionswillextendthelifeof alltapes.Whileagoodstorageenvironmentcannotreverseallthedegradationthathasalreadyoccurred,itcan slowdownadditionaldeterioration. NOTE Somedegradedtapeca
26、nberenderedtemporarilyplayablebyavarietyofspecializedprocedures. TwostorageconditionsaredescribedinthisInternationalStandard.Medium-termstorageconditionsare recommendedfortapewithanexpectedusefullifeoftenyears,whileextended-termstorageconditionsare intendedfortapewithanexpectedlifeoffiftyyears.Theco
27、nditionsgiveninthisstoragerecommendationrepresent acompromisebetweenmaximizingthetapelife,considerationsofconvenience,andthecostofbuildingand maintainingastoragefacility.INTERNATIONALSTANDARD ISO18923:2000(E)1 ImagingmaterialsPolyester-basemagnetictapeStorage practices 1 Scope ThisInternationalStand
28、ardprovidesrecommendationsconcerningthestorageconditions,storagefacilities, enclosures,andinspectionforrecordedpolyester-basemagnetictapesinrollform.Itcoversanaloganddigital tapeandincludestapemadeforaudio,video,instrumentationandcomputeruse. ThisInternationalStandardisapplicabletomedium-termandexte
29、nded-termstorageofmagnetictapeasdefinedin 3.18and3.7andalsoisapplicabletomagnetic-taperecordsintendedasmastertapes,whichshouldnotbein frequentuse. Deviationsfromtheserecommendations,whetherbeforeorafterrecording,mayresultinshortenedlife expectancy.Forexample,adverseconditionsduringshipment,handling,
30、orusage. ThisInternationalStandardisnotapplicableto“work“or“use“copies(seeinformativeannexC). 2 Normativereferences Thefollowingnormativedocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof thisInternationalStandard.Fordatedreferences,subsequentamendmentsto,orrevisionsof
31、,anyofthese publicationsdonotapply.However,partiestoagreementsbasedonthisInternationalStandardareencouragedto investigatethepossibilityofapplyingthemostrecenteditionsofthenormativedocumentsindicatedbelow.For undatedreferences,thelatesteditionofthenormativedocumentreferredtoapplies.MembersofISOandIEC
32、 maintainregistersofcurrentlyvalidInternationalStandards. NFPA75-1995, Electronic computer/Data processing equipment. 1) NFPA90A-1996, Installation of air conditioning and ventilating systems. 1) NFPA232-1995, Protection of records. 1) ASHRAE, Equipment. 1988. 2) ASHRAE, Handbook of fundamentals. 19
33、88. 2) ASHRAE, Systems. 1987. 2) 1)AvailablefromtheNationalFireProtectionAssociation,1BatterymarchPark,P.O.Box9101,Quincy,MA02269-9101, USA. 2)AvailablefromtheAmericanSocietyofHeating,RefrigerationandAirConditioningEngineers,1791TullieCircle,NE Atlanta,GA30329,USA.ISO18923:2000(E) 2 3 Termsanddefini
34、tions ForthepurposesofthisInternationalStandard,thefollowingtermsanddefinitionsapply. 3.1 aperture window openingontheflangethatisusedtofacilitatethreadingofmagnetictapeonthehubandinspectionofthewind 3.2 base supportinarecordingmaterialonwhichthemagneticlayer(and,ifnecessary,thebacklayer)iscoated 3.
35、2.1 cellulose-acetatebase baseforrecordingmaterialscomposedmainlyofcelluloseestersofaceticacid 3.2.2 polyesterbase baseforrecordingmaterialscomposedmainlyofapolymerofethyleneglycolandterephthalicacid(alsoreferred toaspolyethyleneterephthalate),orapolymerofethyleneglycoland2,6naphthalenedicarboxylica
36、cid(also referredtoaspolyethylenenaphthalate) 3.3 cartridge housingforarollofrecordingmaterial,suchasphotographicfilmormagnetictape,attachedtoasinglehuborreel SEEcassette(3.4). 3.4 cassette housingforarollofrecordingmaterial,suchasphotographicfilmormagnetictape,whoseendsareattachedto twohubsorreels
37、3.5 container box,can,orcartonusedforstorageandshippingofrecordingmaterials EXAMPLE Theboxintowhichareel,cassette,cartridgeorshellisplacedisacontainer. NOTE Reels,cassettes,cartridgesorshellsarenotcontainers. 3.6 dew-point temperatureatwhichmoisturebeginstocondenseonasurface,correspondingtosaturatio
38、nforagivenabsolute humidity EXAMPLE Themorehumidtheair,thehigherthedew-pointtemperature. 3.7 extended-termstorageconditions storageconditionssuitableforthepreservationofinformationrecordedonthemajorityofmagnetictapesfor 50years 3.8 fire-protectivestorage facilitiesdesignedtoprotectrecordsagainstexce
39、ssivetemperatures,waterandotherfire-fightingagents,and steamdevelopedbyinsulationofsafesorcausedbytheextinguishingoffiresandcollapsingstructuresISO18923:2000(E)3 3.9 flange fixedorremovablecirculardisc,whichisconnectedtothehubtomakeareelforthepurposeofprotectingtheroll ofrecordingmaterial SEEreel(3.
40、21) 3.10 headsout configurationofmagnetictapestoredonitsreel,orinitscassette,suchthatthetapeispositionedtoplayfromthe beginningoftherecordedinformation 3.11 hub cylindricalobjectatthecentreofthetapereel,aroundwhichtherecordingmaterialiswound 3.12 leader flexibleplasticorpaperstripwhichcanbesplicedto
41、eitherendofarollofrecordingmaterial 3.13 leafing multiplepoppedstrandsinamagnetic-tapewind SEEpoppedstrand(3.19)andsteppedpack(3.29) 3.14 lifeexpectancy LE lengthoftimethatinformationispredictedtoberetrievableinasystem 3.15 loosepack undesirablepackconditioninarollofrecordingmaterial,suchthattheoute
42、rportionoftherollcanbemovedand tightenedbypullingontheend 3.16 magneticfieldintensity levelofthemagneticfieldatapointinspace 3.17 medium media,pl materialonwhichtheinformationisrecorded 3.18 medium-termstorageconditions storageconditionssuitableforthepreservationofrecordedinformationforaminimumof10y
43、ears 3.19 poppedstrand lateraldisplacementofasinglestrandorwrapofmagnetictapeextendingbeyondtheplaneofthetapepack SEEleafing(3.13)andsteppedpack(3.29) 3.20 print-through unwantedtransferofamagneticfieldanditssignalfromonetapelaptoanotherwithinarollofmagnetictapeISO18923:2000(E) 4 3.21 reel spool hub
44、orcorewithflanges(protectivesides)ontowhichrecordingmaterialiswound 3.22 relativehumidity RH ratio,definedasapercentage,oftheexistingpartialvapourpressureofwatertothevapourpressureatsaturation NOTE Itisusually,butnotalways,equaltothepercentageoftheamountofmoistureintheairtothatatsaturation. 3.23 she
45、ll cassette/cartridgehousingformagnetictape 3.24 slot spaceorslitinthehuborreelsurface 3.25 splice unionoftwopiecesofrecordingmaterialtoformasinglepiece 3.26 splicingtape paperorplasticstripcoatedwithathermal-orpressure-sensitiveadhesive,usedinsplicing 3.27 spoking deformationsinarollpackthatappearr
46、adiallyoutwardanddisruptthecircularnatureofthewind 3.28 staging processofconditioningmaterialfromonesetoftemperature/moistureconditionstoanother 3.29 steppedpack multipleadjacentstrandsofmagnetictapeextendingbeyondthelevelofatapepack SEEleafing(3.13)andpoppedstrand(3.19) 3.30 storageenvironment cond
47、itionsforstoringmaterials,i.e.,temperature,relativehumidity,cleanlinessoffacilities,andatmospheric pollutants 3.31 storagehousing physicalstructuresupportingmaterialsandtheirenclosures NOTE Itmayconsistofdrawers,racks,shelvesorcabinets. 3.32 system material,hardware,softwareanddocumentationnecessary
48、forrecordingand/orretrievinginformation 3.33 tapepack lengthofmagnetictapewoundonareelorhubISO18923:2000(E)5 3.34 tailsout configurationofmagnetictapestoredonitsreelorinitscassette,suchthatthetapeshouldbefullyrewoundin ordertocorrectlyplayfromthebeginningoftherecordedinformation 3.35 wind appearance
49、 physicalappearanceandtensionofthemagnetictapepack 3.36 wind process processoftransferringarollofrecordingmaterialfromonespoolorreeltoanother 4 Environmentalconditions 4.1 Humidityandtemperaturelimits 4.1.1 Medium-termstorageenvironment Theaveragerelativehumidityofamedium-termstorageenvironmentshallnotexceed50%RHandshallnotbe lowerthan15%RH.Themaximumtemperatureforprolongedperiodsshallnotexceed23C(seeTable1).The peaktemperatureforshorttimeperiodsshallnotexceed32C.Tapeshouldnotbestoredbelow8Cduetoa potentialproblemwithlubricantseparationfromthebinder. Cyclingof
