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Documenttype:InternationalStandardDocumentsubtype:Documentstage:(20)PreparatoryDocumentlanguage:EDocuments:MyDocuments:Work:ISO-TC154:WG5:N-Documents:ISO-TC154-WG5_N0038_ISO_WD_8601-1_2016-02-16.docxSTDVersion2.7f
ISO/TC154/WG5N0038Date:2016-02-16
ISO/WD8601-1
ISO/TC154/WG5
Secretariat:SAC
Dataelementsandinterchangeformats—Informationinterchange-Representationofdatesandtimes—Part1:BasicrulesElémentsdedonnéesetformatsd'échange—Échanged'information-Représentationdeladateetdel'heure—Partie1:Règlesdebase
Warning
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Contents Page
Foreword.......................................................................................................................................................................iv
Introduction..................................................................................................................................................................iv
1 Scope..................................................................................................................................................................1
2 Termsanddefinitions..................................................................................................................................12.1 Basicconcepts.................................................................................................................................................12.2 Timeunits,nominaldurationsandtimeintervals.............................................................................52.3 Representationsandformats....................................................................................................................7
3 Fundamentalprinciples..............................................................................................................................83.1 Basicrules........................................................................................................................................................83.2 Timescales.......................................................................................................................................................93.3 Representationsandformatrepresentations..................................................................................113.4 Charactersusedintherepresentations..............................................................................................123.5 Expansion......................................................................................................................................................143.6 Leadingzeros...............................................................................................................................................143.7 Mutualagreement......................................................................................................................................14
4 Dateandtimerepresentations..............................................................................................................144.1 Date..................................................................................................................................................................144.2 Timeofday....................................................................................................................................................174.3 Dateandtimeofday..................................................................................................................................204.4 Timeinterval................................................................................................................................................224.5 Recurringtimeinterval............................................................................................................................26
5 Dateandtimeformatrepresentations................................................................................................27
AnnexA(informative)RelationshiptoISO2014,ISO2015,ISO2711,ISO3307andISO4031.........................................................................................................................................................28
AnnexB(informative)Examplesofrepresentations..................................................................................29
Bibliography...............................................................................................................................................................35
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of nationalstandards bodies (ISO member bodies). The work of preparing International Standards is normallycarriedout through ISO technical committees.Eachmemberbody interested ina subject forwhichatechnical committee has been established has the right to be represented on that committee.Internationalorganizations,governmentalandnon-governmental,inliaisonwithISO,alsotakepartinthe work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on allmattersofelectrotechnicalstandardization.
The procedures used to develop this document and those intended for its further maintenance aredescribedintheISO/IECDirectives,Part1.InparticularthedifferentapprovalcriterianeededforthedifferenttypesofISOdocumentsshouldbenoted.ThisdocumentwasdraftedinaccordancewiththeeditorialrulesoftheISO/IECDirectives,Part2(seewww.iso.org/directives).
Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectofpatentrights. ISOshallnotbeheldresponsiblefor identifyinganyorallsuchpatentrights.DetailsofanypatentrightsidentifiedduringthedevelopmentofthedocumentwillbeintheIntroductionand/orontheISOlistofpatentdeclarationsreceived(seewww.iso.org/patents).
Anytradenameusedinthisdocumentisinformationgivenfortheconvenienceofusersanddoesnotconstituteanendorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformityassessment, as well as information about ISO's adherence to the WTO principles in the TechnicalBarrierstoTrade(TBT)seethefollowingURL:Foreword-Supplementaryinformation
The committee responsible for this document is ISO/154,Processes, data elements and documents incommerce,industryandadministration.
Thisfourtheditioncancelsandreplacesthethirdedition(ISO8601:2004),whichhasbeentechnicallyrevisedwiththefollowingchanges:
— ConversionofthecontentasPart1withtheparttitle"Basicrules"duetotheadditionofanotherPart2"Extensions"ofISO8601;
— Elimination of the term "midnight" and changes to the use of the value '24' for hour. This is inresponse to requests from the Information Technology user communities to (1) removeambiguities caused by the term "midnight", which has been replaced by "Beginning of day" and"Endofday"; and (2) align the representationof thebeginning/endofdaywith currentde factoindustrypractice;
— Amendment of the recurring time interval (2.1.17 and 4.5) to provide a link to Part 2 whichcontainsinsection5the‘RepeatRulesforRecurringTimeIntervals’.
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ISO8601consistsofthefollowingparts,underthegenerictitleDataelementsandinterchangeformats—Informationinterchange-Representationofdatesandtimes:
— Part1:Basicrules
— Part2:Extensions
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Introduction
Although ISORecommendations andStandards in this fieldhavebeen available since1971, differentformsofnumeric representationofdatesand timeshavebeen in commonuse indifferent countries.Where such representations are interchanged across national boundaries misinterpretation of thesignificanceofthenumeralscanoccur,resultinginconfusionandotherconsequentialerrorsorlosses.ThepurposeofthisInternationalStandardistoeliminatetheriskofmisinterpretationandtoavoidtheconfusionanditsconsequences.
This International Standard includes specifications for a numeric representation of informationregarding date and time of day. In addition this International Standard includes specifications forrepresentationoftheformatsofthesenumericrepresentations.
In order to achieve similar formats for the representations of calendar dates, ordinal dates, datesidentifiedbyweeknumber,timeintervals,recurringtimeintervals,combineddateandtimeofday,anddifferencesbetweenlocaltimeandUTCofday,andtoavoidambiguitiesbetweentheserepresentations,ithasbeennecessarytouse,apartfromnumericcharacters,eithersinglealphabeticcharactersorothergraphiccharactersoracombinationofalphabeticandothercharactersinsomeoftherepresentations.
TheaboveactionhashadthebenefitofenhancingtheversatilityandgeneralapplicabilityofpreviousInternational Standards in this field, and provides for the unique representation of any date or timeexpressionorcombinationof these.Eachrepresentationcanbeeasily recognized,which isbeneficialwhenhumaninterpretationisrequired.
ThisInternationalStandardretainsthemostcommonlyusedexpressionsfordateandtimeofdayandtheirrepresentationsfromtheearlierInternationalStandardsandprovidesuniquerepresentationsforsomenewexpressionsusedinpractice.Itsapplicationininformationinterchange,especiallybetweendataprocessingsystemsandassociatedequipmentwilleliminateerrorsarisingfrommisinterpretationand the costs these generate. The promotion of this International Standard will not only facilitateinterchangeacrossinternationalboundaries,butwillalsoimprovetheportabilityofsoftware,andwilleaseproblemsofcommunicationwithinanorganization,aswellasbetweenorganizations.
Several of the alphabetic and graphic characters used in the text of this International Standard arecommonbothtotherepresentationsspecifiedandtonormaltypographicalpresentation.NotethatforunitsoftimeinplaintextthesymbolsgiveninISO31-1shouldbeused.
To avoid confusion between the representations and the actual text, its punctuation marks andassociatedgraphiccharacters,alltherepresentationsarecontainedinbrackets[].Thebracketsarenotpartof therepresentation,andshouldbeomittedwhen implementingtherepresentations.Allmatteroutsidethebracketsisnormaltext,andnotpartoftherepresentation.Intheassociatedexamples,thebracketsandtypographicalmarkingsareomitted.
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Dataelementsandinterchangeformats—Informationinterchange-Representationofdatesandtimes—Part1:Basicrules
1 Scope
ThisInternationalStandardisapplicablewheneverrepresentationofdates intheGregoriancalendar,timesinthe24-hourtimekeepingsystem,timeintervalsandrecurringtimeintervalsoroftheformatsoftheserepresentationsareincludedininformationinterchange.Itincludes
— calendardatesexpressedintermsofcalendaryear,calendarmonthandcalendardayofthemonth;
— ordinaldatesexpressedintermsofcalendaryearandcalendardayoftheyear;
— weekdates expressed in termsof calendar year, calendarweeknumber and calendarday of theweek;
— localtimebaseduponthe24-hourtimekeepingsystem;
— CoordinatedUniversalTimeofday;
— localtimeandthedifferencefromCoordinatedUniversalTime;
— combinationofdateandtimeofday;
— timeintervals;
— recurringtimeintervals.
ThisInternationalStandarddoesnotcoverdatesandtimeswherewordsareusedintherepresentationanddatesandtimeswherecharactersarenotusedintherepresentation.
ThisInternationalStandarddoesnotassignanyparticularmeaningorinterpretationtoanydataelementthat uses representations in accordance with this International Standard. Such meaning will bedeterminedbythecontextoftheapplication.
2 Termsanddefinitions
Forthepurposesofthisdocument,thefollowingtermsanddefinitionsapply.
2.1 Basicconcepts
2.1.1timeaxismathematicalrepresentationofthesuccessionintimeofinstantaneouseventsalongauniqueaxis
[IEC60050-111]
2.1.2instantpointonthetimeaxis
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[IEC60050-111]
Notetoentry: Aninstantaneouseventoccursataspecificinstant.
2.1.3timeintervalpartofthetimeaxislimitedbytwoinstants
[IEC60050-111]
Notetoentry: Atimeintervalcomprisesallinstantsbetweenthetwolimitinginstantsand,unlessotherwisestated,thelimitinginstantsthemselves.
2.1.4timescalesystemoforderedmarkswhichcanbeattributedtoinstantsonthetimeaxis,oneinstantbeingchosenastheorigin
[IEC60050-111]
Note1toentry: Atimescalemayamongstothersbechosenas:— continuous,e.g.internationalatomictime(TAI)(seeIEC60050-713,item713-05-18);— continuouswith discontinuities, e.g. CoordinatedUniversal Time (UTC) due to leap seconds, standard time
duetosummertimeandwintertime;— successive steps, e.g. usual calendars,where the time axis is split up into a succession of consecutive time
intervalsandthesamemarkisattributedtoallinstantsofeachtimeinterval;— discrete,e.g.indigitaltechniques.
Note2toentry: Forphysicalandtechnicalapplications,atimescalewithquantitativemarksispreferred,basedonachoseninitialinstanttogetherwithaunitofmeasurement.
Note3toentry: Customary time scales use various units of measurement in combination, such as second,minute,hour,orvarioustimeintervalsofthecalendarsuchascalendarday,calendarmonthandcalendaryear.
Note4toentry: Atimescalehasareferencepointwhichattributesoneofthemarksofthetimescaletooneoftheinstants,thusdeterminingtheattributionofmarkstoinstantsforthetimescale.
2.1.5timepointdatetimemarkattributedtoaninstantbymeansofaspecifiedtimescale
[IEC60050-111]
Note1toentry: Ona timescale consistingof successive steps, twodistinct instantsmaybeexpressedby thesametimepoint(seeNote1oftheterm“timescale”).
Note2toentry: For many time scales with quantitative marks, the numerical value of the time point of aninstantmayalsobeconsideredtobeequaltothedurationbetweentheoriginofthetimescaleandtheconsideredinstant.
Note3toentry: InIEC60050-111thisdefinitioncorrespondswiththeterm“date”.
Note4toentry: The term “time” is often used in common language. However, it should only be used if themeaningisclearlyvisiblefromthecontext,sincetheterm“time”isalsousedwithothermeanings.
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2.1.6durationnon-negativequantityattributedtoatimeinterval,thevalueofwhichisequaltothedifferencebetweenthetimepointsofthefinalinstantandtheinitialinstantofthetimeinterval,whenthetimepointsarequantitativemarks
[IEC60050-111]
Note1toentry: Inthecaseofdiscontinuitiesinthetimescale,suchasaleapsecondorthechangefromwintertimetosummertimeandback,thecomputationofthedurationrequiresthesubtractionoradditionofthechangeofdurationofthediscontinuity.
Note2toentry: DurationisoneofthebasequantitiesintheInternationalSystemofQuantities(ISQ)onwhichtheInternationalSystemofUnits(SI)isbased.Theterm“time”insteadof“duration”isoftenusedinthiscontext.
Note3toentry: Fortheterm“duration”,expressionssuchas“time”or“timeinterval”areoftenused.Theterm“time” is not recommended in this sense and the term “time interval” is deprecated in this sense to avoidconfusionwiththeconcept“timeinterval”.
Note4toentry: TheSIunitofdurationisthesecond.
2.1.7nominaldurationdurationexpressedamongstothersinyears,months,weeksordays
Notetoentry: Thedurationofacalendaryear,acalendarmonth,acalendarweekoracalendardaydependson itsposition in thecalendar.Therefore, theexactdurationofanominaldurationcanonlybeevaluated if thedurationofthecalendaryears,calendarmonths,calendarweeksorcalendardaysusedareknown.
2.1.8datetime point representing a calendar day on a time scale consisting of an origin and a succession ofcalendardays
Notetoentry: InIEC60050-111thisdefinitioncorrespondswiththeterm“calendardate”.
2.1.9calendardatedate representing a particular calendar day by its calendar year, its calendarmonth and its ordinalnumberwithinitscalendarmonth
2.1.10ordinaldatedate representing a particular calendar day by its calendar year and its ordinal number within itscalendaryear
2.1.11weekdatedaterepresentingaparticularcalendardaybythecalendaryeartowhichitscalendarweekbelongs,theordinal number of its calendar week within that calendar year and its ordinal number within itscalendarweek
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2.1.12CoordinatedUniversalTimeUTCtimescalewhichformsthebasisofacoordinatedradiodisseminationofstandardfrequenciesandtimesignals;itcorrespondsexactlyinratewithinternationalatomictime,butdiffersfromitbyanintegralnumberofseconds
[IEC60050-713]
Note1toentry: UTC is established by the International Bureau ofWeights andMeasures (BIPM, i.e. BureauInternationaldesPoidsetMesures)andtheInternationalEarthRotationService(IERS).UTCprovidesthebasisofstandard time, the use ofwhich is legal inmost countries. The 15th Conférence Géneral des Poids etMesures(CGPM)(1975)judgedinitsResolution5thatthisusagecanbestronglyrecommended.
Note2toentry: UTCisadjustedtoUT1bytheinsertionordeletionofseconds,knownas“leapseconds”.
Note3toentry: Greenwich Mean Time (GMT) is internationally replaced by UTC. UTC is often (incorrectly)referredtoasGMT.UTCisgenerallyusedbyaviationandmaritimenavigationthatalsouseslocalapparenttimeandlocalmeantimeforcelestialnavigation(seeISO19018).
Note4toentry: Additionalinformationcanbefoundasfollows:— theURLfortheITUhttp://www.itu.int/itudoc/itu-r/rec/tf/index.html— theURLfortheInternationalBureauofWeightsandMeasureshttp://www.bipm.fr— theURLfortheInternationalEarthRotationServicehttp://hpiers.obspm.fr.
2.1.13UTCofdayquantitativeexpressionmarkinganinstantwithinacalendardayinaccordancewithUTC
2.1.14standardtimetimescalederivedfromcoordinateduniversaltime,UTC,byatimeshiftestablishedinagivenlocationbythecompetentauthority
[IEC60050-111]
Notetoentry: Thistimeshiftmaybevariedinthecourseofayear.
2.1.15standardtimeofdayquantitative expression marking an instant within a calendar day by the duration elapsed after thebeginningofthedayinthelocalstandardtime
[IEC60050-111]-->duetothechangeddefinitionthereferenceneedstobedeleted!
Notetoentry: Standardtimeofdayiscalled“clocktime”inIEC60050-111.
2.1.16localtimelocallyapplicabletimeofdaysuchasstandardtimeofday,oranon-UTCbasedtimeofday
2.1.17recurringtimeintervalseriesofconsecutivetimeintervalsofthesamedurationornominalduration
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Note1toentry: Ifthedurationofthetimeintervalsismeasuredincalendarentities,thedurationofeachtimeintervaldependsonthecalendardatesofitsstartanditsend.
Note2toentry: If the time interval is repeating toasetof rules, section5– “RepeatRules forRecurringTimeIntervals”,ofISO8601Parttoshallbeapplied.
2.2 Timeunits,nominaldurationsandtimeintervals
2.2.1secondbase unit of measurement of time in the International System of Units (SI) as defined by theInternational Committee of Weights and Measures (CIPM, i.e. Comité International des Poids etMesures)
Note1toentry: SeealsoISO31-1.
Note2toentry: Itisthebaseunitforexpressingduration.
2.2.2leapsecondintentional timestepofone second toadjustUTC toensureappropriateagreementwithUT1, a timescalebasedontherotationoftheEarth
[Rec.ITU-RTF.460-5]
NOTE Aninsertedsecondiscalledpositiveleapsecondandanomittedsecondiscallednegativeleapsecond.Apositive leapsecondis insertedbetween[23:59:59Z]and[24:00:00Z]andcanberepresentedas[23:59:60Z].Negative leap seconds are achieved by the omission of [23:59:59Z]. Insertion or omission takes place asdeterminedbyIERS,normallyon30Juneor31December,butifnecessaryon31Marchor30September.
2.2.3minuteunitoftime,equalto60seconds
[ISO31-1]
2.2.4hourunitoftime,equalto60minutes
[ISO31-1]
2.2.5day〈unitoftime〉unitoftime,equalto24hours
[ISO31-1]
2.2.6calendardaytime interval starting at thebeginningof theday and endingwith thebeginningof thenext day, thelatterbeingthestartinginstantofthenextcalendarday
Note1toentry: Acalendardayisoftenalsoreferredtoasday.
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Note2toentry: Thedurationofacalendardayis24hours;exceptifmodifiedby:— theinsertionordeletionofleapseconds,bydecisionoftheInternationalEarthRotationService(IERS),or— theinsertionordeletionofothertimeintervals,asmaybeprescribedbylocalauthoritiestoalterthetime
scaleoflocaltime.
2.2.7day〈duration〉durationofacalendarday
Notetoentry: Theterm“day”appliesalsotothedurationofanytimeintervalwhichstartsatacertaintimeofdayatacertaincalendardayandendsatthesametimeofdayatthenextcalendarday.
2.2.8calendarweektimeintervalofsevencalendardaysstartingwithaMonday
Note1toentry: Acalendarweekisoftenalsoreferredtoasweek.
Note2toentry: See3.2.2forthenamesofthecalendardaysandtheirdaynumbers.
Note3toentry: Acalendarweekmaybeidentifiedbyitsordinalnumberwithinitscalendaryear.
2.2.9weekdurationofacalendarweek
Notetoentry: Theterm“week”appliesalsotothedurationofanytimeintervalwhichstartsatacertaintimeofdayatacertaincalendardayandendsatthesametimeofdayatthesamecalendardayofthenextcalendarweek.
2.2.10calendarweeknumberordinalnumberwhichidentifiesacalendarweekwithinitscalendaryearaccordingtotherulethatthefirstcalendarweekofayearisthatonewhichincludesthefirstThursdayofthatyearandthatthelastcalendarweekofacalendaryearistheweekimmediatelyprecedingthefirstcalendarweekofthenextcalendaryear
2.2.11calendarmonthtime interval resulting from the division of a calendar year in 12time intervals, eachwith a specificnameandcontainingaspecificnumberofcalendardays
Note1toentry: Acalendarmonthisoftenreferredtoasmonth.
Note2toentry: See3.2.1forthenamesofthemonthsofthecalendaryearintheGregoriancalendar,listedintheir order of occurrence, for their number of days, and for the ordinal dates of the days in common and leapyears.
2.2.12monthdurationof28,29,30or31calendardaysdependingonthestartand/ortheendofthecorrespondingtimeintervalwithinthespecificcalendarmonth
Note1toentry: Theterm“month”appliesalsotothedurationofanytimeintervalwhichstartsatacertaintimeofdayatacertaincalendardayofthecalendarmonthandendsatthesametimeofdayatthesamecalendardayofthenextcalendarmonth,ifitexists.Inothercasestheendingcalendardayhastobeagreedon.
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Note2toentry: Incertainapplicationsamonthisconsideredasadurationof30calendardays.
2.2.13calendaryearcyclictimeintervalinacalendarwhichisrequiredforonerevolutionoftheEartharoundtheSunandapproximatedtoanintegralnumberofcalendardays
Note1toentry: Acalendaryearisoftenalsoreferredtoasyear.
Note2toentry: UnlessotherwisespecifiedthetermdesignatesinthisInternationalStandardacalendaryearintheGregoriancalendar.
2.2.14yeardurationof365or366calendardaysdependingonthestartand/ortheendofthecorrespondingtimeintervalwithinthespecificcalendaryear
Notetoentry: Theterm“year”appliesalsotothedurationofanytimeintervalwhichstartsatacertaintimeofdayatacertaincalendardateofthecalendaryearandendsatthesametimeofdayatthesamecalendardateofthenextcalendaryear,ifitexists.Inothercasestheendingcalendardatehastobeagreedon.
2.2.15Gregoriancalendarcalendar ingeneraluse, introducedin1582todefineacalendaryearthatmorecloselyapproximatedthetropicalyearthantheJuliancalendar
Notetoentry: In this International Standard the termGregorian calendar is used to refer to the time scaledescribedin3.2.1.
2.2.16commonyearcalendaryearintheGregoriancalendarthathas365calendardays
2.2.17leapyearcalendaryearintheGregoriancalendarthathas366calendardays
2.2.18centennialyearcalendaryearintheGregoriancalendarwhoseyearnumberisdivisiblewithoutremainderbyhundred
2.3 Representationsandformats
2.3.1dateandtimerepresentationexpressionindicatingatimepoint,timeintervalorrecurringtimeinterval
2.3.2dateandtimeformatrepresentationexpressiondescribingtheformatofagroupofdateandtimerepresentations
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2.3.3basicformatformat of a date and time representation or date and time format representation comprising theminimumnumberoftimeelementsnecessaryfortheaccuracyrequired
Notetoentry: Thebasicformatshouldbeavoidedinplaintext.
2.3.4extendedformatextensionofthebasicformatthatincludesadditionalseparators
2.3.5completerepresentationrepresentationthatincludesallthedateandtimecomponentsassociatedwiththeexpression;limited,ifapplicable,fortimeelementsofrepresentationsexpressingacalendaryeartofourdigits
2.3.6decimalrepresentationexpansionofarepresentationbyadditionofadecimal fractiontothe lowestordercomponentof theexpression
2.3.7representationwithreducedaccuracyabbreviationofarepresentationbyomissionoflowerordercomponents
2.3.8expandedrepresentationexpansionofarepresentationtoallowidentificationofdatesincalendaryearsoutsidetherange[0000]till[9999]
3 Fundamentalprinciples
3.1 Basicrules
ThisInternationalStandardgivesasetofrulesfortherepresentationof
— timepoints,
— timeintervals,
— recurringtimeintervals.
Bothaccurateandapproximaterepresentationscanbeidentifiedbymeansofuniqueandunambiguousexpressionsspecifyingtherelevantdates,timesofdayanddurations.Thedegreeofaccuracyrequiredandobtainablecanbevariedbyincludingordeletingtheappropriatetimeelements(suchasseconds).
Inaddition,thisInternationalStandardgivesrulesfortherepresentationofexpressionsdescribingtheformatoftheaboverepresentations.
Thedecreasingorderoftimeelements,left-to-right,iscommontotheserepresentations.
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3.2 Timescales
3.2.1 TheGregoriancalendar
This International Standard uses the Gregorian calendar for the identification of calendar days. Thiscalendarprovidesatimescaleconsistingofa,potentially infinite,seriesofcontiguouscalendaryears.Consecutivecalendaryearsareidentifiedbysequentiallyassignedyearnumbers.
TheGregoriancalendardistinguishescommonyearsof365consecutivecalendardaysandleapyearsof366consecutivecalendardays.Aleapyearisayearwhoseyearnumberisdivisiblebyfouranintegralnumberof times.However,acentennialyear isnota leapyearunless itsyearnumber isdivisiblebyfourhundredanintegralnumberoftimes.
In the Gregorian calendar each calendar year is divided in 12sequential calendar months, eachconsistingofaspecificnumberofcalendardaysasindicatedinTable1.
The Gregorian calendar has a reference point that assigns 20May1875 to the calendar day that the“ConventionduMètre”wassignedinParis.
ThisInternationalStandardallowstheidentificationofcalendaryearsbytheiryearnumberforyearsboth before and after the introduction of the Gregorian calendar. For the determination of calendaryears,theyearnumberandthecalendardaywithinthecalendaryearonlytherulesmentionedaboveareused.ForthepurposesofthisInternationalStandardthecalendarbasedontheserulesisreferredto as the Gregorian calendar. The use of this calendar for dates preceding the introduction of theGregoriancalendar(alsocalled theprolepticGregoriancalendar)shouldonlybebyagreementof thepartnersininformationinterchange.
TheintroductionoftheGregoriancalendarincludedthecancellationoftheaccumulatedinaccuraciesofthe Julian calendar. However, no dates shall be inserted or deleted when determining dates in theprolepticGregoriancalendar.
NOTE IntheprolepticGregoriancalendar,thecalendaryear[0000]isaleapyear.
EXAMPLE TheGregoriancalendarwasintroducedon15October1582.Inthecalendarsetbythisstandardthe calendar day preceding that calendar day is referred to as 14October1582. In the Julian calendar thatcalendardayisreferredtoas4October1582.
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Table1—Calendarmonths
Calendarmonthnumber
Calendarmonthname
Numberofdaysinthemonth
Ordinaldatesofthedaysincommonyears
Ordinaldatesofthedaysinleapyears
01 January 31 001-031 001-031
02 February 28(leapyear29) 032-059 032-060
03 March 31 060-090 061-091
04 April 30 091-120 092-121
05 May 31 121-151 122-152
06 June 30 152-181 153-182
07 July 31 182-212 183-213
08 August 31 213-243 214-244
09 September 30 244-273 245-274
10 October 31 274-304 275-305
11 November 30 305-334 306-335
12 December 31 335-365 336-366
3.2.2 Theweekcalendar
This International Standard allows the use of the week calendar time scale for the identification ofcalendardays.
This time scale is based on an unbounded series of contiguous calendar weeks. The calendar weeknumberidentifiesthecalendarweekwithinthecalendaryear.EachcalendarweekhassevencalendardaysasindicatedinTable2.
ThereferencepointofthetimescaleassignsSaturdayto1January2000.
Table2—Calendardays
Ordinaldaynumberintheweek Calendardayname
1 Monday
2 Tuesday
3 Wednesday
4 Thursday
5 Friday
6 Saturday
7 Sunday
NOTE1 Acalendaryearhas52or53calendarweeks.
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NOTE2 Thefirstcalendarweekofacalendaryearincludesuptothreedaysfromthepreviouscalendaryear;thelastcalendarweekofacalendaryearincludesuptothreedaysfromthefollowingcalendaryear.Therefore,forcertaincalendardaysthecalendardatecontainsadifferentcalendaryearthantheweekdate.Forinstance:— Sunday1January1995isidentifiedbythecalendardate[1995-01-01]andweekdate[1994-W52-7]— Tuesday31December1996isidentifiedbythecalendardate[1996-31-12]andweekdate[1997-W01-2].
NOTE3 The rule for determining the first calendar week (see the definition of calendar week number inClause2)isequivalentwiththerule“thefirstcalendarweekisthecalendarweekwhichincludes4January”.
3.2.3 Timescaleswithinthecalendarday
This International Standard recommends the use of time scales applying the 24-hour time keepingsystemfortheidentificationoftimepointswithinacalendarday.
Thesetimescalesprovidemarkswhich,exceptincaseofdiscontinuities,representthedurationelapsedafter the start of the calendar day. In this International Standard thesemarks,which are collectivelyreferredtoastimeofday,arerepresentedbythenumberofhourselapsedafter thebeginningof theday,thenumberofminuteselapsedafterthelastfullhour,thenumberofsecondselapsedafterthelastfullminute,withdecimalpartsofasecondifnecessary.
3.3 Representationsandformatrepresentations
ThisInternationalStandarddefinesdateandtimerepresentationstoexpresstimepoints,timeintervalsandrecurringtimeintervals.
EXAMPLE Thedateandtimerepresentation[2003-02-10]identifies10February2003.
Todefine thedateand timerepresentationspermittedby this InternationalStandard,use ismadeofdateandtimeformatrepresentationsinwhichspecificcharactersareusedtorepresentdigitsorothercharacters indateandtimerepresentations.Adateandtime formatrepresentation, togetherwith itsdescription,definespermitteddateandtimerepresentations.
EXAMPLE The date and time format representation [YYYY-MM-DD], together with the associateddescription,definesthecomplete,extendedformat,calendardaterepresentationspermittedbythisInternationalStandard.
Bymutual agreement the parties in information interchangemay transfer the date and time formatrepresentations. Only the date and time format representations permitted by this InternationalStandardshallbeused.
Thedateand time format representationsuse characters thatpotentiallyexpand intomore thanonecharacter in the date and time representation; this is indicated by underlining. If at the time ofinformation interchange of the date and time format representation the number of characters to beused in the date and time representation is known, the variable expansion representation (i.e.underlining)shallnotbeused.
EXAMPLE Local timewith threedecimals for the fractionof theseconds is representedby [hh:mm:ss,sss],notby[hh:mm:ss,s].
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3.4 Charactersusedintherepresentations
3.4.1 Introduction
TherepresentationsspecifiedinthisInternationalStandardmakeuseofgraphiccharactersasspecifiedin 3.4. Note that, except for “hyphen”, “minus” and “plus-minus”, these characters are part of theISO/IEC646repertoire.
In an environmentwhereuse ismadeof a character repertoirebasedon ISO/IEC646, “hyphen” and“minus”arebothmappedonto“hyphen-minus”.Representationswitha“plus-minus”shallonlybeusedinsuchenvironmentiftheinterchangerepertoireincludes“plus-minus”.
In an environment where use is made of the ITU-TS.1 repertoire (e.g. telex) date and time formatrepresentationsshallnotbeused.
Indateandtimeformatrepresentationsunderliningofcharactersisused.Inenvironmentsthatdonotsupport the representation of underlined characters, the underline shall precede the character to beunderlined.
NOTE1 Indateandtimerepresentationslowercasecharactersmaybeusedwhenuppercasecharactersarenotavailable.
NOTE2 EncodingofcharactersfortheinterchangeofdatesandtimesisnotinthescopeofthisInternationalStandard.
Unlessexplicitlyallowedbythis InternationalStandardthecharacter“space”shallnotbeused in therepresentations.
3.4.2 Charactersusedinplaceofdigitsorsigns
In date and time format representations characters are used to represent characters in thedate andtimerepresentationsasfollows:
[Y] representsadigitusedinthetimeelement“year”;
[M]representsadigitusedinthetimeelement“month”;
[D] representsadigitusedinthetimeelement“day”;
[w] representsadigitusedinthetimeelement“week”;
[h] representsadigitusedinthetimeelement“hour”;
[m]representsadigitusedinthetimeelement“minute”;
[s] representsadigitusedinthetimeelement“second”;
[n] representsadigitfromapositiveintegerorzero;
[±] representsaplussign[+]ifincombinationwiththefollowingelementapositivevalueorzeroneedstoberepresented(inthiscase,unlessexplicitlystatedotherwise,theplussignshallnotbeomitted),oraminussign[−]ifincombinationwiththefollowingelementanegativevalueneedstoberepresented.
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Inadditionthefollowingconventionapplies:
[_] Whenanyofthecharactersrepresentingadigitisunderlined,itrepresentszeroormoredigitsinthecorrespondingdateandtimerepresentation.
Other characters in the date and time format representations are copied in the date and timerepresentations.
3.4.3 Charactersusedasdesignators
Inrepresentationsthefollowingcharactersareusedasdesignators:
[P] isusedasdurationdesignator,precedingthecomponentwhichrepresentstheduration;
NOTE TheuseofthecharacterPisbasedonthehistoricaluseoftheterm“period”forduration.
[R] isusedasrecurringtimeintervaldesignator;
[T] isusedastimedesignatortoindicate:
— thestartoftherepresentationoflocaltimetodesignatelocaltimeexpressionsassuch,
— thestartoftherepresentationofthetimeofdayindateandtimeofdayexpressions,
— the startof the representationof thenumberofhours,minutesor seconds inexpressionsofduration;
[W]isusedasweekdesignator,precedingadataelementwhichrepresentstheordinalnumberofacalendarweekwithinthecalendaryear;
[Z] isusedasUTCdesignator.
Inrepresentationsofduration(4.4.3.2),thefollowingdesignatorsareusedaspartoftheexpression:
[Y][M][W][D][H][M][S]
NOTE1 Intheseexpressions,[M]maybeusedtoindicate“month”or“minute”,orboth.
NOTE2 In date and time format representations the interpretation of the characters [Y], [M] and [D] ascharactersusedinplaceofdigitsorasdesignatorsdependsontheirpositionintheexpression.
NOTE3 These designators are used for the designation of units of time and nominal durations in therepresentationsdefinedinthisInternationalStandard.ForthedesignationofunitsoftimeanddurationsinothercontextsISO31-1shouldbeapplied.
3.4.4 Charactersusedasseparators
Inrepresentationsthefollowingcharactersareusedasseparators:
[-](hyphen): toseparatethetimeelements“year”and“month”, “year”and“week”, “year”and“day”,“month”and“day”,and“week”and“day”;
[:](colon): toseparatethetimeelements“hour”and“minute”,and“minute”and“second”;
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[/](solidus): toseparatecomponentsintherepresentationoftimeintervalsandrecurringtimeintervals.
NOTE RepresentationsdefinedinthisInternationalStandardalsomakeuseofthedecimalseparator.
3.5 Expansion
By mutual agreement of the partners in information interchange, it is permitted to expand thecomponent identifying the calendar year, which is otherwise limited to four digits. This enablesreference to dates and times in calendar years outside the range supported by completerepresentations,i.e.beforethestartoftheyear[0000]oraftertheendoftheyear[9999].
3.6 Leadingzeros
Ifatimeelementinadefinedrepresentationhasadefinedlength,thenleadingzerosshallbeusedasrequired.
3.7 Mutualagreement
Some of the representations identified in this International Standard are only allowed by mutualagreement of the partners in information interchange. Such agreement should ensure that fields inwhich the representation may occur are not allowed to hold other representations that cannot beunambiguouslydistinguishedfromtheagreedrepresentation.
4 Dateandtimerepresentations
4.1 Date
4.1.1 General
For ease of comparison, in all the following examples of representations of dates, the date of12April1985isusedasanillustration,ifapplicable.
4.1.2 Calendardate
4.1.2.1 General
Inexpressionsofcalendardates
— calendar year is, unless specified otherwise, represented by four digits. Calendar years arenumberedinascendingorderaccordingtotheGregoriancalendarbyvaluesintherange[0000]to[9999].Valuesintherange[0000]through[1582]shallonlybeusedbymutualagreementofthepartnersininformationinterchange.
— calendar month is represented by two digits. January is represented by [01], and subsequentcalendarmonthsarenumberedinascendingsequence.
— calendardayof themonth is representedby twodigits. The first calendardayof any calendarmonth is represented by [01] and subsequent calendar days of the same calendar month arenumberedinascendingsequence.
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4.1.2.2 Completerepresentations
Whentheapplicationidentifiestheneedforacompleterepresentationofacalendardate,itshallbeoneof the numeric expressions as follows, where [YYYY] represents a calendar year, [MM] the ordinalnumberofacalendarmonthwithinthecalendaryear,and[DD]theordinalnumberofacalendardaywithinthecalendarmonth.
Basicformat: YYYYMMDD Example: 19850412Extendedformat: YYYY-MM-DD Example: 1985-04-12
4.1.2.3 Representationswithreducedaccuracy
If in a givenapplication it is sufficient to express a calendardatewith less accuracy thana completerepresentationasspecifiedin4.1.2.2,eithertwo,fourorsixdigitsmaybeomitted,theomissionstartingfromtheextremeright-handside.Theresultingrepresentationwillthenindicateamonth,ayearoracentury,assetoutbelow.Whenonly[DD]isomitted,aseparatorshallbeinsertedbetween[YYYY]and[MM],butseparatorsshallnotbeusedintheotherrepresentationswithreducedaccuracy.
a) AspecificmonthBasicformat: YYYY-MM Example: 1985-04Extendedformat: notapplicable
b) AspecificyearBasicformat: YYYY Example: 1985Extendedformat: notapplicable
c) AspecificcenturyBasicformat: YY Example: 19Extendedformat: notapplicable
4.1.2.4 Expandedrepresentations
If, by agreement, expanded representations are used, the formats shall be as specified below. Theinterchangepartiesshallagreetheadditionalnumberofdigitsinthetimeelementyear.Intheexamplesbelowithasbeenagreedtoexpandthetimeelementyearwithtwodigits.
a) AspecificdayBasicformat: ±YYYYYMMDD Example: +0019850412Extendedformat: ±YYYYY-MM-DD Example: +001985-04-12
b) AspecificmonthBasicformat: ±YYYYY-MM Example: +001985-04Extendedformat: notapplicable
c) AspecificyearBasicformat: ±YYYYY Example: +001985Extendedformat: notapplicable
d) AspecificcenturyBasicformat: ±YYY Example: +0019Extendedformat: notapplicable
NOTE 4.1.2.4includesthedefinitionofrepresentationsthatareexpandedandhavereducedaccuracy.
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4.1.3 Ordinaldate
4.1.3.1 General
Inexpressionsofordinaldates
— calendaryearisrepresentedasin4.1.2.
— calendar day of the year is represented by three decimal digits. The first calendar day of anycalendaryear is representedby [001] and subsequent calendardays arenumbered in ascendingsequence.
4.1.3.2 Completerepresentations
Whentheapplicationidentifiestheneedforacompleterepresentationofanordinaldate,itshallbeoneofthenumericexpressionsasfollows,where[YYYY]representsacalendaryearand[DDD]theordinalnumberofacalendardaywithinthecalendaryear.
Basicformat: YYYYDDD Example: 1985102Extendedformat: YYYY-DDD Example: 1985-102
4.1.3.3 Expandedrepresentations
If, by agreement, expanded representations are used the formats shall be as specified below. Theinterchangepartiesshallagreetheadditionalnumberofdigitsinthetimeelementyear.Intheexamplesbelowithasbeenagreedtoexpandthetimeelementyearwithtwodigits.
AspecificdayBasicformat: ±YYYYYDDD Example: +001985102Extendedformat: ±YYYYY-DDD Example: +001985-102
4.1.4 Weekdate
4.1.4.1 General
Inexpressionsofweekdates
— calendaryearisrepresentedasin4.1.2.
— calendarweek is represented by two decimal digits. The first calendarweek of a year shall beidentifiedas[01]andsubsequentweeksshallbenumberedinascendingsequence.
— calendar day of the week is represented by one decimal digit. Monday shall be identified ascalendarday [1]ofanycalendarweek,andsubsequentcalendardaysof thesamecalendarweekshallbenumberedinascendingsequencetoSunday(calendarday[7]).
4.1.4.2 Completerepresentations
Whentheapplicationidentifiestheneedforacompleterepresentationofaweekdate,itshallbeoneofthe alphanumeric expressions as follows,where [YYYY] represents a calendar year, [W] is theweekdesignator,[ww]representstheordinalnumberofacalendarweekwithintheyear,and[D]representstheordinalnumberofacalendardaywithinthecalendarweek.
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Basicformat: YYYYWwwD Example: 1985W155Extendedformat: YYYY-Www-D Example: 1985-W15-5
4.1.4.3 Representationswithreducedaccuracy
Ifthedegreeofaccuracyrequiredpermits,onedigitmaybeomittedfromtherepresentationin4.1.4.2.
AspecificweekBasicformat: YYYYWww Example: 1985W15Extendedformat: YYYY-Www Example: 1985-W15
4.1.4.4 Expandedrepresentations
If, by agreement, expanded representations are used the formats shall be as specified below. Theinterchangepartiesshallagreetheadditionalnumberofdigitsinthetimeelementyear.Intheexamplesbelowithasbeenagreedtoexpandthetimeelementyearwithtwodigits.
a) AspecificdayBasicformat: ±YYYYYWwwD Example: +001985W155Extendedformat: ±YYYYY-Www-D Example: +001985-W15-5
b) AspecificweekBasicformat: ±YYYYYWww Example: +001985W15Extendedformat: ±YYYYY-Www Example: +001985-W15
NOTE 4.1.4.4includesthedefinitionofrepresentationsthatareexpandedandhavereducedaccuracy.
4.2 Timeofday
4.2.1 General
ThisInternationalStandardisbasedonthe24-hourtimekeepingsystemthatisnowincommonuse.Inexpressionsoftimeofday
— hour is represented by two digits from [00] to [24]. The representation of the hour by [24] isallowedonlytoindicatetheendofacalendardaywithinatimeinterval,see4.2.3.
— minuteisrepresentedbytwodigitsfrom[00]to[59].
— secondisrepresentedbytwodigitsfrom[00]to[60].Therepresentationofthesecondby[60]isallowedonlytoindicateapositiveleapsecondoraninstantwithinthatsecond.
NOTE TheseexpressionsapplytobothUTCandnon-UTCbasedtimescalesfortimeofday.
4.2.2 Localtime
4.2.2.1 General
In the representations of local time as defined below no provisions have been made to preventambiguitiesinexpressionsthatresultfromdiscontinuitiesinthetimescaleof localtime(e.g.daylightsavingtime).Whenanapplicationidentifiestheneedtopreventtheseambiguities,usecanbemadeoftheprovisionof4.2.5.2.
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4.2.2.2 Completerepresentations
When the application identifies the need for an expression of local time then the complete re-presentationshallbeasinglenumericexpressioncomprisingsixdigitsinthebasicformat,where[hh]representshours,[mm]minutesand[ss]seconds.
Basicformat: hhmmss Example: 232050Extendedformat: hh:mm:ss Example: 23:20:50
4.2.2.3 Representationswithreducedaccuracy
Ifthedegreeofaccuracyrequiredpermits,eithertwoorfourdigitsmaybeomittedfromtherepresen-tationin4.2.2.2.
a) AspecifichourandminuteBasicformat: hhmm Example: 2320Extendedformat: hh:mm Example: 23:20
b) AspecifichourBasicformat: hh Example: 23Extendedformat: notapplicable
4.2.2.4 Representationswithdecimalfraction
Ifnecessaryforaparticularapplicationadecimalfractionofhour,minuteorsecondmaybeincluded.Ifa decimal fraction is included, lower order time elements (if any) shall be omitted and the decimalfractionshallbedividedfromtheintegerpartbythedecimalsignspecifiedinISO31-0,i.e.thecomma[,]orfullstop[.].Ofthese,thecommaisthepreferredsign.Ifthemagnitudeofthenumberislessthanunity,thedecimalsignshallbeprecededbytwozerosinaccordancewith3.6.
Theinterchangeparties,dependentupontheapplication,shallagreethenumberofdigitsinthedecimalfraction.Theformatshallbe[hhmmss,ss],[hhmm,mm]or[hh,hh]asappropriate(hourminutesecond,hourminute, and hour, respectively),with asmany digits as necessary following the decimal sign. Adecimal fraction shall have at least one digit. In the examples below it has been agreed to give thesmallesttimeelementadecimalfractionwithonedigit.
a) Aspecifichour,minuteandsecondandadecimalfractionofthesecondBasicformat: hhmmss,ss Example: 232050,5Extendedformat: hh:mm:ss,ss Example: 23:20:50,5
b) AspecifichourandminuteandadecimalfractionoftheminuteBasicformat: hhmm,mm Example: 2320,8Extendedformat: hh:mm,mm Example: 23:20,8
c) AspecifichourandadecimalfractionofthehourBasicformat: hh,hh Example: 23,3Extendedformat: notapplicable
NOTE 4.2.2.4 includes the definition of representations that have both reduced accuracy and a decimalfraction.
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4.2.2.5 Representationswithtimedesignator
Inexpressionsof local time,applicationsmayput the timedesignator [T] immediately in frontof therepresentationsdefinedin4.2.2.2through4.2.2.4.
If the local time is represented ina context thatdoesnot clearly identifya local timeexpression, thetimedesignator[T]shallbeusedimmediatelyinfrontoftherepresentationsdefinedin4.2.2.2through4.2.2.4.
4.2.3 Beginning/endoftheday
Thecompleterepresentationsinbasicandextendedformatfortheendofthedayandthebeginningofthefollowingday,inaccordancewith4.2.2,shallbeexpressedasfollows:
Basicformat Extendedformat
000000 00:00:00 Beginningofday
240000 24:00:00 Endofday
Therepresentationsmayhavereducedaccuracyinaccordancewith4.2.2.3ormaybedesignatedasatimeexpressioninaccordancewith4.2.2.5.Torepresentthestartorendofaday,therepresentationsmaybeexpandedwithadecimalfractioncontainingonlyzerosinaccordancewith4.2.2.4.
NOTE1 Theendofonecalendarday[24:00]coincideswith[00:00]at thestartof thenextcalendarday,e.g.[24:00]on12April1985isthesameas[00:00]on13April1985.
NOTE2 Theendofdayrepresentations,where[hh]hasthevalue[24],shallbeusedonlytorepresenttheendofdaywithinatimeintervalinaccordancewith4.4orrecurringtimeintervalinaccordancewith4.5.
NOTE3 Theendofdayrepresentation,where[hh]hasavalueof[24],shallnotbeusedforasingletimepoint.
4.2.4 UTCofday
ToexpressUTCofday therepresentationsspecified in4.2.2.2 through4.2.2.4shallbeused, followedimmediately,withoutspace,bytheUTCdesignator[Z].TheexamplesbelowarecompleteandreducedaccuracyrepresentationsoftheUTCofday20minutesand30secondspast23hours:
Basicformat: hhmmssZ Example: 232030Z hhmmZ 2320Z hhZ 23Z
Extendedformat: hh:mm:ssZ Example: 23:20:30Z hh:mmZ 23:20Z notapplicable
4.2.5 LocaltimeandCoordinatedUniversalTime(UTC)
4.2.5.1 DifferencebetweenlocaltimeandUTCofday
WhenitisrequiredtoindicatethedifferencebetweenlocaltimeandUTCofday,therepresentationofthedifferencecanbeexpressed inhoursandminutes,orhoursonly. Itshallbeexpressedaspositive(i.e.withtheleadingplussign[+])ifthelocaltimeisaheadoforequaltoUTCofdayandasnegative(i.e. with the leading minus sign [-]) if it is behind UTC of day. The minutes time element of thedifferencemayonlybeomittedifthedifferencebetweenthetimescalesisexactlyanintegralnumberofhours.
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Basicformat: ±hhmm Example: +0100 ±hh +01
Extendedformat: ±hh:mm Example: +01:00
Expressions of the difference between local time and UTC of day are a component in therepresentationsdefinedin4.2.5.2;theyshallnotbeusedasself-standingexpressions.
4.2.5.2 LocaltimeandthedifferencefromUTC
When it isrequiredto indicate local timeandthedifferencebetweenthe timescaleof local timeandUTC, the representation of the difference shall be appended to the representation of the local timefollowingimmediately,withoutspace,thelowestorder(extremeright-hand)timeelementofthelocaltime expression. The difference between the time scale of local time and UTC shall be expressed inhours-and-minutes,orhours-onlyindependentoftheaccuracyofthelocaltimeexpressionassociatedwithit.
Thecompleterepresentationofthetimeof27minutesand46secondspast15hourslocallyinGeneva(inwinteronehouraheadofUTC),andinNewYork(inwinterfivehoursbehindUTC),togetherwiththeindicationofthedifferencebetweenthetimescaleoflocaltimeandUTC,areusedasexamples.
Basicformat: hhmmss±hhmm Example: 152746+0100 152746−0500 hhmmss±hh 152746+01 152746−05
Extendedformat: hh:mm:ss±hh:mm Example: 15:27:46+01:00 15:27:46−05:00 hh:mm:ss±hh 15:27:46+01 15:27:46−05
Intheseexpressionsthelocaltimecomponentmayberepresentedwithreducedaccuracyasdefinedin4.2.2.3orwithdecimalfractionasdefinedin4.2.2.4.
4.3 Dateandtimeofday
4.3.1 General
Whentheapplicationdoesnotclearly identify theneedforonlyadateexpression(see4.1)oronlyatime of day expression (see 4.2), then a time point can be identified through a date and time of dayexpression.
4.3.2 Completerepresentations
Thetimeelementsofadateandtimeofdayexpressionshallbewritteninthefollowingsequence.
a) Forcalendardates:year–month–dayofthemonth–timedesignator–hour–minute–second–zonedesignator
b) Forordinaldates:year–dayoftheyear–timedesignator–hour–minute–second–zonedesignator
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c) Forweekdates:year–weekdesignator–week–dayoftheweek–timedesignator–hour–minute–second–zonedesignator
Thezonedesignatorisemptyifuseismadeoflocaltimeinaccordancewith4.2.2.2through4.2.2.4,itisthe UTC designator [Z] if use is made of UTC of day in accordance with 4.2.4 and it is thedifference-component if use is made of local time and the difference from UTC in accordance with4.2.5.2.
Thecharacter[T]shallbeusedastimedesignatortoindicatethestartoftherepresentationofthetimeofdaycomponent in theseexpressions.Thehyphen [-]and thecolon [:] shallbeused, inaccordancewith4.4.4,asseparatorswithinthedateandtimeofdayexpressions,respectively,whenrequired.
NOTE Bymutualagreementofthepartnersininformationinterchange,thecharacter[T]maybeomittedinapplicationswherethereisnoriskofconfusingadateandtimeofdayrepresentationwithothersdefinedinthisInternationalStandard.
Thefollowingareexamplesofcompleterepresentationsofdateandtimeofdayrepresentations:
Basicformat: YYYYMMDDThhmmss Example: 19850412T101530 YYYYMMDDThhmmssZ 19850412T101530Z YYYYMMDDThhmmss±hhmm 19850412T101530+0400 YYYYMMDDThhmmss±hh 19850412T101530+04
Extendedformat: YYYY-MM-DDThh:mm:ss Example: 1985-04-12T10:15:30 YYYY-MM-DDThh:mm:ssZ 1985-04-12T10:15:30Z YYYY-MM-DDThh:mm:ss±hh:mm 1985-04-12T10:15:30+04:00 YYYY-MM-DDThh:mm:ss±hh 1985-04-12T10:15:30+04
Wherecompleterepresentationsusingcalendardatesareshown,ordinaldates(4.1.3.2)orweekdates(4.1.4.2)maybesubstituted.
4.3.3 Representationsotherthancomplete
For reduced accuracy, decimal or expanded representations of date and time of day, any of therepresentations in 4.1.2 (calendar dates), 4.1.3 (ordinal dates) or 4.1.4 (week dates) followedimmediately by the time designator [T]may be combinedwith any of the representations in 4.2.2.2through 4.2.2.4 (local time), 4.2.4 (UTC of day) or 4.2.5.2 (local time and the difference from UTC)providedthat
a) therulesspecifiedinthosesectionsareapplied;
b) theresultingexpressiondoesnotqualifyasacompleterepresentationinaccordancewith4.3.2;
c) thedatecomponentshallnotberepresentedwithreducedaccuracy;
NOTE Thisexcludesalsothedaterepresentationsin4.1.2.4and4.1.4.4thatareexpandedandreduced.
d) theexpressionshall eitherbe completely inbasic format, inwhichcase theminimumnumberofseparatorsnecessary for therequiredexpression isused,orcompletely inextended format, inwhichcaseadditionalseparatorsshallbeusedinaccordancewith4.1and4.2.
The following are examples of reduced representations of combinations of date and time of dayrepresentations:
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a) CalendardateandlocaltimeBasicformat: YYYYMMDDThhmm Example: 19850412T1015Extendedformat: YYYY-MM-DDThh:mm Example: 1985-04-12T10:15
b) OrdinaldateandUTCofdayBasicformat: YYYYDDDThhmmZ Example: 1985102T1015ZExtendedformat: YYYY-DDDThh:mmZ Example: 1985-102T10:15Z
c) WeekdateandlocaltimeandthedifferencefromUTCBasicformat: YYYYWwwDThhmm±hhmm Example:1985W155T1015+0400Extendedformat: YYYY-Www-DThh:mm±hh Example: 1985-W15-5T10:15+04
4.4 Timeinterval
4.4.1 Meansofspecifyingtimeintervals
Atimeintervalshallbeexpressedinoneofthefollowingways:
a) byastartandanend;
b) byadurationandcontextinformation;
c) byastartandaduration;
d) byadurationandanend.
NOTE Thetimeintervalexpressedbymethodb)isnotfullydeterminedbytheinformationprovidedintheexpression.Itisassumedthat,whereneeded,additionalinformationtocompletelydeterminethetimeintervalisavailable from the context. It should however be noted that, although the expression contains only durationinformationitrepresentsa(notfullydetermined)timeinterval;notaduration.
4.4.2 Separatorsanddesignators
Atimeintervalisexpressedaccordingtothefollowingrules:
a) asolidus[/]shallbeusedtoseparatethetwocomponentsineachof4.4.1a),c)andd);
b) for 4.4.1 b), c) and d) the designator [P] shall precede, without space, the remainder of theexpressionofduration;
c) otherdesignatorsshallbeusedasshownin4.4.4and4.4.5below.
NOTE Incertainapplicationareasadoublehyphenisusedasaseparatorinsteadofasolidus.
4.4.3 Duration
4.4.3.1 General
Durationcanbeexpressedbyacombinationofcomponentswithaccurateduration(hour,minuteandsecond)andcomponentswithnominalduration(year,month,weekandday).Thetermdurationwillbeused todesignateexpressionscontainingcomponentswithaccurateduration,withnominalduration,orboth.
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NOTE1 Applications requiring accurate duration using the time unit day canmake use of the provisions ofISO31-1.
NOTE2 Duration is used as a component in representations of time intervals and recurring time intervals,representationofdurationassuchisnotfacilitatedbythisInternationalStandard.
4.4.3.2 Formatwithdesignators
Inexpressionsoftimeintervalorrecurringtimeinterval,durationcanberepresentedbyacombinationof components with designators. The number of years shall be followed by the designator [Y], thenumber of months by [M], the number of weeks by [W], and the number of days by [D]. The partincluding time components shall be preceded by the designator [T]; the number of hours shall befollowedby[H],thenumberofminutesby[M]andthenumberofsecondsby[S].Intheseexpressionsthedaycomponent[nnD]isexpressedasamultipleofthedurationofacalendarday.
Inbothbasicandextendedformatthecompleterepresentationoftheexpressionfordurationshallbe[PnnW]or[PnnYnnMnnDTnnHnnMnnS].
In these representations themaximum number of digits in a component needs to be agreed by thepartnersininformationinterchange.
Forreducedaccuracyordecimalrepresentationsofthisrepresentation,thefollowingrulesapply.
a) Ifnecessaryforaparticularapplication,thelowestordercomponentsmaybeomittedtorepresentdurationwithreducedaccuracy.
b) Ifnecessaryforaparticularapplication,thelowestordercomponentsmayhaveadecimalfraction.The decimal fraction shall be divided from the integer part by the decimal sign specified inISO31-0, i.e. thecomma[,]or fullstop[.].Of these, thecommais thepreferredsign.Thedecimalfraction shall at least have one digit, the maximum number of digits in the decimal componentneedstobeagreedbythepartners in informationinterchange. If themagnitudeofthenumberislessthanunity,thedecimalsignshallbeprecededbyazero(seeISO31-0).
c) Ifthenumberofyears,months,days,hours,minutesorsecondsinanyoftheseexpressionsequalszero,thenumberandthecorrespondingdesignatormaybeabsent;however,atleastonenumberanditsdesignatorshallbepresent.
d) Thedesignator[T]shallbeabsentifallofthetimecomponentsareabsent.
4.4.4 Completerepresentations
4.4.4.1 Representationsoftimeintervalsidentifiedbystartandend
Whentheapplicationidentifiestheneedforacompleterepresentationofatimeinterval,identifiedbyits start and its end, it shalluseanexpression inaccordancewith4.4.2 combiningany twocompletedateandtimeofdayrepresentationsasdefinedin4.3.2,providedthattheresultingexpressioniseitherconsistentlyinbasicformatorconsistentlyinextendedformat.
Basicformat: YYYYMMDDThhmmss/YYYYMMDDThhmmssExample: 19850412T232050/19850625T103000
Extendedformat: YYYY-MM-DDThh:mm:ss/YYYY-MM-DDThh:mm:ssExample: 1985-04-12T23:20:50/1985-06-25T10:30:00
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The examples represent a time interval beginning at 20minutes and 50seconds past 23hours on12April1985localtimeandendingat30minutespast10hourson25June1985localtime.
4.4.4.2 Representationsoftimeintervalsbydurationandcontextinformation
4.4.4.2.1 Formatwithdesignators
When an application identifies the need for a complete representation of a time interval through itsduration and context information, with duration in the format with designators, it shall use anexpressioninaccordancewith4.4.2usingacompletedurationrepresentationasdefinedin4.4.3.2.
Basicandextendedformat: PnnYnnMnnDTnnHnnMnnS PnnW
Example1: P2Y10M15DT10H30M20SExample2: P6W
Example1 represents a time interval with a duration of 2years, 10months, 15days, 10hours,30minutesand20seconds.Example2representsatimeintervalwithadurationofsixweeks.
4.4.4.2.2 Alternativeformat
If, by agreement, a complete representation of a time interval through its duration and contextinformation,withdurationinthealternativeformat,isused,theexpressionshallbeinaccordancewith4.4.2anduseacompletedurationrepresentationasdefinedin4.4.3.3.
Basicformat: PYYYYMMDDThhmmss Example: P00021015T103020Extendedformat: PYYYY-MM-DDThh:mm:ss Example: P0002-10-15T10:30:20
The examples represent a time interval with a duration of 2years, 10months, 15days, 10hours,30minutesand20seconds.
4.4.4.3 Representationsoftimeintervalidentifiedbystartandduration
Whentheapplicationidentifiestheneedforacompleterepresentationofatimeintervalidentifiedbyitsstartand itsduration, itshalluseanexpression inaccordancewith4.4.2,combininganycompletedateandtimeofdayrepresentationasdefinedin4.3.2withanycompleterepresentationofdurationasdefined in 4.4.3, provided that the resulting expression is either consistently in basic format orconsistentlyinextendedformat.
Basicformat: YYYYMMDDThhmmss/PnnYnnMnnDTnnHnnMnnS YYYYMMDDThhmmss/PYYYYMMDDThhmmss
Example: 19850412T232050/P1Y2M15DT12H30M0S 19850412T232050/P00010215T123000
Extendedformat: YYYY-MM-DDThh:mm:ss/PnnYnnMnnDTnnHnnMnnS YYYY-MM-DDThh:mm:ss/PYYYY-MM-DDThh:mm:ss
Example: 1985-04-12T23:20:50/P1Y2M15DT12H30M0S 1985-04-12T23:20:50/P0001-02-15T12:30:00
The examples represent a time interval of 1year, 2months, 15days, 12hours and 30minutes,beginningon12April1985at20minutesand50secondspast23hourslocaltime.
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4.4.4.4 Representationsoftimeintervalidentifiedbydurationandend
Whentheapplicationidentifiestheneedforacompleterepresentationofatimeintervalidentifiedbyitsdurationand its end, it shall useanexpression in accordancewith4.4.2, combiningany completerepresentationofthedurationasdefinedin4.4.3withanycompleterepresentationofdateandtimeofdayasdefinedin4.3.2,providedthattheresultingexpressioniseitherconsistentlyinbasicformatorconsistentlyinextendedformat.
Basicformat: PnnYnnMnnDTnnHnnMnnS/YYYYMMDDThhmmss PYYYYMMDDThhmmss/YYYYMMDDThhmmss
Example: P1Y2M15DT12H30M0S/19850412T232050 P00010215T123000/19850412T232050
Extendedformat: PnnYnnMnnDTnnHnnMnnS/YYYY-MM-DDThh:mm:ss PYYYY-MM-DDThh:mm:ss/YYYY-MM-DDThh:mm:ss
Example: P1Y2M15DT12H30M0S/1985-04-12T23:20:50 P0001-02-15T12:30:00/1985-04-12T23:20:50
The examples represent a time interval of 1year, 2months, 15days and 12hours and 30minutes,endingon12April1985at20minutesand50secondspast23hourslocaltime.
4.4.4.5 Othercompleterepresentations
In 4.4.4.1 through 4.4.4.4 representations are shown using calendar date, local time and durationcomponents.Othercompleterepresentationsarefoundbymakingthefollowingsubstitutionsineachof4.4.4.1through4.4.4.4:
— where representations using calendar dates in a time point component are shown, a completerepresentationofordinaldates(4.1.3)orofweekdates(4.1.4)maybesubstitutedforthecalendardate;
— where representations using local time in a time point component are shown, a completerepresentationofUTC(4.2.4)orlocaltimeandthedifferencefromUTC(4.2.5.2)maybesubstitutedforlocaltime;
— where representations using the expression [PnnYnnMnnDTnnHnnMnnS] are shown, theexpression[PnnW](4.4.3.2)maybesubstituted.
4.4.5 Representationsotherthancomplete
Arepresentationotherthancompleteofatimeintervalshallbeanexpressioninaccordancewith4.4.1and4.4.2,wheretimepointsarerepresentedinaccordancewith4.1,4.2or4.3andwheredurationisrepresentedinaccordancewith4.4.3.2or4.4.3.3,providedthat
a) therulesspecifiedinthosesectionsareapplied;
b) theresultisnotacompleterepresentationinaccordancewith4.4.4;and
c) theresultingexpressioniseitherconsistentlyinbasicformatorconsistentlyinextendedformat.
Theuseofarepresentationneedstobeagreedbythepartnersininformationinterchangeiftheuseofanyofitsconstituentpartsneedstobeagreedbythesepartners.
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Intherepresentationoftimeintervalsinaccordancewith4.4.1a),
— higher order time elements may be omitted from the expression following the solidus (i.e. therepresentationfor“endoftimeinterval”);insuchacaseitshallbeassumedthatthecorrespondingtimeelementsfromthe“startoftimeinterval”expressionapply(e.g.if[YYYYMM]areomitted,theendof the time interval is in thesamecalendaryearandcalendarmonthas thestartof the timeinterval);
— representations for timezonesandUTC includedwiththecomponentprecedingthesolidusshallbeassumedtoapplytothecomponentfollowingthesolidus,unlessacorrespondingalternativeisincluded.
4.5 Recurringtimeinterval
ISO8601Part2,section5“RepeatRulesforRecurringTimeIntervals”,extendsthissectionbyaddingaruleparttodefinetherepeatpatterntotheendoftherecurringtimeintervalstructure.
4.5.1 Meansofspecifyingrecurringtimeintervals
Arecurringtimeintervalshallbeexpressedinoneofthefollowingways.
a) Byanumberofrecurrences(optional),astartandanend.Thisrepresentsarecurringtimeintervalofwhichthefirsttimeinterval is identifiedbythelasttwocomponentsoftheexpressionandthenumberofrecurrencesbythefirstcomponent.Ifthenumberofrecurrencesisabsent,thenumberofoccurrencesisunbounded.
b) By a number of recurrences (optional), a duration and context. This represents a recurring timeinterval with the indicated duration for each time interval and with the indicated number ofrecurrences.Ifthenumberofrecurrencesisabsent,thenumberofoccurrencesisunbounded.
c) By a number of recurrences (optional), a start and a duration. This represents a recurring timeintervalofwhichthefirsttimeintervalisidentifiedbythelasttwocomponentsoftheexpressionandthenumberofrecurrencesbythefirstcomponent.Ifthenumberofrecurrencesisabsent,thenumberofoccurrencesisunbounded.
d) By a number of recurrences (optional), a duration and an end. This represents a recurring timeintervalofwhichthe last time interval is identifiedbythe last twocomponentsof theexpressionandthenumberofrecurrencesbythefirstcomponent.Ifthenumberofrecurrencesisabsent,thenumberofoccurrencesisunbounded.
4.5.2 Separatorsanddesignators
Arecursivetimeintervalisexpressedaccordingtothefollowingrule.
All representations start with the designator [R], followed, without spaces, by the number ofrecurrences, if present, followed, without spaces, by a solidus [/], followed, without spaces, by theexpressionofatimeintervalasper4.4.1.Fortherepresentations4.5.1a),4.5.1b),4.5.1c)and4.5.1d)thetimeintervalsasper4.4.1a),4.4.1b),4.4.1c)and4.4.1d)shallbeused,respectively.
4.5.3 Completerepresentations
Whentheapplication identifiestheneedforacompleterepresentationofarecurringtimeinterval, itshalluseanexpressioninaccordancewith4.5.2,combininganycompletetimeintervalrepresentationasdefinedin4.4.4withthenumberofrecurrences.
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Basicformat: Rn/YYYYMMDDThhmmss/YYYYMMDDThhmmss Rn/PnnYnnMnnDTnnHnnMnnS Rn/YYYYMMDDThhmmss/PnnYnnMnnDTnnHnnMnnS RnPnnYnnMnnDTnnHnnMnnS/YYYYMMDDThhmmss
Example: R12/19850412T232050/19850625T103000 R12/P2Y10M15DT10H30M20S R12/19850412T232050/P1Y2M15DT12H30M0S R12/P1Y2M15DT12H30M0S/19850412T232050
Extendedformat: Rn/YYYY-MM-DDThh:mm:ss/YYYY-MM-DDThh:mm:ss Rn/YYYY-MM-DDThh:mm:ss/PnYnMnDTnHnMnS Rn/PnnYnnMnnDTnnHnnMnnS/YYYY-MM-DDThh:mm:ss
Example: R12/l985-04-12T23:20:50/1985-06-25T10:30:00 R12/1985-04-12T23:20:50/P1Y2M15DT12H30M0S R12/P1Y2M15DT12H30M0S/1985-04-12T23:20:50
4.5.4 Representationsotherthancomplete
Arepresentationotherthancompleteofarecurringtimeintervalshallbeanexpressioninaccordancewith4.5.1and4.5.2,wherethetimeintervalisrepresentedinaccordancewith4.4.5.
5 Dateandtimeformatrepresentations
For thedescription of thedate and time representations in Clause4, usehas beenmadeof date andtime format representations in which characters are used either to represent themselves or torepresentothercharacters(typicallydigits)inthedateandtimerepresentations.
When an application identifies the need for the use of date and time format representations and byagreement of the communicating partners, the date and time format representations may beinterchanged.Aspecificdateandtimeformatrepresentationmayonlybeinterchanged
— iftheinterchangeofdataandtimeformatrepresentationsingeneralhasbeenagreed,and
— if applicable, if the interchangeofdate and time representationsderived from thedate and timeformatrepresentationhasbeenagreed.
EXAMPLE The date and time format representation [hh:mm:ss,sss] may only be interchanged if (1) theinterchangeofdateandtimeformatrepresentationshasbeenagreedand(2)theinterchangeoflocaltimewithadecimalfractioninthetimeelementsecondwiththreedecimaldigitshasbeenagreed.
Underliningof characters inadateand time format representation, to represent zeroormoreof theunderlinedcharacters in thederiveddateand timerepresentation (inaccordancewith3.4.2), isonlypermitted if, at the time of interchange of the date and time format representation, the number ofcharactersinthederiveddateandtimerepresentationisnotknown.
The date and time format representations permitted by this International Standard are specified inClause4.
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AnnexA(informative)
RelationshiptoISO2014,ISO2015,ISO2711,ISO3307andISO4031
In preparing the first edition of ISO2014 an examination was carried out of the potential uses ofall-numeric dates. The advantages of the descending order year-month-daywere found to outweighthose for the ascending order day-month-year, already established at that time inmany parts of theworld.
Theadvantagesofthedescendingorderwerefoundtoincludethefollowing:
— avoidance of the confusion between existing national conventions that use different systems ofascendingorder;
— theeasewithwhich thewholedatemaybe treatedasasinglenumeral for thepurposesof filingandclassification;
— arithmeticcalculation,particularlyincomputeruses;
— thepossibilityofcontinuingtheorderbyaddingdigitsforhour-minute-second.
Fortimes,useofthe24-hourtimekeepingsystemisnowsocommon(particularlyinviewofthewideavailability and use of digital watches) that separators to aid human interpretation are no longernecessarybutareincludedasoptions.
Thenaturaladditionof the lowerorder timedigits to thehigherorderdatedigits (seeabove)estab-lished the basic concept used in the preparation of this International Standard: that a point in timecould be uniquely represented in all-numeric form by a string of digits commencing with year andendingwithhour,minuteorsecond,dependingontheaccuracydesired.
From that concept representations of all other date and time values were logically derived; thus,ISO2014,ISO3307andISO4031havebeensuperseded.
Numbering of days and weeks in the year based on the Gregorian calendar is important in manycommercial applications.Methodsofnumbering theweeksof theyearvary fromcountry to country,and, therefore, for international tradeand for industrialplanningwithin internationalcompanies it isessential to use uniform numbering of weeks. ISO2015 and ISO2711 were prepared to meet theserequirements.
Theuniformnumberingofweeksnecessitatesauniquedesignationofthedayonwhichaweekbegins.For commercial purposes, i.e. accounting, planning and similar purposes for which a week numbermightbeused,Mondayhasbeenfoundthemostappropriateasthefirstdayoftheweek.
Identification of a particular date by means of ordinal dates (ISO2711) and by means of the weeknumbering system (ISO2015) were alternative methods that the basic concept of this InternationalStandardcouldalsoencompass;thus,ISO2015andISO2711havenowbeensuperseded.
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AnnexB(informative)
Examplesofrepresentations
B.1 Dateandtimerepresentations
B.1.1 Date
Calendardate—12April1985
Basicformat Extendedformat Explanation
19850412 1985-04-12 Complete
Ordinaldate—12April1985
Basicformat Extendedformat Explanation
1985102 1985-102 Complete
Weekdate—Friday12April1985
Basicformat Extendedformat Explanation
1985W155 1985-W15-5 Complete
Calendarweek—15thweekof1985
Basicformat Extendedformat Explanation
1985W15 1985-W15 Reducedaccuracy
Calendarmonth—April1985
Basicformat Extendedformat Explanation
1985-04 notapplicable Reducedaccuracy
Calendaryear—1985
Basicformat Extendedformat Explanation
1985 notapplicable Reducedaccuracy
Calendardate—
Basicformat Extendedformat Explanation
+0119850412 +011985-04-12 Expanded;sixdigitstorepresenttheyear.12April11985
−00020412 −0002-04-12 Expanded;fourdigitstorepresenttheyear.ThetwelfthofAprilinthesecondyear
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beforetheyear[0000]
B.1.2 Timeofday
Localtime—27minutesand46secondspast15hours
Basicformat Extendedformat Explanation
152746 15:27:46 Complete
1528 15:28 Reducedtohourandminute
15 notapplicable Reducedtohour
Localtimewithdecimalfractions—27minutesand35andahalfsecondpast15hours
Basicformat Extendedformat Explanation
152735,5 15:27:35,5 Complete, with decimalfraction
Thebeginningofaday
Basicformat Extendedformat Explanation
000000 00:00:00 Complete
0000 00:00 Hourandminuteonly
UTCofday—20minutesand30secondspast23hours
Basicformat Extendedformat Explanation
232030Z 23:20:30Z Complete
2320Z 23:20Z Reducedtohourandminute
23Z notapplicable Reducedtohour
LocaltimeandthedifferencefromUTC—27minutes46secondspast15hourslocallyinGeneva(onehouraheadofUTC)
Basicformat Extendedformat Explanation
152746+0100 15:27:46+01:00 Complete
152746+01 5:27:46+01 Time difference expressed in hoursonly
27minutes46secondspast15hourslocallyinNewYork(fivehoursbehindUTC)
Basicformat Extendedformat Explanation
152746-0500 15:27:46-05:00 Complete
152746-05 15:27:46-05 Time difference expressed in hoursonly
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B.1.3 Dateandtimeofday
Combinationsofcalendardateandlocaltime
Basicformat Extendedformat Explanation
19850412T101530 1985-04-12T10:15:30 Complete
CombinationsofordinaldateandUTCofday
Basicformat Extendedformat Explanation
1985102T235030Z 1985-102T23:50:30Z Complete
Combinationsofweekdateandlocaltime
Basicformat Extendedformat Explanation
1985W155T235030 1985-W15-5T23:50:30 Complete
B.1.4 Timeinterval
Definedbystartandend
A time interval starting at 20minutes and 50seconds past 23hours on 12April1985 and ending at30minutespast10hourson25June1985
Basicformat Extendedformat
19850412T232050/19850625T103000
1985-04-12T23:20:50/1985-06-25T10:30:00
Atimeintervalstartingat12April1985andendingon25June1985
Basicformat Extendedformat
19850412/0625 1985-04-12/06-25
Definedbydurationandcontext
Atimeintervalof2years,10months,15days,10hours,20minutesand30seconds
Basicformat Extendedformat
P2Y10M15DT10H20M30S notapplicable
P00021015T102030 P0002-10-15T10:20:30
Atimeintervalof1yearand6months
Basicformat Extendedformat
P1Y6M notapplicable
P0001-06 notapplicable
Atimeintervalofseventy-twohours
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Basicformat Extendedformat
PT72H notapplicable
Definedbystartandduration
A time interval of 1year, 2months, 15days and 12hours, beginning on 12April1985 at 20minutespast23hours
Basicformat Extendedformat
19850412T232000/P1Y2M15DT12H 1985-04-12T23:20:00/P1Y2M15DT12H
Definedbydurationandend
Atimeintervalof1year,2months,15daysand12hours,endingon12April1985at20minutespast23hours
Basicformat Extendedformat
P1Y2M15DT12H/19850412T232000 P1Y2M15DT12H/1985-04-12T23:20:00
B.1.5 Recurringtimeinterval
Definedbyrecurrences,durationandcontext
Fifteen recurrences of a time interval of 2years, 10months, 15days, 10hours, 20minutes and30seconds
Basicformat Extendedformat
R15/P2Y10M15DT10H20M30S notapplicable
Anunboundednumberofrecurrencesofatimeintervalof2years,15days,10hours,20minutesand30seconds
Basicformat Extendedformat
R/P00020015T102030 R/P0002-00-15T10:20:30
Tworecurrencesofatimeintervalof1yearand6months
Basicformat Extendedformat
R2/P1Y6M notapplicable
R2/P0001-06 notapplicable
Eightrecurrencesofatimeintervalof72hours
Basicformat Extendedformat
R8/PT72H notapplicable
Definedbyrecurrences,durationandend
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Anunboundednumberofoccurrencesofa time intervalof1year,2months,15daysand12hoursofwhichthelastoccurrenceendsat12April1985at20minutesand50secondspast23hours
Basicformat Extendedformat
R/P1Y2M15DT12H/19850412T232050
R/P1Y2M15DT12H/1985-04-12T23:20:50
B.2 Dateandtimeformatrepresentations
B.2.1 Date
Basicformat Extendedformat Explanation
YYYYMMDD YYYY-MM-DD completecalendardate
±YYYYYYDDD ±YYYYYY-DDD expanded ordinal date with two digitsadded
YYYYWww YYYY-Www weekdatewithaccuracyreducedtoweek
B.2.2 Timeofday
Basicformat Extendedformat Explanation
hhmmss hh:mm:ss completelocaltime
hhmm,mZ hh:mm,mZ reduced accuracy UTC of day with onedigitdecimalfractionforminutes
hhmm±hhmm hh:mm±hh:mm localtimeandthedifferencefromUTC—reducedaccuracy
B.2.3 Dateandtimeofday
Basicformat Extendedformat Explanation
YYYYDDDThhmm YYYY-DDDThh-mm completeordinaldate—reducedaccuracytimeofday
YYYYMMDDhhmm,m YYYY-MM-DDhh:mm,m
completecalendardate—reducedaccuracytimeofdaywithonedigitdecimalfractionforminute—notimedesignator
YYYYWwwDThh,hhZ YYYY-Www-DThh,hhZcompleteweekdate—reducedaccuracyUTCofdaywithtwodigitdecimalfractionforthehour
B.2.4 Timeinterval
Timeintervalbystartandend—completecalendardate—reducedaccuracyUTCofdaywithonedigitdecimalfraction
Basicformat Extendedformat
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YYYYMMDDThhmm,mZ/YYYYMMDDThhmm,m
YYYY-MM-DDThh:mm,mZ/YYYY-MM-DDThh:mm,m
Timeintervalbydurationandcontext—durationwithonlydaycomponentofthreedigits
Basicformat Extendedformat
PnnnD
Timeintervalbydurationandcontext—durationwithonlyhourcomponentwithoneormoredigitsintheintegralpartandoneormoredigitsinthedecimalpart
Basicformat Extendedformat
PTnn,nnH
B.2.5 Recurringtimeinterval
Time intervalbynumberof recurrences, start andend—recurrence specified through zeroormoredigits—startandendbyweekdatewithreducedaccuracy
Basicformat Extendedformat
Rn/YYYYWww/YYYYWww Rn/YYYY-Www/YYYY-Www
Time interval bynumber of recurrences, begin andduration— recurrence specified through zero ormoredigits—startbycompleteordinaldate—durationbyanumberofdays,wherethenumberhasatleastonedigit
Basicformat Extendedformat
Rn/YYYYDDD/PnnD Rn/YYYY-DDD/PnnD
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Bibliography
[1] ISO80000-1:2009,Quantitiesandunits--Part1:General
[2] ISO80000-3:2006,Quantitiesandunits--Part3:Spaceandtime
[3] ISO/IEC646:1991,Informationtechnology—ISO7-bitcodedcharactersetforinformationinterchange
[4] ISO19018:2004,Shipsandmarinetechnology—Terms,abbreviations,graphicalsymbolsandconceptsonnavigation
[5] IEC60050-112:2010,InternationalElectrotechnicalVocabulary—Part112:Quantitiesandunits
[6] IEC60050-113:2011,InternationalElectrotechnicalVocabulary—Part113:Physicsforelectrotechnology
[7] IEC60050-114:2011,InternationalElectrotechnicalVocabulary—Part114:Electrochemistry
[8] IEC60050-713:1998,InternationalElectrotechnicalVocabulary—Part713:Radiocommunications:transmitters,receivers,networksandoperation
[9] Rec.ITU-RTF.460-6(2002-02),Standard-frequencyandtime-signalemissions
[10] ITU-TRecommendationS.1(1993),InternationalTelegraphAlphabetNo.2