1980L0181—EN—09.02.2000—003.001—1
This document is meant purely as a documentation tool and the institutions do not assume any liability for its contents
►B COUNCILDIRECTIVE
of20December 1979
ontheapproximationofthelawsoftheMemberStatesrelatingtounitsofmeasurementandonthe
repealofDirective 71/354/EEC
(80/181/EEC)
(OJL39,15.2.1980,p.40)
Amendedby:
OfficialJournal
No page date
►M1CouncilDirective85/1/EECof18December1984 L2 11 3.1.1985
►M2CouncilDirective89/617/EECof27November1989 L357 28 7.12.1989
►M3Directive1999/103/ECoftheEuropeanParliamentandoftheCouncilof
24January2000 L34 17 9.2.2000
Correctedby:
►C1Corrigendum,OJL296,15.10.1981,p.52(80/181/EEC)
►C2Corrigendum,OJL104,29.4.2000,p.89(1999/103/EC)
►C3Corrigendum,OJL311,12.12.2000,p.50(1999/103/EC)
▼B
COUNCILDIRECTIVE
of20December 1979
on the approximationof the lawsofthe Member States relating to
unitsofmeasurementandontherepeal ofDirective 71/354/EEC
(80/181/EEC)
THECOUNCILOFTHEEUROPEANCOMMUNITIES,
Having regard to the Treaty establishing the European Economic
Community,andinparticluarArticle100thereof,
HavingregardtoCouncilDirective71/354/EECof18October1971on
theapproximationofthelawsoftheMemberStatesrelatingtounitsofmeasurement(
1),aslastamendedbyCouncilDirective76/770/EEC(2),
HavingregardtotheproposalfromtheCommission(3),
HavingregardtotheopinionoftheEuropeanParliament(4),
HavingregardtotheopinionoftheEconomicandSocialCommittee(5),
Whereasunitsofmeasurementareessentialintheuseofallmeasuring
instruments, to express measurements or any indication of quantity;whereasunitsofmeasurementareusedinmostfieldsofhumanactivity;
whereasitisnecessarytoensurethegreatestpossibleclarityintheiruse;
whereasitisthereforenecessarytomakerulesfortheirusewithintheCommunityforeconomic,publichealth,publicsafetyoradministrativepurposes;
Whereas,however,thereexistinternational conventionsoragreements
inthefieldofinternationaltransportwhichbindtheCommunityorthe
Member States; whereas these conventions or agreements have to berespected;
Whereasthelawswhichregulatetheuseofunitsofmeasurementinthe
MemberStatesdifferfromoneMemberStatetoanotherandasaresult
hinder trade; whereas, in these circumstances, it is necessary to
harmonize laws, regulations and administrative provisions in order toovercomesuchobstacles;
Whereas units of measurement are the subject of international
resolutionsadoptedbytheGeneralConferenceofWeightsandMeasures
(CGPM) set up by the Metre Convention signed in Paris on 20 May
1875,towhichalltheMemberStatesadhere;whereasthe‘InternationalSystemofUnits’(SI)wasdrawnupasaresultoftheseresolutions;
WhereastheCouncilon18October1971adoptedDirective71/354/EEC
on the approximation of the laws of the Member States in order to
eliminateobstaclestotradebyadoptingtheinternationalsystemofunits
at Community level; whereas Directive 71/354/EEC was amended bytheActofAccessionandbyDirective76/770/EEC;
Whereas these Community provisions have not overcome all the
obstacles in thisfield; whereas Directive 76/770/EEC provides forthereview before 31 December 1979 of the situation regarding units of
measurement, names and symbols listed in Chapter D of the Annex
thereto; whereas it has also proved necessary to review the situationregardingcertainotherunitsofmeasurement;
Whereasitisnecessary,inordertoavoidseriousdifficulties,toprovide
foratransitional periodduringwhichunitsofmeasurement whichare
notcompatiblewiththeinternationalsystemcanbephasedout;whereas
itisneverthelessessentialtoallowtheMemberStateswishingtodosoto bring into force as quickly as possible, on their territory, the1980L0181—EN—09.02.2000—003.001—2
(1) OJNoL243,29.10.1971,p.29.
(2) OJNoL262,27.9.1976,p.204.
(3) OJNoC81,28.3.1979,p.6.
(4) OJNoC127,21.5.1979,p.80.
(5) Opiniondeliveredon24/25October1979(notyetpublishedintheOfficial
Journal).
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provisionsofChapterIoftheAnnex;whereasitisthereforenecessary
to limit the duration of this transitional period at Community levelwhile,atthesametime,leavingtheMemberStatesfreetocurtailthat
period;
Whereas, during the transitional period, it is essential, particularly in
ordertoprotecttheconsumer,tomaintainaclearpositionontheuseofunitsofmeasurementintradebetweentheMemberStates;whereastheobligation on the Member States to allow use of supplementaryindications on products and equipment imported from other Member
Statesduringthistransitionalperiodseemstoservethispurposewell;
Whereas the systematic adoption of a solution of this kind for all
measuring instruments, including medical instruments, is however not
necessarily desirable; whereas the Member States should therefore beable to require that, on their territory, measuring instruments bearindicationsofquantityinasinglelegalunitofmeasurement;
Whereas this Directive does not affect the continued manufacture of
products already on the market; whereas it does, however, affect theplacing on the market and use of products and equipment bearing
indications of quantity in units of measurement which are no longer
legal units of measurement, when such products and equipment arenecessary to supplement or replace components or parts of suchproducts,equipmentandinstrumentsalreadyonthemarket;whereasitisthereforenecessaryforMemberStatestoauthorizetheplacingonthe
market and the use of such products and equipment to complete and
replacecomponents,evenwhentheybearindicationsofquantityinunitsofmeasurementwhicharenolongerlegalunitsofmeasurement,sothatproducts,equipmentorinstrumentsalreadyonthemarketmaycontinuetobeused;
WhereastheInternational Organization forStandardization (ISO)on1
March1974adoptedaninternationalstandardontherepresentation of
SI and other units for use in systems with limited sets of characters;
whereasitisadvisablefortheCommunitytoadoptthesolutionswhichhave already been approved on a wider international level by ISOStandard2955of1March1974;
WhereasCommunityprovisionsrelatingtounitsofmeasurementareto
befoundinseveralCommunitytexts;whereasthequestionofunitsofmeasurement is so important that it is essential that reference may be
made to a single Community text; whereas this Directive thereby
consolidates all the Community provisions on the subject and repealsDirective71/354/EEC,
HASADOPTEDTHISDIRECTIVE:
Article 1
The legal units of measurement within the meaning of this Directive
whichmustbeusedforexpressingquantitiesshallbe:
(a) thoselistedinChapterIoftheAnnex;
(b) thoselistedinChapterIIoftheAnnexonlyinthoseMemberStates
wheretheywereauthorizedon21April1973anduntiladatetobe
fixedbythoseStates;
(c) thoselistedinChapterIIIoftheAnnexonlyinthoseMemberStates
wheretheywereauthorizedon21April1973anduntiladatetobefixedbythoseStates.Thisdatemaynotbelaterthan31December1994;1980L0181—EN—09.02.2000—003.001—3
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(d) thoselistedinChapterIVoftheAnnexonlyinthoseMemberStates
wheretheywereauthorizedon21April1973anduntiladatetobefixedbythoseStates.Thisdatemaynotbelaterthan31December
1999.
Article 2
(a) The obligations arising under Article 1 relate to measuring
instruments used, measurements made and indications of quantity
expressed in units of measurement, for economic, public health,publicsafetyoradministrativepurposes.
(b) This Directive shall not affect the use in the field of air and sea
transportandrailtrafficofunits,otherthanthosemadecompulsoryby the Directive, which have been laid down in internationalconventionsoragreementsbindingtheCommunityortheMember
States.
Article 3
1. For the purposes of this Directive ‘supplementary indication’
means one or more indications of quantity expressed in units ofmeasurementnotcontainedinChapterIoftheAnnexaccompanyinganindicationofquantityexpressedinaunitcontainedinthatChapter.
2. The use of supplementary indications shall be authorized until
►
M331December2009 ◄.
3. However,MemberStatesmayrequirethatmeasuringinstruments
bearindicationsofquantityinasinglelegalunitofmeasurement.
4. The indication expressed in a unit of measurement listed in
ChapterIshallpredominate.Inparticular, theindicationsexpressedinunits of measurement not listed in Chapter I shall be expressed incharactersnolargerthanthoseofthecorrespondingindicationinunits
listedinChapterI.
Article 4
Theuseofunitsofmeasurement whicharenotorarenolongerlegal
shallbeauthorizedfor:
— productsandequipmentalreadyonthemarketand/orinserviceon
thedateonwhichthisDirectiveisadopted,
— components and parts of products and of equipment necessary to
supplementorreplacecomponentsorpartsoftheaboveproductsand
equipment.
However,theuseoflegalunitsofmeasurementmayberequiredforthe
indicatorsofmeasuringinstruments.
Article 5
International standardISO2955of ►M215May1983 ◄,‘Informa-
tion processing — Representations of SI and other units for use insystemswithlimitedcharactersets’shallapplyinthefieldcoveredbyparagraph1thereof.
Article 6
Directive71/354/EECshallberepealedon1October1981.1980L0181—EN—09.02.2000—003.001—4
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Article 6a
IssuesconcerningtheimplementationofthisDirectiveand,inparticular,
thematterofsupplementaryindicationsshallbefurtherexamined,andif
necessary the appropriate measures adopted in accordance with theprocedurereferredtoinArticle18ofCouncilDirective71/316/EEC(
1).
Article 7
(a) MemberStatesshalladoptandpublishbefore1July1981thelaws,
regulationsandadministrativeprovisionsnecessarytocomplywiththisDirectiveandshallinformtheCommissionthereof.
Theyshallapplytheseprovisionsfrom1October1981.
(b) As fromthe date of notification of this Directive, Mem ber States
shallalsoensurethattheCommissionisinformed,insufficienttimetoenableittosubmititscomments,ofanydraftlaws,regulationsor
administrative provisions which they intend to adopt in the field
coveredbythisDirective.
Article 8
ThisDirectiveisaddressedtotheMemberStates.1980L0181—EN—09.02.2000—003.001—5
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ANNEX
CHAPTERI
LEGALUNITSOFMEASUREMENTREFERREDTOINARTICLE1(a)
1. SIUNITSANDTHEIRDECIMALMULTIPLESANDSUBMULTIPLES
1.1.SIbaseunits
QuantityUnit
Name Symbol
Length metre m
Mass kilogramkgTime second s
Electriccurrent ampere A
Thermodynamictemperature kelvin K
Amountofsubstance mole mol
Luminousintensity candela cd
DefinitionsofSIbaseunits:
Unit of length
Ametreisthelengthofthepathtravelledinavacuumbylightduring
1/299792458seconds.
(SeventeenthCGPM(1983),Resolution1).
Unit of mass
The kilogram is the unit of mass; it is equal to the mass of the
internationalprototypeofthekilogram.
(ThirdCGPM(1901),page70oftheconferencereport).
Unit of time
The second is the duration of 9192631770 periods of the radiation
correspondingtothetransitionbetweenthetwohyperfinelevelsofthe
groundstateofthecaesium-133atom.
(ThirteenthCGPM(1967),resolution1).
Unit of electric currentTheampereisthatconstantcurrent,whichifmaintainedintwostraight
parallel conductors of infinite length, of negligible circular cross-
section,andplacedonemetreapartinvacuum,wouldproducebetween
thoseconductorsaforceequalto2×10
−7newtonpermetreoflength.
(CIPM(1946),resolution2,approvedbytheninthCGPM(1948)).
Unit of thermodynamic temperature
Thekelvin,unitofthermodynamictemperature,isthefraction1/273·16
ofthethermodynamictemperatureofthetriplepointofwater.
(ThirteenthCGPM(1967),resolution4).
Unit of amount of substance
(1) Themoleistheamountofsubstanceofasystemwhichcontainsas
manyelementary entities asthereareatomsin0·012kilogram of
carbon12.
(2) When themole isused,the elementary entities mustbespecified
and may be atoms, molecules, ions, electrons, other particles, or
specifiedgroupsofsuchparticles.
(FourteenthCGPM(1971),resolution3).1980L0181—EN—09.02.2000—003.001—6
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Unit of luminous intensity
Thecandelaistheluminousintensity,inagivendirection,ofasource
that emits monochromatic radiation of frequency of 540 × 1012hertz
and that has a radiant intensity in that direction of (1/683) watt per
steradian.
(SixteenthCGPM(1979),resolution3).
1.1.1.Special name and symbol of the SI unit of temperature for
expressingCelsiustemperature
QuantityUnit
Name Symbol
Celsiustemperature degreeCelsius ºC
Celsiustemperature ►C3t◄isdefinedasthedifference ►C3t=T
-T0◄betweenthetwothermodynamictemperatures ►C3T◄and
►C3T0◄where►C3T0◄=273,15K.Anintervalordifference
oftemperaturemaybeexpressedeitherinkelvinsorindegreesCelsius.
Theunit‘degreeCelsius’isequaltotheunit‘kelvin’.
1.2.OtherSIunits
1.2.1.SIsupplementaryunits
QuantityUnit
Name Symbol
Planeangle radian rad
Solidangle steradian sr
(EleventhCGPM,1960,resolution12).
DefinitionsofSIsupplementaryunits:
Unit of plane angle
Theradianistheanglebetweentworadiiofacirclewhich
cutoff onthe circumference anarc equal in length tothe
radius.
(InternationalstandardISO31—1:1992)Unit of solidangle
Thesteradianisthesolidangleofaconewhich,havingits
vertexinthecentreofasphere,cutsoffonthesurfaceof
the sphere an area equal to that of a square with sides of
lengthequaltotheradiusofthesphere.
(InternationalstandardISO31—1:1992)
1.2.2.SIderivedunits
Units derived coherently fromSI base units and SI
supplementary units are given as algebraic expressions in
theformofproductsofpowersoftheSIbaseunitsand/or
SIsupplementaryunitswithanumericalfactorequalto1.1980L0181—EN—09.02.2000—003.001—7
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1.2.3.SIderivedunitshavingnamesandsymbols
QuantityUnit Expression
Name SymbolInotherSI
unitsIntermsofSIbase
orsupplementary
units
Frequency hertz Hz s−1
Force newton N m·kg·s−2
Pressure,stress pascal Pa N·m−2m−1·kg·s−2
Energy,work;quantity
ofheat joule J N·mm2·kg·s−2
Power(1),radiantflux watt W J·s−1m2·kg·s−3
Quantityofelectricity,
electriccharge coulomb C s·A
Electricpotential,
potentialdifference,
electromotiveforce volt V W·A−1m2·kg·s−3·A−1
Electricresistance ohm ΩV·A−1m2·kg·s−3·A−2
Conductance siemens S A·V−1m−2·kg−1·s3·A2
Capacitance farad F C·V−1m−2·kg−1·s4·A2
Magneticflux weber Wb V·s m2·kg·s−2·A−1
Magneticfluxdensity tesla T Wb·m−2kg·s−2·A−1
Inductance henry H Wb·A−1m2·kg·s−2·A−2
Luminousflux lumen lm cd·sr
Illuminance lux lx lm·m−2m−2·cd·sr
Activity(ofaradio-
nuclide)becquer-
el Bq s−1
Absorbeddose,specificenergy
imparted,kerma,
absorbeddoseindex gray Gy J·kg
−1m2·s−2
Doseequivalent sievert Sv J·kg−1m2·s−2
(1) Special names for the unit of power: the name volt−ampere (symbol ‘VA’) when it is
usedtoexpresstheapparentpowerofalternatingelectriccurrent,andvar(symbol‘var’)when it isusedto expressreactive electric power.The ‘var’ isnotincludedin CGPMresolutions.
Units derived fromSI base units or supplem entary units
maybeexpressedintermsoftheunitslistedinChapter1.
In particular, SI derived units may be expressed by the
special names and symbols given in the above table; for
example,theSIunitofdynamicviscositymaybeexpressed
asm−1·kg·s−1orN·s·m−2orPa·s.
1.3.Prefixes and their symbols used to designate certain decimal
multiplesandsubmultiples
Factor Prefix Symbol
1024yotta Y
1021zetta Z
1018exa E
1015peta P
1012tera T
109giga G
106mega M1980L0181—EN—09.02.2000—003.001—8
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Factor Prefix Symbol
103kilo ►C2k◄
102hecto ►C2h◄
101deca da
10-1deci d
10-2centi c
10-3milli m
10-6micro µ
10-9nano n
10-12pico p
10-15femto f
10-18atto a
10-21zepto z
10-24yocto y
Thenamesandsymbolsofthedecimalmultiplesandsubmultiples
oftheunitofmassareformedbyattachingprefixestotheword
‘gram’andtheirsymbolstothesymbol‘g’.
Where a derived unit is expressed as a fraction, its decimal
multiples and submultiples may be designated by attaching a
prefix to units in the numerator or the denominator, or in both
theseparts.
Compound prefixes, that is to say prefixes formed by the
juxtapositionofseveraloftheaboveprefixes,maynotbeused.
1.4.Special authorized names and symbols of decimal multiples
andsubmultiplesofSIunits
QuantityUnit
Name Symbol Value
Volume litre 1orL(1)1 l = 1 d m3=10−3m3
Mass tonne t 1t=1Mg=103kg
Pressure,stress bar bar(2) 1bar=105Pa
(1) Thetwosymbols‘I’and‘L’maybeusedforthelitreunit.
(SixteenthCGPM(1979),resolution6).
(2) UnitlistedintheInternationalBureauofWeightsandMeasuresbookletasamongtheunitstobe
permittedtemporarily.
Note:Theprefixesandtheirsymbolslistedin1.3maybeusedin
conjunctionwiththeunitsandsymbolscontainedinTable
1.4.1980L0181—EN—09.02.2000—003.001—9
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2. UNITSWHICHAREDEFINEDONTHEBASISOFSIUNITSBUT
ARENOTDECIMALMULTIPLESORSUBMULTIPLESTHEREOF
QuantityUnit
Name Symbol Value
Planeangle revolution*(1)(a) 1revolution=2 πrad
grade*orgon* gon* 1gon ¼π
200rad
degree º 1º ¼π
180rad
minuteofangle ′ 10¼π
10800rad
secondofangle ″ 100¼π
648000rad
Time minute min 1min=60s
hour h 1h=3600s
day d 1d=86400s
(1) Thecharacter(*)afteraunitnameorsymbolindicatesthatitdoesnotappearinthelistsdrawnupby
theCGPM,CIPMoBIPM.ThisappliestothewholeofthisAnnex.
(a) Nointernationalsymbolexists.
Note:Theprefixeslistedin1.3mayonlybeusedinconjunctionwith
thenames‘grade’or‘gon’andthesymbol‘gon’.
3. UNITS USED WITH THE SI, WHOSE VALUES IN SI ARE
OBTAINEDEXPERIMENTALLY
QuantityUnit
Name Symbol Definition
Energy Electronvolt eV The electron volt is the
kinetic energy acquired by
an electron in passing
through a potential differ-
enceof1voltinvaccum
Mass Unifiedatomicmassunit u The unified atomic mass
units is equal to 1/12 of
the mass of an atom of the
nuclide12C.
Note:The prefixes and their symbols listed in 1.3 may be used in
conjunctionwiththesetwounitsandwiththeirsymbols.
4. UNITS AND NAMES OF UNITS PERMITTED IN SPECIALIZED
FIELDSONLY
QuantityUnit
Name Symbol Value
Vergencyofoptical
systems dioptre* 1dioptre=1m−1
Massofpreciousstones metriccarat 1metriccarat=2×10−4kg
Areaoffarmlandand
buildingland are a 1a=102m2
Massperunitlengthoftextileyarnsandthreads tex* tex* 1tex=10
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QuantityUnit
Name Symbol Value
Bloodpressureandpres-
sureofotherbodyfluidsMillimetreof
mercury mmHg(*) 1mmHg=133,322Pa
Effectivecross-sectional
area Barn b 1b=10−28m2
Note:►M1Theprefixesandtheirsymbolslistedin1.3maybeused
in conjunction with the above units and symbols, with the
exception of the millimetre of mercury and its symbol. The
multipleof102ais,however,calleda‘hectare’. ◄
5. COMPOUNDUNITS
CombinationsoftheunitslistedinChapterIformcompoundunits.
CHAPTERII
LEGALUNITSOFMEASUREMENTREFERREDTOINARTICLE1(b),
PERMITTEDFORSPECIFICUSESONLY
FieldofapplicationUnit
Name Approximatevalue Symbol
Roadtrafficsigns,distanceand
speedmeasurementmile 1mile= 1609m mile
yard 1yd= 0,9144myd
foot 1ft= 0,3048mft
inch 1in= 2,54×10−2min
Dispense of draught beer and
cider; milk in returnable
containerspint 1pt= 0,5683×10−3m3pt
Landregistration acre 1ac= 4047m2ac
Transactioninpreciousmetals troyounce 1oztr= 31,10×10−3kg oztr
UntilthedatetobefixedunderArticle1(b),theunitslistedinthisChapter
may be combined with each other or whith those in Chapter I to form
compoundunits.
CHAPTERIII
LEGALUNITSOFMEASUREMENTREFERREDTOINARTICLE1(c)
QUANTITIES, NAMES OF UNITS, SYMBOLS AND APPROXIMATE
VALUES
Length
inch 1in =2·54×10−2m
foot 1ft =0·3048m
mile 1mile =1609myard 1yard =0·9144m
Area
squarefoot 1sqft =0·929×10
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acre 1ac =4047m2
squareyard 1sqyd =0·8361m2
Volume
fluidounce 1floz =28·41×10−6m3
gill 1gill =0·1421×10−3m3
pint 1pt =0·5683×10−3m3
quart 1qt =1·137×10−3m3
gallon 1gal =4·546×10−3m3
Massounce(avoirdupois) 1oz =28·35×10
−3kg
troyounce 1oztr =31·10×10−3kg
pound 1lb =0·4536kg
Energy
therm1therm =105·506×106J
UntilthedatetobefixedunderArticle1(c),theunitslistedinChapterIIImay
be combined with each other or with those in Chapter I to form compound
units.
CHAPTERIV
LEGALUNITSOFMEASUREMENTREFERREDTOINARTICLEI(d),
PERMITTEDINSPECIALIZEDFIELDSONLY
FieldofapplicationUnit
Name Approximatevalue Symbol
Marinenavigation fathom1fm = 1,829mfm
Beer,cider,waters,lemonades
and fruit juices in returnable
containerspint 1pt= 0,5683×10−3m3pt
fluidounce 1floz= 28,41×10−6m3fl.oz
Spiritdrinks gill 1gill= 0,142×10−3m3gill
Goodssoldlooseinbulk ounce
(avoirdupois)1oz= 28,35×10−3kg oz
pound 1lb= 0,4536kg lb
Gassupply therm1therm = 105,506×106J therm
UntilthedatetobefixedunderArticle1(d),theunitslistedinthisChapter
may be combined with each other or with those in Chapter I to form
compoundunits.1980L0181—EN—09.02.2000—003.001—12
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