Key Benefits:
CHAIR OF THE COUNCIL OF MINISTERS
Proposal for Law No. 17 /XI/1.
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Exhibition of Motives
In 1789, the Decimal Metric System was created that initially adopted three units
basic measurement: the meter, the liter and the kilogram. Afterwards, this system was
devoted internationally through the "Metro Convention", diplomatic treaty
celebrated in Paris on May 20, 1875, by 17 countries, including Portugal, which
determined the realization of the iridiated platinum patterns of the meter and the kilogram and
distribution of copies to member countries.
In the meantime, scientific and technological development has gone on to demand measurements each time
more accurate and in many other fields, having been successively approved new
units and other rules by the General Conference of Weights and Measures (CGPM), the organ of
four-year decision of the Metro Convention. In 1960, the decimal metric system was
designated International System of Units (SI).
SI defines the names, symbols and definitions of the units, as well as the prefixes and
the symbols of the multiples and the submultiples of the same units, and contemplates yet
recommendations for writing and for the use of the symbols approved by the CGPM.
SI was adopted in Portugal through the Decree-Law No. 427/83 of December 7,
changed by Decree-Law No. 320/84 of October 1, subsequently revoked by the
Decree-Law No. 238/94 of September 19, as amended by Decree-Law No 254/2002, of
November 22, which has approved again the system of legal measuring units and transposed
for the national legal order Directive No 80 /181/CEE, of the Council, of 20 of
December 1979, on the approximation of the laws of the Member States
relating to the units of measure, as amended by Council Directive No 85 /1/CEE, of
December 18, 1984, by Council Directive No 89 /617/CEE of 27 of
November 1989, and by Directive No 1999 /103/CE, of the European Parliament and of the
Council, of January 24, 2000.
CHAIR OF THE COUNCIL OF MINISTERS
Proposal for Law No. 17 /XI/1.
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The Directive No 2009 /3/CE of the European Parliament and of the Council of March 11 of
2009, introduces amendments to the above mentioned Directive No 80 /181/CEE, so it is justified to
revision of the national legislative framework.
They thus highlight the continuity of permission from the use of supplementary indications
in addition to the legal units set out in Chapter I of the Annex Directive
n. 80 /181/CEE, without a definite deadline; and, the inclusion of the decisions of the CGPM, concerning the
elimination of the class of SI supplementary units, as a separate class, à
interpretation of "radiano" and "terradian" units as non-dimension SI units, à
introduction of the SI "katal" unit of measurement to express the catalytic activity and the
introduction of a note on the definition of the "kelvin" to eliminate one of the largest sources
of the variation observed between realizations of the triple point of water.
They have finally been updated the definitions and the relevant SI units of
mode to be harmonized with the last SI edition, thus waiting to facilitate the use
by the different economic operators and by the Portuguese society in general of the System
Legal of the units of measurement in force.
Thus:
Under the terms of the paragraph d) of Article 197 (1) of the Constitution, the Government presents to the
Assembly of the Republic the following proposal for a law:
Article 1.
Subject
The Government is granted permission to change the system of statutory units of measure,
approved by Decree-Law No. 238/94 of September 19, transposing to the order
legal internal to Directive No 2009 /3/CE, of the European Parliament and of the Council, of 11
of March 2009.
CHAIR OF THE COUNCIL OF MINISTERS
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Article 2.
Sense and extension
The sense and extent of the present authorisation are those that result from the transposition to
internal legal order of Directive No 2009 /3/CE, of the European Parliament and of the
Council of March 11, 2009 amending Council Directive No 80 /181/CEE of the Council,
of November 27, 1989 on the approximation of the laws of the Member States
relating to the units of measurement, in particular:
a) Permission of the use of supplementary indications, for indefinite time,
in addition to the established legal units;
b) Elimination of the class of supplementary units of the International System of
Units (SI), as a separate class;
c) Interpretation of "radiano" and "Searthadian" units, as units (SI) without
dimension;
d) Introduction of the SI "katal" unit of measure to express the activity
catalytic;
e) Introduction of a note on the definition of the "kelvin" to eliminate one of the
greater sources of the observed variation between realizations of the triple point of water.
Article 3.
Duration
The present legislative authorization has the duration of 90 days.
Seen and approved in Council of Ministers of April 1, 2010
The Prime Minister
CHAIR OF THE COUNCIL OF MINISTERS
Proposal for Law No. 17 /XI/1.
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The Minister of the Presidency
The Minister of Parliamentary Affairs
CHAIR OF THE COUNCIL OF MINISTERS
Proposal for Law No. 17 /XI/1.
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The Metro Convention, signed in Paris, on May 20, 1875 and of which Portugal is
signatory, gave rise to the Medical System, which, as of 1960, went on to be designated
by the General Conference of Weights and Measures (CGPM) as the International System of
Units (SI).
SI is the system through which are determined the names, symbols and definitions of the
units, as well as the prefixes and symbols of the multiples and submultiples of the same
units, and which contemplates the recommendations for writing and for the use of the symbols
approved by the CGPM.
Portugal has adopted the system of units of measurement through Decree-Law No. 427/83, 7
of December, as amended by Decree-Law No. 320/84 of October 1. That decree-law
was subsequently revoked by the Decree-Law No. 238/94 of September 19, which approved
the new system of statutory units of measure and transposed into the national legal order a
Council Directive No 80 /181/CEE of December 20, 1979 on the
approximation of the laws of the Member States relating to the units of measurement,
amended by Council Directive No 85 /1/CEE of December 18, 1984 by the
Council Directive 89 /617/CEE of the Council of November 27, 1989 and by Directive n
1999 /103/CE, of the European Parliament and of the Council, of January 24 of
2000.Decorridos about sixteen years on the publication of the Decree-Law No. 238 / 94,
changed by Decree-Law No. 254/2002 of November 22, becomes necessary
appropriate the national legislation applicable to the units of measure to Community legislation,
Proceeding to the transposition of Directive No 2009 /3/CE, the European Parliament and the
Council, of March 11, 2009.
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They thus highlight the permission of the use of supplementary indications, in addition to the
legal units set out in Chapter I of Annex Directive No 80 /181/CEE of the
Advice and used in some Member States of the European Union, without any
temporal constraint; and, the inclusion of the decisions of the CGPM, concerning the elimination of the class of
supplementary units SI, as a separate class, to the interpretation of the units
"radiano" and "terradian" as non-dimension SI units, to the introduction of the unit of
measure of the SI "katal" to express the catalytic activity and the introduction of a note on
the definition of the "kelvin" to eliminate one of the largest sources of the observed variation between
realizations of the triple point of water.
They have finally been updated the definitions and the relevant SI units of
mode to be harmonized with the last SI edition, thus waiting to facilitate the use
by the different economic operators and by the Portuguese society in general of the System
Legal of the units of measurement in force.
The self-governing bodies of the Autonomous Regions were heard.
Thus:
In the use of the legislative authorization granted by Law No, and of the points a) and b) from the
n Article 198 (1) of the Constitution, the Government decrees the following:
Article 1.
Subject
The present decree-law changes the system of statutory units of measure, approved by the
Decree-Law No. 238/94 of September 19, transposing to the internal legal order a
Directive No 2009 /3/CE of the European Parliament and of the Council of March 11 of
2009, amending Directive No 80 /181/CEE, of the Council of December 20, 1979,
on the approximation of the laws of the Member States relating to the units of
measure.
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Article 2.
Amendment to Decree-Law No 238/94 of September 19
Articles 1, 2, 3, 5, 6, and 7 and 7 of the Decree-Law No. 238/94 of September 19,
changed by Decree-Law No. 254/2002 of November 22, they go on to the following
wording:
" Article 1.
[...]
1-The system of statutory units of measure, designated by the General Conference
of Weights and Measures (CGPM) as the International System of Units
(SI), is applicable throughout the national territory.
2-The names, symbols and definitions of the units, the prefixes and symbols of the
multiples and submultiples of the same units, and the recommendations for the
writing and for the use of the symbols, approved by the CGPM, are listed
of the annex to this decree-law, of which it is an integral part.
Article 2.
[...]
1-The use of supplementary indications is permitted.
2-It is understood that there is supplementary indication when an indication
expressed in a constant unit of the annex to the present decree-law is
accompanied by one or more indications expressed in other units.
3-A The indication expressed in a unit of measure constant in the Annex to
present decree-law prevails on the supplementary indications.
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Article 3.
[...]
1-A The use of units of measure deemed non-legal shall be authorised:
a) For the products and equipment placed on the market or in
service on a date prior to the entry into force of this Decree-
law;
b) For parts and parts of products and equipment that complete
or replace the parts and parts of products and equipment
provided for in the preceding paragraph.
2-[...].
Article 4.
[...]
1-The provisions of the preceding Articles covers the measuring instruments, the
measurements carried out and the units of magnitude expressed in units of
measure, in the commercial circuit, in the areas of health, safety
public, teaching and operations of an administrative and tax nature.
2-This decree-law shall not affect the use, in the field of navigation
air and sea and traffic by rail, of units of measurement
several of the statutory units of measure, provided for by conventions or
international agreements binding on the European Union or Portugal.
Article 5.
Standards of the statutory units of measurement
It competes with the Portuguese Institute of Quality, I. P., (IPQ, I. P.), approve, de
agreement with the one set out in this decree-law, the standards that carry out the
legal units of measure.
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Article 6.
[...]
1-Compete to the Food and Economic Security Authority (ASAE)
scrutinise compliance with this decree-law, without prejudice to the
competencies assigned by law to other entities.
2-Of the verified offences is raised self-news, pursuant to the
applicable provisions.
3-A The instruction of counterordinance processes competes with ASAE, to whom
they must be sent the autos relating to offences verified by others
entities.
Article 7.
[...]
1-A use of unauthorised measure units, in the terms of the article
3., constitutes counterordinance punishable with fine of € 25 a € 2500 if the
infractor for a natural person and up to € 30000 if it is a person
collective.
2-A The application of the fine laid down in the preceding paragraph shall compete with the Commission of
Application of Coimas in Economic and Advertising Matters
(CACMEP).
3-The product of the applied fines reverses in:
a) 60% for the State;
b) 15% for the ASAE;
c) 15% for the IPQ, I. Q.;
d) 10% for CACMEP. "
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Article 3.
Amendment to the Annex to Decree-Law No 238/94 of September 19
The Annex referred to in Article 1 of the Decree-Law No 238/94 of September 19,
amended by Decree-Law No. 254/2002 of November 22 is replaced by the wording
constant in Annex I to the present decree-law, of which it is an integral part.
Article 4.
Addition to the Decree-Law No. 238/94, of September 19
It is added to Decree-Law No. 238/94 of September 19, as amended by the Decree-Law
n ° 254/2002 of November 22, Article 7, with the following wording:
" Article 7.
Autonomous Regions
The acts and procedures necessary for the implementation of this decree-law
in the Autonomous Regions of the Azores and Madeira compete with the entities of the
respective regional administrations with assignments and competences in the
subjects in question. "
Article 5.
Republication
It is republished, in Annex II to the present decree-law, of which it is an integral part, the
Decree-Law No. 238/94 of September 19, with the current wording.
Seen and approved in Council of Ministers of
The Prime Minister
CHAIR OF THE COUNCIL OF MINISTERS
Proposal for Law No. 17 /XI/1.
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The Minister of State and Foreign Affairs
The Minister of Justice
The Minister of Economy, Innovation and Development
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Proposal for Law No. 17 /XI/1.
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Annex I
(referred to in Article 3)
Attachment
Units of legal measures referred to in Article 1.
1-UNITS SI AND THEIR MULTIPLES AND SUBMULTIPLES
1.1-base units of SI:
[...].
Definitions of the SI base units:
Unit of length (meter)
[...].
Unit of mass (kilogram)
[...].
Unit of time (second)
[...].
Electric current unit (ampere)
[...].
Thermodynamic temperature unit (kelvin)
The kelvin, thermodynamic temperature unit, is the fraction 1/273, to 16 of the temperature
thermodynamics of the triple point of water.
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This definition relates to water with isotopic composition defined by the following ratios
of quantity of matter: 0.000 155 76 mole of 2H per mole of 1H, 0.000 379 9 mole of
17th by mole of 16th and 0.002 005 2 mole of 18th by mole of 16th.
(13ª CGPM of 1967/68-Resolution No. 4 and 23 th CGPM of 2007-Resolution No. 10)
Quantity unit of matter (mole)
(1) The mole is the amount of matter of a system containing so many elementary entities
how many of the atoms that exist in 0.012 kilogram of carbon 12; their symbol is
"mol".
(2) When using the mole, the elementary entities must be specified and may be
atoms, molecules, ions, electrons, other specified particles or groupings of such
particles.
(14ª CGPM of 1971-Resolution No. 3)
Luminous intensity unit (candela)
The candela is the luminous intensity, in a given direction, of a source that emits a
monochromatic frequency 540 frequency 1012 inherited 1012 hertz and whose energy intensity in that
direction is 1/683 watt per esteradian.
(16ª CGPM of 1979-Resolution No. 3)
1.1.1 Name and special symbol of the SI unit of temperature in the case of temperature
Celsius
[...].
The temperature Celsius, of symbol t , is defined by the difference t = T The T 0 between two
thermodynamic temperatures T and T 0 with T 0 = 273.15 K, freezing point of water. A
interval or a difference in temperature can be expressed either in kelvin or in
degree Celsius. The degree Celsius unit is equal to the kelvin unit.
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1.2-Derived SI Units
The coherent derivative units of the base SI units are given by expressions
algebraic in the form of power products of the base SI units with a factor
numerical equal to 1.
1.2.1 Units expressed from the base units
Derivative grandeur
SI derivative unit
Symbol Name
surface square meter m2
cubic meter volume m3
speed meter per second m/s
metro acceleration per second square m/s2
wave number meter at power minus 1 m-1
mass voldamic mass kilogram per cubic metre kg/m3
volume mass volume cubic metre per kilogram m3/kg
ampere current density per square meter A/m2
magnetic field ampere per metre A/m
concentration (of quantity of matter) mole per cubic metre mol / m3
luminous candela luminance per square metre cd / m2
refractive index (the number) a 1 (a)
relative permeability (the number) a 1 (a)
(a) In general, the symbol "1" with a numerical value is not used.
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1.2.2 Units with special names and symbols
The special names and particular symbols assigned to certain units
derivates allow to express in a condensed form frequently used units.
Greatness
SI derivative unit
Symbol Name
Expression in
other units
SI
Expression in
base SI units
angle plane radiane (a) rad 1 (b) m/m
solid angle terradian (a) sr (b) 1 (b) m2/m2
frequency hertz Hz s-1
force newton N m kg kg s-2
pressure, tension pascal Pa N/m2 m-1 kg of s-2
energy, work, amount of heat joule J N heating m m2 heating kg s-2
power (c), energy flow watt W J/s m2 kg of kg s-3
electric charge, amount of electricity coulomb C s lacking A
difference of electric potential, strength
electromoGuideline volt V W/A m2 kg of s-3 lacking s-3
electrical capacity farad F C/V m-2 m-2-s4-s4
electrical resistance ohm resistant V/A m2 resistant kg s-3 resistant A-2
electrical conductance siemens S A/V m-2 weight kg-1 weight s3 s3 A2
magnetic induction flux, magnetic flux weber Wb V kg s m2 kg of s-2 kg A-1
magnetic induction, flow density
magnetic tesla T Wb/m2 kg s-2 kg A-1
inductance henry H Wb/A m2 kg of s-2 weight s-2
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temperature Celsius degree Celsius (d) ºC K
luminous flux lumen lm cd absorption sr (b) cd
illuminance lux lx lm/m2 m-2 slower cd
activity of a radionucleido becquerel Bq s-1
absorbed dose, manly energy, kerma gray Gy J/kg m2 exhaust s-2
equivalent of dose, dose equivalent
environmental, directional dose equivalent,
individual dose equivalent
sievert Sv J/kg m2 s-2
catalytic activity katal kat s-1 driven mol
(a) The radian and the terradian can be useful in the expressions of the derived units, to distinguish granal
of a different nature with the same dimension. The examples of this use are listed in point 1.2.3.
(b) Only if it employs, in practice and when it is useful, the symbols rad and sr, but the derivative unit "1" is usually
omitted in combination with a numerical value. In photometry, it remains in general the name and symbol of the
sterradian, sr, in the expression of the units.
(c) Special names of the power unit; the name "voltampere" (symbol "VA"), to express the power
apparent from the alternating electric current, and the name "var" (symbol "var"), to express the electrical power
reactive. The names "voltampere" and "var" are not included in the resolutions of the CGPM.
(d) This unit may be used in association with SI prefixes, as for example to express the
submultiples miligrau Celsius, mºC.
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1.2.3 Examples of SI-derived units whose name and symbol contain units
derivative of SI with special names and symbols
Greatness
SI derivative unit
Name Symbol Expression in SI units
of base
dynamic viscosity pascal second Pa spokesman s m-1 kg of kg s-1
moment of force newton metro N occasion m m2 kg kg s-2
surface tension newton per meter N/m kg s-2
radian angular velocity per second rad / s m m-1 crushed s-1 = s-1
radian angular acceleration per second squared rad / s2 m crushed m-1 s-2 = s-2
thermal flux density, irradiance watt per square metre W/m2 kg s-3
thermal capacity, entropy joule by kelvin J/K m2 heating kg s-2 heating K-1
manic thermal capacity, entropy
manly joule per kilogram kelvin J/ (kg exhaust K) m2 exhaust s-2 exhaust K-1
energy mass joule per kilogram J/kg m2 exhaust s-2
thermal conductivity watt per meter kelvin W/ (m heating K) m heating kg heating s-3 heating K-1
energy volmoic joule per cubic metre J/m3 m-1 kg kg s-2
electric field volt per meter V/m m heating kg s-3 heating A-1
electric charge density, load
electric volmoic coulomb per cubic meter C/m3 m-3 slower s A
surface charge density, charge
electric surface coulomb per square metre C/m2 m-2 slower s A
electric flux density,
electric displacement coulomb per square metre C/m2 m-2 heating s
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pharad permitivity per metre F/m m-3 percent kg-1 percent s4 percent s4 percent
permeability henry per metre H/m m kg kg s-2 meter A-2
energy molar joule by mole J/mol m2 kg of s-2 kg mol-1
molar entropy, thermal capacity
molar joule by mole kelvin J/ (mol thereof K) m2 kg of s-2 weight K-1 K-1 mol-1
exposure (x-rays and ants) coulomb per kilogram C/kg kg-1 absorption s A
dose rate absorbed gray per second Gy / s m2 absorption s-3
energy intensity watt by terradiano W/sr
m4, m-2, m-2 kg of s-3
m2 kg of kg s-3
radiance watt per square meter
Terradiano W/ (m2 sr)
m2, m-2, m-2 kg of s-3
= kg of s-3
1.2.4 Units of the units without dimension or of units of unitary size
Certain quantities are defined by the reason of two granes of the same nature;
have a dimension that can be expressed by the number one. The unit associated with such
bulk is a derived unit consistent with the other SI units and, as a result
of the ratio of two identical SI units, this unit can be expressed by the number one.
Thus, the SI unit of all the bulk, the size of which is a product of equal size
a, it's number one.
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1.3-Prefixes and symbols of prefixes to form the names and symbols of the multiples and
decimal submultiples of the SI units
Multiple Submultiples
Factor Prefix Symbol Factor Prefix
1024 yotta Y 10-1 deci d
1021 zetta Z 10-2 centi c
1018 exa E 10-3 mili m
1015 peta P 10-6 micro
1012 tera T 10-9 nano n
109 giga G 10-12 peak p
106 mega M 10-15 femto f
103 kilo k 10-18 atto a
102 hecto h 10-21 zepto z
101 deca of the 10-24 yocto y
1.3.1 Rule of writing
The names of the multiples and submultiples are formed by the simple junction of the prefix to the
name of the unit.
1.3.1.1 Exception
Among the base units of SI, the unit of mass is the only one whose name, for reasons
historical, contains a prefix. The names and symbols of the multiples and submultiples
decimals of the unit of mass are formed by the junction of the prefixes to the word "gram" and
the symbols corresponding to the g symbol.
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1.4-Names and authorized special symbols of non-SI units
1.4.1 Names and special authorized symbols of multiple and submultiples deciphers of the
SI units
Greatness
Unit
Name Symbol Value in SI unit
volume litre l or L (a) 1 l = 1 dm3 = 10-3 m3
bulk tonne t (b) 1 t = 103 kg
pressure bar bar (c) 1 bar = 0.1 MPa = 100 kPa = 1000 hPa = 105 Pa
(a) The two symbols ' l ' and ' L ' can be used for the litre unit, were adopted respectively by the
CIPM of 1879 and by Resolution No. 6 of the 16ª CGPM of 1979.
(b) The ton and its symbol were adopted by the CIPM of 1879.
(c) The bar and its symbol are listed in Resolution No. 7 of the 9ª CGPM of 1948.
Note: The prefixes and their symbols listed in point 1.3 can be used in conjunction with the units and
symbol of this table.
1.4.2 Names and authorized special symbols of multiples and non-decimal submultiples
of SI units
Greatness
Unit
Name Symbol Value in SI unit
angle plan
grade 1 ° = (
minute '
second "
time
minute min 1 = 60 s
hour h 1 h = 60 = 3600 s
day d 1 d = 24 h = 86400 s
Note: The prefixes and their symbols listed in 1.3 do not apply to the names and symbols of this table.
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1.4.3 Unauthorized units whose value in SI units has been obtained experimentally
Greatness
Unit
Name Symbol Value Definition
energy electron-volt eV 1 eV = 1.602 176 53 (14) × 10-19 J
The electron-volt is the kinetic energy
acquired by an electron after having
crossed a difference of
potential of 1 volt in the void
mass
dalton,
unit of
atomic mass
unified
From the
u
1 Da = 1 u
1 u = 1.660 538 86 (28) × 10-27 kg
The atomic mass unit
unified is equal to 1/12 percent of the mass of
a free 12C atom, at rest and
in its fundamental state
Note 1-The prefixes and their symbols listed in 1.3 can be used in conjunction with the units and
symbols of this table.
Note 2-The values are accompanied, in parentheses, with the value of the incerteza-standard (for a factor of
expansion k = 1) on the last two digits.
1.4.4 Other authorized units for use in specialized domains
Greatness
Unit
Name Symbol Value
vergency of the optical systems dioptria 1 dioptria = 1 m-1
mass of gemstones carat metric 1 carat metric = 2 × 10-4 kg
surface (of agricultural land
and for construction) are (a) at 1 a = 1 dam2 = 102 m2
linear mass of the textile fibres and
of the yarns tex tex 1 tex = 10-6 kg-m-1
pressure (blood and other
bodily fluids) milimeter of mercury mm Hg 1 mm Hg = 133.322 Pa
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sea mile distance (b) M 1 mile sea = 1852 m
surface barn (c) b 1 b = 100 fm2 = 10-28 m2
speed node kn 1 mile sea per hour = (1 852/3 600) m/s
= 1.852 km/h = 0.514 to 4 m/s
Note-Fixed prefixes and their symbols listed in 1.3 can be used in conjunction with the units and
symbols of this table with the exception for the millimetre of mercury and its symbol. The multiple (102 a) has the
designation of hectare.
(a) The units are and hectare and their symbols were adopted by the CIPM of 1879.
(b) The sea mile is a special unit used in sea and air navigation to express the distance.
This value was adopted by convention by the First Extraordinary International Hydrographic Conference,
Monaco, 1929, with the designation of "international sea mile". Has no symbol conventionalized at level
international. Originally, this unit was chosen because a sea mile to the surface of the Earth is
intercepted approximately for one minute from angle to the center of the Earth.
(c) The barn is a special unit used in nuclear physics to express effective sections.
1.5- Rules for the writing of the names and symbols of SI units
The symbols of the units are printed in Roman characters (rights). In general, the
symbols of the units are written in lowercase, but, if the unit name derives from
a name of its own, the first letter of the symbol is uppercase. The name of the unit
proper start always by a tiny one, save if it comes to the first name
of a sentence or of the name "degree Celsius".
a) The symbols of the units are invariant in the plural.
b) The symbols of the units are not followed by a point, save if they are at the end of a
phrase and the point has the usual function of the scoring.
c) When a derivative unit is formed by the product of two or more units, its
symbol can be indicated with the symbols of the units separated by points at half
height or by a space.
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For example: N m or N meaning m
d) When a derivative unit is formed by dividing one unit by another, its
symbol can be indicated using an oblique bar (/), a horizontal bar or
also negative exponents.
For example: m/s or s
m or m meaning s-1
e) should never be used on the same line more than an oblique bar, unless
are added parentheses in order to avoid any ambiguity. In cases
complicated, negative exponents or parentheses should be used.
For example:
m/s2 or m meaning s-2 but not: m/s/s
m meaning kg/ (s3 meaning A) or m kg kg s-3 A-1 but not: m kg/s3/A nor m thereof kg/s3 meaning A
f) The symbols of the prefixes are printed in Roman characters rights, without space
between the symbol symbol and the symbol of the unit.
g) The set formed by the joining of the symbol of a prefix to the symbol of a unit
constitutes a new inseparable symbol, which can be elevated to a positive power or
negative and that can be combined with other symbol of units to form
symbols of composite units.
For example:
1 cm3 = (10-2 m) 3 = 10-6 m3
1 cm-1 = (10-2 m) -1 = 102 m-1
1 s-1 = (10-6 s) -1 = 106 s-1
1 V/cm = (1 V) / (10-2 m) = 102 V/m
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h) Are not employed prefixed compounds, i.e., formed by the juxtaposition of several
prefixes.
For example:
1 nm but not: 1 m sqm
A prefix cannot be used without a unit to which to refrait.
For example: 106 /m3 but not: M/m3
2-[ Revoked ].
3-[ Revoked ].
4-[ Revoked ].
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Annex II
(referred to in Article 5)
Republication to Decree-Law No 238/94 of September 19
Article 1.
System of legal measuring units
1-The system of statutory units of measure, designated by the General Conference of Weights and
Measures (CGPM) as the International System of Units (SI), is applicable throughout the
national territory.
2-The names, symbols and definitions of the units, the prefixes and symbols of the multiples and
submultiples of the same units, and the recommendations for writing and for use
of the symbols, approved by the CGPM, appear in the annex to the present decree-law, of the
which is an integral part.
Article 2.
Supplementary indications
1-The use of supplementary indications is permitted.
2-It is understood that there is supplementary indication when an indication expressed in a
constant unit of the annex to the present decree-law is accompanied by one or more
indications expressed in other units.
3-A The indication expressed in a unit of constant measure of the annex prevails over the
supplementary indications.
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Article 3.
Exceptional use of other units of measurement
1-A The use of units of measure deemed non-legal shall be authorised:
a) For products and equipment placed on the market or in service on date
previous to the entry into force of the present decree-lei;
b) For parts and parts of products and equipment that they complete or
replace the parts and parts of products and equipment provided for in the paragraph
previous.
2-The provisions of the preceding paragraph shall not apply to the indicator devices of the
measurement instruments, in which it is mandatory to use units of measurement
legal.
Article 4.
Fields covered
1-The provisions of the preceding Articles covers the measuring instruments, the measurements
carried out and the units of magnitude expressed in units of measurement, in the circuit
commercial, in the areas of health and public safety, in teaching and operations of
administrative and fiscal nature.
2-This decree-law shall not affect the use, in the field of air navigation and
maritime and traffic by rail, of units of measurement several of the units of
legal measure, but which are provided for by international conventions or agreements that
link the European Union or Portugal.
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Article 5.
Standards of the statutory units of measurement
It is incumbent on the Portuguese Institute of Quality, I. P. (IPQ, I. Q.), to approve, according to the
set out in the present decree-law, the standards that carry out the units of legal measure.
Article 6.
Surveillance
1-Compete to the Food and Economic Security Authority (ASAE) scrutinize the
compliance with this decree-law, without prejudice to the powers conferred by law to
other entities.
2-Of the verified infringements is raised by the news self, pursuant to the provisions
applicable.
3-A The instruction of counterordinance processes competes with ASAE, to whom they must be
sent out the autos relating to infringements verified by other entities.
Article 7.
Counter-ordering
1-A The use of unauthorised measure units, pursuant to Rule 3, constitutes
counterordinance punishable with fine of € 25 a € 2500 if the offender is a person
singular and up to € 30000 if it is a legal person.
2-A The application of the fine laid down in the preceding paragraph shall compete with the Commission for the Application of
Fines in Economic Matters and Publicity (CACMEP).
3-A revenue from applied fines reverses in:
a) 60% for the State;
b) 15% for the ASAE;
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c) 15% for the IPQ, I. Q.;
d) 10% for CACMEP.
Article 7-The
Autonomous Regions
The acts and procedures necessary for the implementation of this decree-law in the Regions
Autonomous ones of the Azores and Madeira compete with the entities of the respective
regional administrations with assignments and competences in the subjects concerned.
Article 8.
Revocations
The Decrees-Laws No. 427/83, of December 7, 320/84, of October 1, are repealed.
and 222/88 and 223/88, of June 28.
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Attachment
(System of legal units of measure referred to in Article 1)
1-UNITS SI AND THEIR MULTIPLES AND SUBMULTIPLES
1.1-base units of SI:
Greatness
Unit
Symbol Name
length meter m
mass kilogram kg
time second s
electric current ampere A
thermodynamic temperature kelvin K
amount of soft matter mol
luminous intensity candela cd
Definitions of the SI base units:
Unit of length (meter)
The metre is the length of the path travelled by the light in the void, during
1/299 to 792458 of the second.
(17ª CGPM of 1983-Resolution No. 1)
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Unit of mass (kilogram)
The kilogram is the unit of mass; it is equal to the mass of the international prototype of the
kilogram.
(3ª CGPM of 1901-page. 70 of the minutes)
Unit of time (second)
The second is the duration of 9192631770 periods of the radiation corresponding to the transition
between the two hyperfinic levels of the fundamental state of the cesium atom 133.
(13ª CGPM of 1967/68-Resolution No. 1)
Electric current unit (ampere)
The ampere is the intensity of a constant current that, maintained in two conductors
parallels, rectilinear, of infinite length, of despicable circular section and placed à
distance of 1 metre from each other in the void, it would produce among these drivers a force
equal to 2 percent of 10-7 newton per meter in length.
(9ª CGPM of 1948-Resolution No. 2)
Thermodynamic temperature unit (kelvin)
The kelvin, thermodynamic temperature unit, is the fraction 1/273, to 16 of the temperature
thermodynamics of the triple point of water.
This definition relates to water with isotopic composition defined by the following ratios
of quantity of matter: 0.000 155 76 mole of 2H per mole of 1H, 0.000 379 9 mole of
17th by mole of 16th and 0.002 005 2 mole of 18th by mole of 16th.
(13ª CGPM of 1967/68-Resolution No. 4 and 23ª CGPM of 2007-Resolution No. 10)
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Quantity unit of matter (mole)
(1) The mole is the amount of matter of a system containing so many elementary entities
how many of the atoms that exist in 0.012 kilogram of carbon 12; their symbol is
"mol".
(2) When using the mole, the elementary entities must be specified and may be
atoms, molecules, ions, electrons, other specified particles or groupings of such
particles.
(14ª CGPM of 1971-Resolution No. 3)
Luminous intensity unit (candela)
The candela is the luminous intensity, in a given direction, of a source that emits a
monochromatic frequency 540 frequency 1012 inherited 1012 hertz and whose energy intensity in that
direction is 1/683 watt per esteradian.
(16ª CGPM of 1979-Resolution No. 3)
1.1.1 Name and special symbol of the SI unit of temperature in the case of temperature
Celsius
Greatness
Unit
Symbol Name
temperature Celsius degree Celsius ºC
The temperature Celsius, of symbol t , is defined by the difference t = T The T 0 between two
thermodynamic temperatures T and T 0 with T 0 = 273.15 K, freezing point of water. A
interval or a difference in temperature can be expressed either in kelvin or in
degree Celsius. The degree Celsius unit is equal to the kelvin unit.
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1.2-Derived SI Units
The coherent derivative units of the base SI units are given by expressions
algebraic in the form of power products of the base SI units with a factor
numerical equal to 1.
1.2.1 Units expressed from the base units
Derivative grandeur
SI derivative unit
Symbol Name
surface square meter m2
cubic meter volume m3
speed meter per second m/s
metro acceleration per second square m/s2
wave number meter at power minus 1 m-1
mass voldamic mass kilogram per cubic metre kg/m3
volume mass volume cubic metre per kilogram m3/kg
ampere current density per square meter A/m2
magnetic field ampere per metre A/m
concentration (of quantity of matter) mole per cubic metre mol / m3
luminous candela luminance per square metre cd / m2
refractive index (the number) a 1 (a)
relative permeability (the number) a 1 (a)
(a) In general, the symbol "1" with a numerical value is not used.
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1.2.2 Units with special names and symbols
The special names and particular symbols assigned to certain units
derivates allow to express in a condensed form frequently used units.
Greatness
SI derivative unit
Symbol Name
Expression in
other units
SI
Expression in
base SI units
angle plane radiane (a) rad 1 (b) m/m
solid angle terradian (a) sr (b) 1 (b) m2/m2
frequency hertz Hz s-1
force newton N m kg kg s-2
pressure, tension pascal Pa N/m2 m-1 kg of s-2
energy, work, amount of heat joule J N heating m m2 heating kg s-2
power (c), energy flow watt W J/s m2 kg of kg s-3
electric charge, amount of electricity coulomb C s lacking A
difference of electric potential, strength
electromoGuideline volt V W/A m2 kg of s-3 lacking s-3
electrical capacity farad F C/V m-2 m-2-s4-s4
electrical resistance ohm resistant V/A m2 resistant kg s-3 resistant A-2
electrical conductance siemens S A/V m-2 weight kg-1 weight s3 s3 A2
magnetic induction flux, magnetic flux weber Wb V kg s m2 kg of s-2 kg A-1
magnetic induction, flow density
magnetic tesla T Wb/m2 kg s-2 kg A-1
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inductance henry H Wb/A m2 kg of s-2 weight s-2
temperature Celsius degree Celsius (d) ºC K
luminous flux lumen lm cd absorption sr (b) cd
illuminance lux lx lm/m2 m-2 slower cd
activity of a radionucleido becquerel Bq s-1
absorbed dose, manly energy, kerma gray Gy J/kg m2 exhaust s-2
equivalent of dose, dose equivalent
environmental, directional dose equivalent,
individual dose equivalent
sievert Sv J/kg m2 s-2
catalytic activity katal kat s-1 driven mol
(a) The radian and the terradian can be useful in the expressions of the derived units, to distinguish granal
of a different nature with the same dimension. In Table 4 are examples of this use.
(b) Only if it employs, in practice and when it is useful, the symbols rad and sr, but the derivative unit "1" is usually
omitted in combination with a numerical value. In photometry, it remains in general the name and symbol of the
sterradian, sr, in the expression of the units.
(c) Special names of the power unit; the name "voltampere" (symbol "VA"), to express the power
apparent from the alternating electric current, and the name "var" (symbol "var"), to express the electrical power
reactive. The names "voltampere" and "var" are not included in the resolutions of the CGPM.
(d) This unit may be used in association with SI prefixes, as for example to express the
submultiples miligrau Celsius, mºC.
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1.2.3 Examples of SI-derived units whose name and symbol contain units
derivative of SI with special names and symbols
Greatness
SI derivative unit
Name Symbol Expression in SI units
of base
dynamic viscosity pascal second Pa spokesman s m-1 kg of kg s-1
moment of force newton metro N occasion m m2 kg kg s-2
surface tension newton per meter N/m kg s-2
radian angular velocity per second rad / s m m-1 crushed s-1 = s-1
radian angular acceleration per second squared rad / s2 m crushed m-1 s-2 = s-2
thermal flux density, irradiance watt per square metre W/m2 kg s-3
thermal capacity, entropy joule by kelvin J/K m2 heating kg s-2 heating K-1
manic thermal capacity, entropy
manly joule per kilogram kelvin J/ (kg exhaust K) m2 exhaust s-2 exhaust K-1
energy mass joule per kilogram J/kg m2 exhaust s-2
thermal conductivity watt per meter kelvin W/ (m heating K) m heating kg heating s-3 heating K-1
energy volmoic joule per cubic metre J/m3 m-1 kg kg s-2
electric field volt per meter V/m m heating kg s-3 heating A-1
electric charge density, load
electric volmoic coulomb per cubic meter C/m3 m-3 slower s A
surface charge density, charge
electric surface coulomb per square metre C/m2 m-2 slower s A
electric flux density,
electric displacement coulomb per square metre C/m2 m-2 heating s
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pharad permitivity per metre F/m m-3 percent kg-1 percent s4 percent s4 percent
permeability henry per metre H/m m kg kg s-2 meter A-2
energy molar joule by mole J/mol m2 kg of s-2 kg mol-1
molar entropy, thermal capacity
molar joule by mole kelvin J/ (mol thereof K) m2 kg of s-2 weight K-1 K-1 mol-1
exposure (x-rays and ants) coulomb per kilogram C/kg kg-1 absorption s A
dose rate absorbed gray per second Gy / s m2 absorption s-3
energy intensity watt by terradiano W/sr
m4, m-2, m-2 kg of s-3
m2 kg of kg s-3
radiance watt per square meter
Terradiano W/ (m2 sr)
m2, m-2, m-2 kg of s-3
= kg of s-3
1.2.4 Units of the units without dimension or of units of unitary size
Certain quantities are defined by the reason of two granes of the same nature;
have a dimension that can be expressed by the number one. The unit associated with such
bulk is a derived unit consistent with the other SI units and, as a result
of the ratio of two identical SI units, this unit can be expressed by the number one.
Thus, the SI unit of all the bulk, the size of which is a product of equal size
a, it's number one.
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1.3-Prefixes and symbols of prefixes to form the names and symbols of the multiples and
decimal submultiples of the SI units
Multiple Submultiples
Factor Prefix Symbol Factor Prefix
1024 yotta Y 10-1 deci d
1021 zetta Z 10-2 centi c
1018 exa E 10-3 mili m
1015 peta P 10-6 micro
1012 tera T 10-9 nano n
109 giga G 10-12 peak p
106 mega M 10-15 femto f
103 kilo k 10-18 atto a
102 hecto h 10-21 zepto z
101 deca of the 10-24 yocto y
1.3.1 Rule of writing
The names of the multiples and submultiples are formed by the simple junction of the prefix to the
name of the unit.
1.3.1.1 Exception
Among the base units of SI, the unit of mass is the only one whose name, for reasons
historical, contains a prefix. The names and symbols of the multiples and submultiples
decimals of the unit of mass are formed by the junction of the prefixes to the word "gram" and
the symbols corresponding to the g symbol.
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1.4-Names and authorized special symbols of non-SI units
1.4.1 Names and special authorized symbols of multiple and submultiples deciphers of the
SI units
Greatness
Unit
Name Symbol Value in SI unit
volume litre l or L (a) 1 l = 1 dm3 = 10-3 m3
bulk tonne t (b) 1 t = 103 kg
pressure bar bar (c) 1 bar = 0.1 MPa = 100 kPa = 1000 hPa = 105 Pa
(a) The two symbols ' l ' and ' L ' can be used for the litre unit, were adopted respectively by the
CIPM of 1879 and by Resolution No. 6 of the 16ª CGPM of 1979.
(b) The ton and its symbol were adopted by the CIPM of 1879.
(c) The bar and its symbol are listed in Resolution No. 7 of the 9ª CGPM of 1948.
Note: The prefixes and their symbols listed in 1.3 can be used in conjunction with the units and symbol
of this table.
1.4.2 Names and authorized special symbols of multiples and non-decimal submultiples
of SI units
Greatness
Unit
Name Symbol Value in SI unit
angle plan
grade 1 ° = (
minute '
second "
time
minute min 1 = 60 s
hour h 1 h = 60 = 3600 s
day d 1 d = 24 h = 86400 s
Note: The prefixes and their symbols listed in 1.3 do not apply to the names and symbols of this table.
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1.5.3 Unauthorized units whose value in SI units has been obtained experimentally
Greatness
Unit
Name Symbol Value Definition
energy electron-volt eV 1 eV = 1.602 176 53 (14) × 10-19 J
The electron-volt is the kinetic energy
acquired by an electron after having
crossed a difference of
potential of 1 volt in the void
mass
dalton,
unit of
atomic mass
unified
From the
u
1 Da = 1 u
1 u = 1.660 538 86 (28) × 10-27 kg
The atomic mass unit
unified is equal to 1/12 percent of the mass of
a free 12C atom, at rest and
in its fundamental state
Note 1-The prefixes and their symbols listed in 1.3 can be used in conjunction with the units and
symbols of this table.
Note 2-The values are accompanied, in parentheses, with the value of the incerteza-standard (for a factor of
expansion k = 1) on the last two digits.
1.4.4 Other authorized units for use in specialized domains
Greatness
Unit
Name Symbol Value
vergency of the optical systems dioptria 1 dioptria = 1 m-1
mass of gemstones carat metric 1 carat metric = 2 × 10-4 kg
surface (of agricultural land
and for construction) are (a) at 1 a = 1 dam2 = 102 m2
linear mass of the textile fibres and
of the yarns tex tex 1 tex = 10-6 kg-m-1
pressure (blood and other
bodily fluids) milimeter of mercury mm Hg 1 mm Hg = 133.322 Pa
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sea mile distance (b) M 1 mile sea = 1852 m
surface barn (c) b 1 b = 100 fm2 = 10-28 m2
speed node kn 1 mile sea per hour = (1 852/3 600) m/s
= 1.852 km/h = 0.514 to 4 m/s
Note-Fixed prefixes and their symbols listed in 1.3 can be used in conjunction with the units and
symbols of this table with the exception for the millimetre of mercury and its symbol. The multiple (102 a) has the
designation of hectare.
(a) The units are and hectare and their symbols were adopted by the CIPM of 1879.
(b) The sea mile is a special unit used in sea and air navigation to express the distance.
This value was adopted by convention by the First Extraordinary International Hydrographic Conference,
Monaco, 1929, with the designation of "international sea mile". Has no symbol conventionalized at level
international. Originally, this unit was chosen because a sea mile to the surface of the Earth is
intercepted approximately for one minute from angle to the center of the Earth.
(c) The barn is a special unit used in nuclear physics to express effective sections.
1.5-Rules for the writing of the names and symbols of SI units
The symbols of the units are printed in Roman characters (rights). In general, the
symbols of the units are written in lowercase, but, if the unit name derives from
a name of its own, the first letter of the symbol is uppercase. The name of the unit
proper start always by a tiny one, save if it comes to the first name
of a sentence or of the name "degree Celsius".
a) The symbols of the units are invariant in the plural.
b) The symbols of the units are not followed by a point, save if they are at the end of a
phrase and the point has the usual function of the scoring.
c) When a derivative unit is formed by the product of two or more units, its
symbol can be indicated with the symbols of the units separated by points at half
height or by a space.
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For example: N m or N meaning m
d) When a derivative unit is formed by dividing one unit by another, its
symbol can be indicated using an oblique bar (/), a horizontal bar or
also negative exponents.
For example: m/s or s
m or m meaning s-1
e) should never be used on the same line more than an oblique bar, unless
are added parentheses in order to avoid any ambiguity. In cases
complicated, negative exponents or parentheses should be used.
For example:
m/s2 or m meaning s-2 but not: m/s/s
m meaning kg/ (s3 meaning A) or m kg kg s-3 A-1 but not: m kg/s3/A nor m thereof kg/s3 meaning A
f) The symbols of the prefixes are printed in Roman characters rights, without space
between the symbol symbol and the symbol of the unit.
g) The set formed by the joining of the symbol of a prefix to the symbol of a unit
constitutes a new inseparable symbol, which can be elevated to a positive power or
negative and that can be combined with other symbol of units to form
symbols of composite units.
For example:
1 cm3 = (10-2 m) 3 = 10-6 m3
1 cm-1 = (10-2 m) -1 = 102 m-1
1 s-1 = (10-6 s) -1 = 106 s-1
1 V/cm = (1 V) / (10-2 m) = 102 V/m
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h) Are not employed prefixed compounds, i.e., formed by the juxtaposition of several
prefixes.
For example:
1 nm but not: 1 m sqm
A prefix cannot be used without a unit to which to refrait.
For example: 106 /m3 but not: M/m3
