S.I. No. 235/1983 - European Communities ((Units of Measurement) Regulations, 1983.

S.I. No. 235 of 1983.

EUROPEAN COMMUNITIES ((UNITS OF MEASUREMENT) REGULATIONS, 1983.

I, FRANK CLUSKEY, Minister for Trade, Commerce and Tourism, in exercise of the powers conferred on me by section 3 of the European Communities Act, 1972 (No. 27 of 1972), hereby make the following Regulations:

1 Citation and Commencement.

1. (1) These Regulations may be cited as the European Communities (Units of Measurement) Regulations, 1983.

(2) These Regulations will come into effect on the 1st day of November, 1983.

2 Revocation.

2. The European Communities (Units of Measurement) Regulations, 1976, are hereby revoked.

3 Council Directive on Units of Measurement.

3. In these Regulations "the Council Directive on units of measurement" means Council Directive No. 80/181/EEC of 20th December, 1979¹ on the approximation of the laws of the Member States of the European Communities relating to units of measurement and on the repeal of Council Directive No. 71/354/EEC of 18th October, 1971².

¹O.J. No. L39, 15/2/80, p.40.

²O.J. No. L243, 29/10/7l, p. 29.

4 Legal units of measurement.

4. (1) The units of measurement named in Chapter I (set out in Schedule 1 of these Regulations) of the Annex to the Council Directive on units of measurement are authorised for use in the State and all units of measurement in the metric system shall be determined in accordance with that Chapter.

(2) The units of measurement named in Chapter II (set out in Schedule 2 of these Regulations) of the Annex to the Council Directive on units of measurement are authorised for use in the State until 31st December, 1985.

5 National metric standards.

5. The national standards for the metre (the unit of measurement of length) and the kilogram (the unit of measurement of mass) are described in Schedule 3 of these Regulations and deposited in the Institute for Industrial Research and Standards. They shall be the standards by reference to which all other standards of those units and of any other unit of measurement derived wholly or partly from any of those units shall be maintained.

6 Unauthorised units of measurement.

6. With effect from the commencement of these Regulations and subject to Regulations 7 (2), 10 and 11 (2), the units of measurement named in Schedule 4 of these Regulations shall cease to be authorised for use in the State.

7 Contravention of Regulations.

7. (1) A person who uses any unit of measurement in contravention of Regulation 6 as applied by Regulation 11 shall be guilty of an offence and shall be liable on summary conviction to a fine not exceeding £800.

(2) Except in the case of a retail transaction or a transaction relating to packaged goods where an unauthorised unit of measurement is used without its metric equivalent, it shall not be unlawful to use in any transaction, by agreement between the parties thereto, any unit of measurement which was hitherto customarily used in trade in like transactions.

8 Effect on contracts.

8. Section 19 of the Weights and Measures Act, 1878, shall cease to have effect insofar as it makes void any transaction not made according to a weight or measure to which that section refers.

9 Existing Contracts.

9. Where a contract entered into before the commencement of these Regulations falls to be performed or to be performed partly on or after that date and the contract refers to a unit of measurement named in Schedule 4 of these Regulations, that reference shall on and after the commencement of these Regulations be deemed to be a reference to the value set out in the appropriate column of that Schedule in relation to that unit; and accordingly any calculation that has under the contract to be made by reference to that unit shall instead be made by reference to that value.

10 Use of unauthorised unit.

10. (1) ( a ) A unit which ceases to be authorised may continue to be used as a supplementary indication accompanying an indication of quantity expressed in an authorised unit.

( b ) The indication expressed in an authorised unit shall predominate and a supplementary indication shall be expressed in characters no larger than those of the corresponding indication in an authorised unit.

( c ) In the case of conflict between an indication of quantity expressed in an authorised unit and a supplementary indication the latter shall be disregarded.

(2) A unit of measurement which ceases to be authorised may continue to be used for—

( a ) products and equipment already on the market or in service on the commencement of these Regulations,

( b ) components and parts of products and of equipment necessary to supplement or replace components or parts of the said products and equipment.

11 Application.

11. (1) These Regulations apply to measuring instruments used, measurements made and dimensions or quantities expressed in units, whether for trade or for any economic, public health, public safety or administrative purpose in the State.

(2) These Regulations shall not affect the use in the field of air and sea transport and rail traffic of units, other than those authorised by these Regulations, which have been laid down in international conventions or agreements binding the Community or the Member States.

12 Modification of legislation.

12. (1) The provisions of the Weights and Measures Acts, 1878 to 1961, and any other relevant enactment shall be construed together with and subject to these Regulations and, in the event of any inconsistency between these Regulations and any such provision, that provision shall, to the extent of the inconsistency, cease to have the force of law.

(2) ( a ) Every reference in any such enactment to a unit of measurement which by virtue of these Regulations ceases to be authorised shall be construed as a reference to the appropriate unit authorised by these Regulations or otherwise by law.

( b ) Every reference in any such enactment to a measurement in a unit of measurement which by virtue of these Regulations ceases to be authorised shall be construed as a reference to the equivalent measurement in a unit authorised by these Regulations or otherwise by law.

SCHEDULE 1.

LEGAL UNITS OF MEASUREMENT REFERRED TO IN REGULATION 4 (1)

1. SI UNITS AND THEIR DECIMAL MULTIPLES AND SUBMULTIPLES

1.1 SI base units

Quantity	Unit
Name	Symbol
Length	metre	m
Mass	kilogram	kg
Time	second	s
Electric current	ampere	A
Thermodynamic temperature	kelvin	K
Amount of substance	mole	mol
Luminous intensity	candela	cd

Definitions of SI base units:

Unit of length

The metre is the length equal to 1 650 763.73 wavelengths in vacuum of the radiation corresponding to the transition between the levels 2p₁₀ and 5d₅ of the krypton-86 atom.

Unit of mass

The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram.

Unit of time

The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom.

Unit of electric current

The ampere is that constant current, which if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one metre apart in vacuum, would produce between those conductors a force equal to 2 x 10^-7 newton per metre of length.

Unit of thermodynamic temperature

The kelvin, unit of thermodynamic temperature, is the fraction ½73.16 of the thermodynamic temperature of the triple point of water.

Unit of amount of substance

(1) The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12.

(2) When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.

Unit of luminous intensity

The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency of 540 x 10¹² hertz and that has a radiant intensity in that direction of (1/683) watt per steradian.

1.1.1 Special name and symbol of the SI unit of temperature for expressing Celsius temperature

Quantity	Unit
Name	Symbol
Celsius temperature	degree Celsius	°C

Celsius temperature t is defined as the difference t = T-T₀ between the two thermodynamic temperatures T and T₀ where T₀ = 273.15 kelvins. An interval of or difference in temperature may be expressed either in kelvins or in degrees Celsius. The unit 'degree Celsius' is equal to the unit 'kelvin'.

1.2 Other SI units

1.2.1. SI supplementary units

Quantity	Unit
	Name	Symbol
Plane angle	radian	rad
Solid angle	steradian	sr

Definitions of SI supplementary units:

Unit of plane angle

The radian is the plane angle between two radii of a circle which cut off on the circumference an arc equal in length to the radius.

Unit of solid angle

The steradian is the solid angle which, having its vertex at the centre of a sphere, cuts off an area on the surface of the sphere equal to that of a square with sides of length equal to the radius of the sphere.

1.2.2. SI derived units

Units derived coherently from SI base units and SI supplementary units are given as algebraic expressions in the form of products of powers of the SI base units and/or SI supplementary units with a numerical factor equal to 1.

1.2.3. SI derived units having names and symbols

Quantity	Unit		Expression
Name	Symbol	In other SI units	In terms of SI base or supplementary units
Frequency	hertz	Hz		s^-1
Force	newton	N		m·kg·s^-2
Pressure, stress	pascal	Pa	N·m^-2	m^-1·kg·s^-2
Energy, work; quantity of heat	joule	J	N·m	m²·kg·s^-2

Power ,⁽¹⁾ radiant flux	watt	W	J·s^-1	m²·kg·s^-3
Quantity of electricity, electric charge	coulomb	C		s·A
Electric potential, potential difference, electromotive force	volt	V	W·A^-1	m²·kg·s^-3·A^-1
Electric resistance	ohm	Ω	V·A^-1	m².kg·s^-3·A^-2
Conductance	siemens	S	A·V^-1	m^-2·kg^-1·s³·A²
Capacitance	farad	F	C·V^-1	m^-2·kg^-1·s⁴·A²
Magnetic flux	weber	Wb	V·s	m²·kg·s^-2·A^-1
Magnetic flux density	tesla	T	Wb·m^-2	kg·s^-2·A^-1
Inductance	henry	H	Wb·A^-1	m²·kg·s^-2·A^-2
Luminous flux	lumen	lm		cd·sr
Illuminance	lux	lx	lm·m^-2	m^-2·cd·sr
Activity (of a radionuclide)	becquerel	Bq		s^-1
Absorbed dose, specific energy inparted, kerma, absorbed dose index	gray	Gy	J·kg^-1	m²·s^-2
Dose equivalent	sievert	Sv	J·kg^-1	m^2·s^-2

⁽¹⁾Special names for the unit of power: the name volt-ampere (symbol 'VA') when it is used to express the apparent power of alternating electric current, and var (symbol 'var') when it is used to express reactive electric power.

_____________________________________________________________________

Units derived from SI base units or supplementary units may be expressed in terms of the units named in Schedule 1.

In particular, SI derived units may be expressed by the special names and symbols given in the above table; for example, the SI unit of dynamic viscosity may be expressed as m^-1.kg.s^-1 or N^.s^.m^-2 or Pa^.s

1.3. Prefixes and their symbols used to designate certain decimal multiples and submultiples

Factor	Prefix	Symbol	Factor	Prefix	Symbol
10¹⁸	exa	E	10^-1	deci	d
10¹⁵	peta	P	10^-2	centi	c
10¹²	tera	T	10^-3	milli	m
10⁹	giga	G	10^-6	micro	μ
10⁶	mega	M	10^-9	nano	n
10³	kilo	k	10^-12	pico	p
10²	hecto	h	10^-15	femto	f
10¹	deca	da	10^-18	atto	a

The names and symbols of the decimal multiples and submultiples of the unit of mass are formed by attaching prefixes to the word 'gram' and their symbols to the symbol '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 these parts.

Compound prefixes, that is to say prefixes formed by the juxtaposition of several of the above prefixes, may not be used.

1.4. Special authorized names and symbols of decimal multiples and submultiples of SI units

Quantity	Unit
Name	Symbol	Value
Volume	litre	l or L(¹)	1 l = 1 dm³ = 10^-3m³
Mass	tonne	t	1 t = 1 Mg = 10³ kg
Pressure, stress	bar	bar	1 bar = 10⁵ Pa
⁽¹⁾ The two symbols 'l' and 'L' may be used for the litre unit.

Note: The prefixes and their symbols listed in 1.3 may be used in conjunction with the units and symbols contained in Table 1.4.

2. UNITS WHICH ARE DEFINED ON THE BASIS OF SI UNITS BUT ARE NOT DECIMAL MULTIPLES OR SUBMULTIPLES THEREOF

Quantity	Unit
Name	Symbol	Value
Plane angle	revolution (a)		1 revolution= 2 π rad
	grade or gon	gon
	degree	°
	minute of angle	'
	second of angle	"
Time	minute hour day	min h d	1 min = 60 s 1 h = 3 600 s 1 d = 86 400 s

(a) No international symbol exists.

Note: The prefixes listed in 1.3 may only be used in conjunction with the names 'grade' or 'gon' and the symbol 'gon'

3. UNITS DEFINED INDEPENDENTLY OF THE SEVEN SI BASE UNITS

The unified atomic mass unit is one-twelfth of the mass of an atom of the nuclide ¹²C.

The electronvolt is the kinetic energy acquired by an electron passing in a vacuum from one point to another whose potential is one volt higher.

Quantity	Unit
Name	Symbol	Value
Mass	unified atomic mass unit	u	1u ≈ 1.660 565 × 10^-27 kg
Energy	electronvolt	eV	1eV ≈ 1.602 189 × 10^-19 J

The value of these units, expressed in SI units, is not known exactly.

The above values are taken from CODATA Bulletin No 11 of December 1973 of the International Council of Scientific Unions.

Note: The prefixes and their symbols listed in 1.3 may be used in conjunction with these two units and with their symbols.

4. UNITS AND NAMES OF UNITS PERMITTED IN SPECIALIZED FIELDS ONLY

Quantity	Unit
	Name	Symbol	Value
Vergency of optical systems	dioptre		1 dioptre = 1 m^-1
Mass of precious stones	metric carat		1 metric carat = 2 × 10^-4kg
Area of farmland and building land	are	a	1 a = 10²m²
Mass per unit length of textile yarns and threads	tex	tex	1 tex = 10^-6kg.m^-1

Note: The prefixes listed in 1.3 may be used in conjunction with the above units. The multiple 10a is, however, called a hectare'.

5. COMPOUND UNITS

Combinations of the units named in Schedule 1 form compound units.

SCHEDULE 2.

LEGAL UNITS OF MEASUREMENT REFERRED TO IN REGULATION 4 (2).

QUANTITIES, NAMES OF UNITS, SYMBOLS AND VALUES

Quantity	Unit
	Name	Symbol	Value
Blood pressure	millimetre of mercury	mm Hg	1 mm Hg = 133.322 Pa
Plane angle		g ⁽¹⁾
Activity (of a radionuclide)	curie	Ci	1 Ci = 3·7 × 10¹⁰ Bq
Absorbed dose	rad	rad ⁽²⁾	1 rad = 10^-2Gy
Dose equivalent	rem	rem	1 rem = 10^-2Sv
Exposure (X and y rays	röntgen	R	1 R = 2.58.10^-4 C.kg^-1
Dynamic	poise	P	1 P = 10^-1Pa·s
viscosity
Kinematic	stokes	St	1 St = 10^-4m ·s^-1
viscosity
⁽¹⁾Symbol for 'grade'.
⁽²⁾When there is risk of confusion with the symbol for radian, rd may be used as symbol for rad.

Note: The prefixes and their symbols listed in 1.3 of SCHEDULE 1 may be used in conjunction with the units and symbols contained in this section, with the exception of millimetre of mercury and its symbol and the symbol 'g'.

Until the date indicated in Regulation 4 (2), the units named in Schedule 2 may be combined with each other or with those in Schedule 1 to form compound units.

SCHEDULE 3.

NATIONAL METRIC STANDARDS

Part 1

Description of national standard of the metre

The Irish copy of the international metre being a bar about 1030 millimetres long, of simple H section, 24 millimetres wide by 24 millimetres high, made of 58% nickel steel having the upper face of web in neutral plane and a polished scale engraved thereon, bearing the inscription

An Méadar Naísiunta, Eire 1969

The metre bar has also the following markings on the face:

( a ) NI 58% No. 15481 20°C

( b ) SIP Geneve Made in Switzerland

( c ) X NI 58% at its left extremity

( d ) 5036 at its right extremity

Part 2

Description of national standard of the kilogram

The Irish copy of the international prototype of the kilogram being a mass of stainless steel "Immaculate V" (25% chrome, 20% nickel) in the form of a cylinder of revolution, of diameter approximately equal to its height, and has rounded edges.

It is constructed of a single polished piece, without an interior cavity or attached pieces; on the upper face is placed the following identification mark:

1Kg

SCHEDULE 4

UNITS OF MEASUREMENT WHICH CEASE TO BE AUTHORISED

1. IMPERIAL UNITS

Quantities, Names of Units, Symbols and Approximate Values:

Quantity	Unit
	Name	Symbol	Approximate Value
Length	hand		1 hand = 0.1016 m
	chain		1 chain = 20.12 m
	furlong		1 furlong = 201.2 m
	nautical mile (UK)		1 nautical mile (UK) = 1853m
Area	square inch	sq. in.	1 sq. in. = 6.452 × 10^-4 m
	rood		1 rood = 1012 m
	square mile	sq. mile	1 sq. mile = 2.59 × 10⁶m²
Volume	cubic inch	cu. in.	1 cu. in. = 16.39 × 10^-6m³
	cubic foot	cu. ft.	1 cu. ft. = 0·0283 m³
	cubic yard	cu. yd.	1 cu. yd. = 0.7646 m³
	bushel (1)	bu.	1 bu. = 36.37 × 10^-3m³
	cran		1 cran = 170.5 × 10^-3m³
Mass	grain	gr.	1 gr. = 0.0648 × 10^-3kg
	dram	dr.	1 dr. = 1.772 × 10^-3kg
	stone	st.	1st. = 6.35 kg
	quarter	qr.	1 qr. = 12.70 kg
	cental	ctl.	1 ctl. = 45.36 kg
	hundredweight	cwt.	1 cwt. = 50.80 kg
	ton		1 ton = 1016 kg
Pressure	inch of water	in. H₂O	1 in. H₂O = 249.089 Pa
Force	pound force	1 bf	1 lbf = 4.448 N
	ton force	tonf	1 tonf = 9.964 × 10³ N
Illuminance	foot candle	ft. candle	1 ft. candle = 10.76 1x
Speed	knot (UK)		1 knot (UK) = 0.51477 m.s.^-1
Energy	British Thermal	Btu	1 Btu = 1055.06 J
	Unit
	foot pound force	ft. lbf	1 ft. lbf = 1.356 J
Power	horsepower (2)	hp.	1 hp. = 745.7 W.
	degree
Temperature	Fahrenheit	°F	1° F = (⁵/₉) K

(1) This does not affect the unit of measurement of mass (pound per bushel) and Regulation 7 of the European Communities (Standard Mass per Storage Volume of Grain) Regulations, 1976 ( S.I. No. 111 of 1976 ), continues to have effect.

(2) This does not apply to the unit employed for the purposes of excise duty on mechanically propelled vehicles used on public roads.

2. CGS UNITS

Quantities, Names of Units, Symbols and Values.

Quantity	Unit
Name	Symbol	Value
Force	dyne	dyn	1 dyn=10^-5N
Energy	erg	erg	l erg=10^-7J
Acceleration of free fall	gal	Gal	1 Gal= 10^-2 M·S^-2

3. OTHER UNITS

Quantities, names of units, symbols and values.

Quantity	Unit
Name	Symbol	Value
Wavelength, atomic distances	angstrom	A	1 A = 10^-10m
Effective cross -sectional area	barn	b	1 b = 10^-28 m²
Mass	quintal (a)		1 quintal = 10kg
Pressure	standard atmosphere	atm	1 atm = 101 325 Pa
Volume (forestry and timber trade)	stere	st	1 st = 1 m³

^(a) No international symbol exists.

4. SPECIAL UNITS

Quantities, names of units, symbols and values.

Quantity	Unit
	Name	Symbol	Value
Volume	Festmeter	Fm	1 Fm = 1 m³
(forestry and timber industry)	Raummeter	Rm	1 Rm = 1 m³
Force	kilogram force	kgf	1 kgf = 9.806 65 N
	kilopond	kp	l kp = 9.806 65 N
Pressure	torr	torr
	technical atmosphere	at	1 at = 98 066.5 Pa
	meter of water (conventionally: 1 m H₂O)	mH₂O	1 mH₂O = 9 806.65 Pa
	millimetre	mmHg	1 mmHg=133.322 Pa
	of mercury (1) (conventionally: 1 mm Hg)
Power	Pferdstarke	PS	1 Ps = 735.498 75W
	paardekracht	pk	1 pk = 735.498 75 W
	cheval vapeur	CV	1 CV = 735.498 75 W
	cavollo vapore	cv	1 cv = 735.498 75 W
Quantity of heat	calorie 15°C	cal ₁₅	1 cal ₁₅ = 4.185 5 J
	thermie	th	1 th = 4.185 5 × 10⁶J
	frigorie	fg	1 fg = 4.185 5 × 10³J
	calorie IT	cal_IT	cal_rr = 4.186 8J
	thermo-chemical	cal_th _ch	1 cal_th,_ch = 4.184J
	calorie
Luminance	stilb	sb	1 sb = 10⁴ cd.m^-2
Temperature	degree kelvin	°K	1°K=1K

⁽¹⁾Except where this unit is used for measuring blood pressure (see Schedule 2).

GIVEN under my Official Seal, this 28th day of July, 1983.

FRANK CLUSKEY,

Minister for Trade, Commerce

and Tourism.

EXPLANATORY NOTE.

These Regulations are made to give effect to Council Directive 80/181/EEC on the approximation of the laws of Member States relating to units of measurement. The Regulations provide for the withdrawal of certain imperial and other non-SI units of measurement on enactment, and of further units at the end of 1985. They also include a list of the SI (metric) units of measurement which are authorised for use in Ireland.