Advanced Search

International System Of Units (Si) Act

Subscribe to a Global-Regulation Premium Membership Today!

Key Benefits:

Subscribe Now for only USD$40 per month.
Revised Laws of Mauritius

I19 – 1 [Issue 1]

INTERNATIONAL SYSTEM OF UNITS (SI) ACT Act 6 of 1984 – 1 July 1984

ARRANGEMENT OF SECTIONS

SECTION 1. Short title 2. Interpretation 3. Units to be used 4. Multiples and sub-multiples 5. Symbols and prefixes 6. Regulations 7. Offences 8. — 9. Application of Act

10. The State 11. — FIRST SCHEDULE SECOND SCHEDULE THIRD SCHEDULE FOURTH SCHEDULE FIFTH SCHEDULE SIXTH SCHEDULE



INTERNATIONAL SYSTEM OF UNITS (SI) ACT

1. Short title

This Act may be cited as the International System of Units (SI) Act.

2. Interpretation

In this Act—

“Minister” means the Minister to whom responsibility for the subject of industry is assigned;

“quantity” means any physical characteristic which may be measured;

“SI unit” means a unit of the International System of Units approved by the General Conference on Weights and Measures (CGPM) established under the Metre Convention of 1875;

“vessel” has the same meaning as in the Ports Act.

3. Units to be used

(1) Subject to subsection (4), the measurement of any quantity shall be expressed in terms of SI units.

(2) The SI units shall consist of—

(a) base units;

(b) supplementary units; and

(c) derived units.

International System of Units (SI) Act

[Issue 1] I19 – 2

(3) For the purposes of subsection (2)—

(a) base units—

(i) are units specified in the second column;

(ii) shall be used in respect of the corresponding quantity specified in the first column,

of the First Schedule;

(b) supplementary units—

(i) are units specified in the second column;

(ii) shall be used in respect of the corresponding quantity specified in the first column,

of the Second Schedule;

(c) derived units—

(i) are units which are derived from base units or supplemen- tary units or both;

(ii) (A) include the units specified in the second column;

(B) shall be used in respect of the corresponding quantity specified in the first column,

of the Third Schedule.

(4) The units specified in the second column of the Fourth Schedule may be used for the measurement of the corresponding quantity specified in the first column of that Schedule.

4. Multiples and sub-multiples

(1) Subject to subsections (2) and (3), the multiples and sub-multiples of the units mentioned in section 3 shall be those specified in the first column of the Fifth Schedule.

(2) The multiples and sub-multiples of the units of mass shall be ex- pressed by using the prefixes and symbols specified in the Fifth Schedule in relation to the word “gram”, which is represented by the symbol “g”.

(3) (a) Any multiple or sub-multiple of a unit mentioned in section 3, other than that specified in the Fifth Schedule, shall be expressed in powers of 10 or in terms of a decimal function.

(b) For the purposes of paragraph (a), the decimal sign shall be indi- cated by a point.

5. Symbols and prefixes

No person shall, in relation to any unit mentioned in section 3, its multiple or sub-multiple, use a symbol or prefix, other than the symbol or prefix speci- fied in the appropriate Schedule.

Revised Laws of Mauritius

I19 – 3 [Issue 1]

6. Regulations

The Minister may— (a) make such regulations as he thinks fit for the purposes of this

Act; (b) by regulations, amend the Schedules.

7. Offences

Any person who fails to comply with this Act or any regulations made under it shall commit an offence and shall, on conviction, be liable to a fine not exceeding 2,000 rupees and to imprisonment for a term not exceeding one year.

8. —

9. Application of Act

This Act shall not apply to any measurement of quantity— (a) in respect of a vessel for the purposes of any tax, licence, fee or

dues; (b) in sea or air navigation or meteorology.

10. The State

This Act shall bind the State. [S. 10 amended by Act 48 of 1991.]

11. —



FIRST SCHEDULE [Section 3 (3) (a)]

Quantity Base unit Symbol Definition length ............................ metre ................. m ......... The metre is the distance

travelled by light in a vac- uum during 1 299 792 458 of a second.

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

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

International System of Units (SI) Act

[Issue 1] I19 – 4

FIRST SCHEDULE—continued

Quantity Base unit Symbol Definition electric current ............... ampere ................ A ......... The ampere is that con-

stant current which, if maintained in 2 straight parallel conductors of infi- nite length, of negligible circular cross-section, and placed one metre apart in vacuum would produce between these conductors a force equal to 2 x 10-7

newton per metre length of conductor.

thermodynamic temperature ...... kelvin ........ K ......... The kelvin, unit of thermo- dynamic temperature, is the fraction 1/273.16 of the thermodynamic tem- perature of the triple point of water.

luminous intensity .......... candela .............. cd ........ The candela is the lumi- nous intensity in a given direction of a source which emits monochromatic ra- diation of frequency 540 x 1012 hertz and of which the radiant intensity in that direction is 1/683 watt per steradian.

amount of substance ........ mole ............... mol ........ The mole is the amount of substance of a system which contains as many elementary entities as there are atoms on 0.012 kilogram of carbon-12. 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.



Revised Laws of Mauritius

I19 – 5 [Issue 1]

SECOND SCHEDULE [Section 3 (3) (b)]

Quantity Supplementary unit

Symbol Definition

plane angle ..................... radian ............... rad ........ 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.

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



THIRD SCHEDULE [Section 3 (3) (c)]

Quantity Derived unit Symbol Definition in terms of

other SI units frequency .................................................. hertz Hz 1/s force ......................................................... newton N mkg/s2 pressure .................................................... pascal Pa N/m2 energy, work, quantity of heat ..................... joule J Nm power, energy flux ..................................... watt W J/s quantity of electricity, electric charge ............ coulomb C As electric tension, electric potential .................. volt V W/A electric capacitance .................................... farad F C/V electric resistance ....................................... ohm W V/A conductance .............................................. siemens S A/V magnetic flux ............................................. weber Wb Vs magnetic flux density .................................. tesla T Wb/m2 inductance ................................................. henry H Wb/A luminous flux ............................................. lumen lm cdsr illuminance ................................................ lux lx cd sr/m2 activity (radioactive) ................................... becquerel Bq 1/s absorbed dose (of ionising radiation) ............. gray Gy J/kg dose equivalent (of ionising radiation) ............ sievert Sv J/kg



International System of Units (SI) Act

[Issue 1] I19 – 6

FOURTH SCHEDULE [Section 3 (4)]

Quantity Name of unit Symbol Equivalent plane angle ........................... degree –º 1º = (p/180) rad arcminute –' 1' = (1/60)° arcsecond –" 1” = (1/60)' area ..................................... hectare ha 1 ha = 104m2 volume ................................. litre L* 1 L = 1 dm3 *The symbol R is also

permitted for litre. time ..................................... day d 1 d = 24 h hour h 1 h = 60 min minute min 1 min = 60 s velocity kilometre per hour km/h – flow rate .............................. litre per second L/s –

(volume basis) rotational frequency ............... revolution per

second r/s –

revolution per minute

r/min 1 r/min = 1/60 r/s

mass ................................... tonne t 1 t = 103kg metric carat CM 1 CM = 0.2 g linear density ........................ tex tex 1 tex = 1 g/km

(mass per unit length) flow rate .............................. tonne per second t/s –

(mass basis) ....................... tonne per hour t/h – dynamic viscosity .................. poise P 1 P = 0.1 Pa. s kinematic viscosity ................ stoke St 1 St = 100 mm2/S energy, work ........................ watt hour Wh 1Wh = 3.6 kJ temperature .......................... degree Celsius ºC The Celsius tempera-

ture (t) is equal to the difference between the thermodynamic temperature T and 273.15 K

electric charge, quantity of electricity .......................... ampere hour Ah 1 Ah = 3.6 kC

apparent power ..................... volt ampere VA – reactive power ...................... var var var 1 var - 1 VA reac-

tive power molar volume ........................ litre per mole L/mol

Revised Laws of Mauritius

I19 – 7 [Issue 1]

FOURTH SCHEDULE—continued

Quantity Name of unit Symbol Equivalent sound power level ................. decibel dB The sound power level

in decibels is equal to 10 times the logarithm to the base 10 of the ratio of the measured power to a reference sound power (1 pW).

concentration ........................ mole per litre mol/L pressure ............................... bar bar 1 bar = 100 kPa millimetre of

mercury mm Hg 1 millimetre of Mer-

cury = 133.322 Pa [Fourth Sch. amended by GN 80 of 1989.]



FIFTH SCHEDULE [Section 4]

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



International System of Units (SI) Act

[Issue 1] I19 – 8

SIXTH SCHEDULE [Section 8]

Unit Equivalent Size in appropriateSI unit Expiry period

inch (in) ............... – .......................... 0.025 4 m foot (ft) ................ 12 inches ................ 0. 304 8 m yard (yd) .............. 3 feet .................... 0.914 4 m mile ..................... 1760 yards .................. 1609.344 m pouce (French) ...... – .......................... 0.027 070 1 m2 2 years pied (French) ......... 12 pouces (French) ... 0.324 841 m toise .................... 6 pieds (French) ...... 1.949 05 m gaulette (length) .... 10 pieds (French) ...... 3.248 41 m perche ................. 2 gaulettes ............. 6.496 82 m Unit of area square inch (in2) .... – .......................... 0.000 645 16 m2 square foot (ft2) .... 144 square inches ...... 0.092 903 0 m2 square yard (yd2) ... 9 square feet .......... 0.836 127 m2 square mile (mile2) .. – .......................... 2.589 99 km2 pied carré (French).. – .......................... 0.105 522 m2 toise carrée .......... 36 pieds carrés

(French) .............. 3. 798 78

m2

2 years

perche carrée ........ 400 pieds carrés (French) ............... 42.

208 7

m2



arpent .................. 100 perches carrées (French) .............. 4 220.

87

m2



gaulette (area) 10x5 pieds carrés (French) .............. 5.

276 09

m2



Unit of volume cubic inch (in3) ...... – .......................... 16.387 1 cm3 cubic foot (ft3)1 .... 1 728 cubic inches ........ 0.028 316 8 m3 cubic yard (yd3) ..... 27 cubic feet ........... 0.764 555 m3 UK fluid ounce ...... – .......................... 28.413 1 cm3 UK pint ................ 20 UK fluid ounces ... 0.568 261 dm3 1 year UK quart .............. 2 UK pints ............. 1.136 52 dm3 UK gallon ............. 4 UK quarts ........... 4.546 09 dm3 peg ...................... – .......................... 46 cm3 topette ................. – 50 cm3 Unit of volumetric flow rate .............. pouce fontainier ..... 0.007

833 cubic foot/second 21.805 cm3/s 1 year

Unit of mass ounce (oz) ............ – .......................... 28.349 5 g

Revised Laws of Mauritius

I19 – 9 [Issue 1]

SIXTH SCHEDULE—continued

Unit Equivalent Size in appropriate SI unit

Expiry period

UK (and US) ............. 16 ounces.............. 0.453 592 37 kg pound (lb)

UK (long) ton ........... 2 240 pounds ............. 1 016.05 kg UK (short) ton .......... 2 000 pounds ............. 907.185 kg 1 year UK (and US) ............. – ........................ 31.103 5 g

ounce troy tola ......................... – ........................ 10 g

Unit of force pound force (lbf)*....... – ........................ 4.448.22 N 5 years kilogram force (kgf)*.. – ........................ 9.806.65 N

Unit of pressure pound force per square inch (lbf/in2 or psi)* ... – ........................ 6 894.76 Pa kilogram force per square cm (kgf/cm2)* ................

technical atmos- phere ............... 98 066.5 Pa 5 years

Unit of power metric horse power – ........................ 735.499 W 5 years

UK horse power .......... – ........................ 745.700 W [Sixth Sch. amended by GN 80 of 1989.]

* Sizes in appropriate SI units for these units have been calculated assuming a value of 9.806 65m/s2 for the acceleration due to gravity.