Resolution 12 of the 11th CGPM (1960)
Système International d'Unités
The 11th Conférence Générale des Poids et Mesures (CGPM),
considering
- Resolution 6 of the 10th CGPM, by which it adopted six base units on which to establish a practical system of measurement for international use:
length metre m mass kilogram kg time second s electric current ampere A thermodynamic temperature degree Kelvin °K luminous intensity candela cd - Resolution 3 adopted by the Comité International des Poids et Mesures (CIPM) in 1956,
- the recommendation adopted by the CIPM in 1958 concerning an abbreviation for the name of the system, and prefixes to form multiples and submultiples of the units,
decides
- the system founded on the six base units above is called the "Système International d'Unités";
- the international abbreviation of the name of the system is SI;
- names of multiples and submultiples of the units are formed by means of the following prefixes:
Multiplying factor Prefix Symbol 1 000 000 000 000 = 1012 tera T 1 000 000 000 = 109 giga G 1 000 000 = 106 mega M 1 000 = 103 kilo k 100 = 102 hecto h 10 = 101 deca da Multiplying factor Prefix Symbol 0.1 = 10–1 deci d 0.01 = 10–2 centi c 0.001 = 10–3 milli m 0.000 001 = 10–6 micro µ 0.000 000 001 = 10–9 nano n 0.000 000 000 001 = 10–12 pico p - the units listed below are used in the system, without excluding others which might be added later.
Supplementary units
| Plane angle | radian | rad |
| Solid angle | steradian | sr |
Derived units
| area | square metre | m2 | |
| volume | cubic metre | m3 | |
| frequency | hertz | Hz | 1/s |
| mass density (density) | kilogram per cubic metre | kg/m3 | |
| speed, velocity | metre per second | m/s | |
| angular velocity | radian per second | rad/s | |
| acceleration | metre per second squared | m/s2 | |
| angular acceleration | radian per second squared | rad/s2 | |
| force | newton | N | kg · m/s2 |
| pressure (mechanical stress) | newton per square metre | N/m2 | |
| kinematic viscosity | square metre per second | m2/s | |
| dynamic viscosity | newton-second per square metre | N · s/m2 | |
| work, energy, quantity of heat | joule | J | N · m |
| power | watt | W | J/s |
| quantity of electricity | coulomb | C | A · s |
| tension (voltage), difference, electromotive force | volt | V | W/A |
| electric field strength | volt per metre | V/m | |
| electric resistance | ohm | Ω | V/A |
| capacitance | farad | F | A · s/V |
| magnetic flux | weber | Wb | V · s |
| inductance | henry | H | V · s/A |
| magnetic flux density | tesla | T | Wb/m2 |
| magnetic field strength | ampere per metre | A/m | |
| magnetomotive force | ampere | A | |
| luminous flux | lumen | lm | cd · sr |
| luminance | candela per square metre | cd/m2 | |
| illuminance | lux | lx | lm/m2 |
DOI : 10.59161/CGPM1960RES12E
The reader should note that the official version of this Resolution is the French textNOTE
The CGPM later abrogated certain of its decisions and extended the list of prefixes:
- The name and symbol for the unit of thermodynamic temperature were modified by the 13th CGPM in 1967 (Resolution 3).
- A seventh base unit, the mole, was adopted by the 14th CGPM in 1971 (Resolution 3).
- Further prefixes were adopted by the 12th CGPM in 1964 (Resolution 8), the 15th CGPM in 1975 (Resolution 10), the 19th CGPM in 1991 (Resolution 4) and the 27th CGPM in 2022 (Resolution 3).
- The 20th CGPM in 1995 abrogated the class of supplementary units in the SI (Resolution 8). These are now considered as derived units.
- The 13th CGPM in 1967 (Resolution 6) specified other units which should be added to this list of derived units. In principle, the list is without limit.
- Modern practice is to use the phrase "amount of heat" rather than "quantity of heat", because the word quantity has a different meaning in metrology.
- Modern practice is to use the phrase "amount of electricity" rather than "quantity of electrcity" (see above).
