The Units of Measurement Regulations 2009

SCHEDULESubstituted paragraph 2(3) for Schedule 1 to the Units of Measurement Regulations 1986

(3) SI derived units with special names and symbols

QuantityUnit NameUnit SymbolExpression in terms of other SI unitsExpression in terms of SI base units
Plane angleradianradm.m-1
Solid anglesteradiansrm2.m-2
FrequencyHertzHzs-1
ForcenewtonNm.kg.s-2
Pressure, stresspascalPaN.m-2m-1.kg.s-2
Energy, work, quantity of heatJouleJN.mm2.kg.s-2
Power*, radiant fluxWattWJ.s-1m2.kg.s-3
Electric charge, quantity of electricitycoulombCs.A
Electric potential, potential difference, electromotive forceVoltVW.A-1m2.kg.s-3.A-1
Electric resistanceOhmV.A-1m2.kg.s-3.A-2
ConductancesiemensSA.V-1m-2.kg-1.s3.A2
CapacitanceFaradFC.V-1m-2.kg-1.s4.A2
Magnetic fluxweberWbV.sm2.kg.s-2.A-1
Magnetic flux densityTeslaTWb.m-2kg.s-2.A-1
InductanceHenryHWb.A-1m2.kg.s-2.A-2
Luminous fluxlumenlmcd.srcd
IlluminanceLuxlxlm.m-2m-2.cd
Activity (of a radionuclide)becquerelBqs-1
Absorbed dose, specific energy imparted, kerma, absorbed dose indexGrayGyJ.kg-1m2.s-2
Dose equivalent, dose equivalent indexsievertSvJ.kg-1m2.s-2
Catalytic activityKatalkatmol.s-1

Notes

Units derived from SI base units may be expressed in terms of the units listed in this Schedule.

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.

*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.