enum IFCUnit { AbsorbedDoseUnit, AmountOfSubstanceUnit, AreaUnit, DoseEquivalentUnit, ElectricCapacitanceUnit, ElectricChargeUnit, ElectricConductanceUnit, ElectricCurrentUnit, ElectricResistanceUnit, ElectricVoltageUnit, EnergyUnit, ForceUnit, FrequencyUnit, IlluminanceUnit, InductanceUnit, LengthUnit, LuminousFluxUnit, LuminousIntensityUnit, MagneticFluxDensityUnit, MagneticFluxUnit, MassUnit, PlaneAngleUnit, PowerUnit, PressureUnit, RadioActivityUnit, SolidAngleUnit, ThermoDynamicTemperatureUnit, TimeUnit, VolumeUnit, UserDefined };