Units

A catalog of physical units and quantity kinds ("length" would be the quantity kind for the units "metre", "inch", "millimetre" and so on) is part of the Aspect Meta Model. As such, the unit catalog is provided in a machine readable fashion. The catalog is based on the UNECE Recommendation 20 [rec20] and comprises about 1,800 units. The units are used in Characteristics such as Measurement and Duration. The full catalog is available in tabular form in Appendix Unit Catalog. Please note that, while in principle preferred names in multiple languages can be added to quantity kinds and units, the catalog provides preferred names in english only.

The unit names in UNECE Recommendation 20 (and therefore in the units catalog) are given in British English, e.g., metre, not meter.

A quantity kind has the following attributes:

Attributes Description Present in every quantity kind

bamm:name

Unique name of quantity kind

bamm:preferredName

Human readable name in a specific language

A unit has the following attributes:

Attributes Description Present in every unit

bamm:name

Unique name of unit

bamm:preferredName

Human readable name in a specific language

unit:commonCode

Normalized short code for unit; please refer to the original specification for more details

[1]

unit:conversionFactor

If the unit is derived from a reference unit, the human readable multiplication factor, e.g., "10⁻²⁸ m²"

unit:numericConversionFactor

If the unit is derived from a reference unit, the numeric multiplication factor, e.g., "1.0E-28"

unit:quantityKind

The list of quantity kinds, for example unit litre has quantity kind volume, unit metre has quantity kinds length, distance, diameter etc.

unit:referenceUnit

The unit this unit is derived from, e.g., centimetre is derived from metre

unit:symbol

The unit’s symbol, e.g., for centimetre the symbol is cm

1. Every unit originating from UNECE Recommendation 20 has a commonCode defined by the standardization process, units added in the scope of the BAMM therefore do not have one. For example, no commonCode is added to unit:cubicMicrometre.