[1] UCUM is used by different organizations like IEEE, and standards like DICOM, LOINC, HL7, and ISO 11240:2012.
[2] The code set includes all units defined in ISO 1000, ISO 2955-1983,[3][a] ANSI X3.50-1986,[4][b] HL7 and ENV 12435, and explicitly and verifiably addresses the naming conflicts and ambiguities in those standards to resolve them.
[5] The UCUM base units are the metre for measurement of length, the second for time, the gram for mass, the coulomb for charge, the kelvin for temperature, the candela for luminous intensity, and the radian for plane angle.
The UCUM base units form a set of mutually independent dimensions as required by dimensional analysis.
Each unit represented in UCUM is identified as either "metric" or "non-metric".