*Mismatch of base units between UCUM and SI

[timbrisc]

Issue migrated from trac ticket # 5788

component: help | priority: major

2021-03-01 00:00:06: [email protected] created the issue

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The seven 'base units' in UCUM do not match the SI. See https://ucum.org/ucum.html#section-Base-Units for UCUM, and compare with https://www.bipm.org/en/measurement-units/ and select tab 'SI base units'.

Amount of substance/mole missing from UCUM base quantities/units. Plane angle is not a base quantity in SI.

I note that this deviation is discussed and justified in the UCUM spec, but it presents a barrier to advocating for the use of UCUM in the context of SI.