2003 November 6
Terry,
In 27470 you say Tables 6+ are not SI. Why do you say this?
What they are not is coherent with SI.
For us who know the technical stuff of SI that comes from CIPM
through BIPM, we can say litre is not SI where we mean that it is
not coherent (and we know what coherent means).
As for the general public we should not be so stupid as to say
litre and millimetre are not SI. We have a good system of units,
a decimal system of units. BIPM lists units in use with SI,
meaning units that are not coherent that can be used with SI.
What do we gain by saying these 'outliers" are not SI?
For USMA the goal is to get the USA to change to SI. Let us not confuse
this with details about coherent. Let us not be picky with the public.
Robert Bushnell
chair ASTM committee E43 on SI Practice
