Re: SI and all that

[Christoph_Hofmeyr/CNS1@cns.co.za]

Radsafers,
C'mon, US, would you be happy if we measured speed in furlongs per
fortnight?   Are you really happy that a mile is 1760 yards?  In fact, in
RP (sorry, Health Physics) units you are more than half-way there, having
adopted the Napoleonic CGS system - it is only a small step to SI, and may
be a giant leap for mutual understanding.  OK, except for Ci, it is just a
question of shifting the decimal point, and ten millisieverts sound less
than a rem.  It basically started with Napoleon, who felt obliged to
conquer most of Europe and part of Russia to get them to adopt the metric
system.     Take heart, there is no such danger when shifting from cgs to
SI - because you have already taken the big step, which would have
gladdened the Corsican's heart.   Not even the Brits have bothered with
Imperial radiation units, that I know of.  With SI you must buy the
package, not think rad and say centiGray.  That is arcane.  You must learn
to think in factors of a thousand, so out go the beloved cm and prefixes
like deci- and centi-.  Having been conceived and born into the 'sinful'
Imperial system of miles, yards, feet, inches and eighths, sixteenths up to
sixty-fourths and -surprise- mils, and half converted to CGS, I was
horrified when I had to submit building plans in millimeters (NOT cm),
until I cottoned on to the rule of thousands - then suddenly peace
descended.   Of course, SI is not perfect - most glaringly with the
kilogram being the unit of mass - why not Newgram?  But gradually you
realise it has not been invented by boneheads.  American CHPs want to make
a last stand at the wrong trench, but this is strictly my own opinion.
Chris Hofmeyr
chofmeyr@cns.co.za


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