Mike Joy wrote in USMA 23968:
Bill Potts said:-| The SI derived unit (not "derivative") for pressure is pascal (Pa). Hecto | and kilo are both valid prefixes. There is nothing I know of in SI that | states a preference for kilopascals over hectopascals.
I believe it is an engineering convention to restrict prefixes in engineering drawings to milli-, kilo-, mega-, In that way there is less danger of confusion, and each individual dimension does not need to have its unit indicated.
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Joseph B. Reid
17 Glebe Road West
Toronto M5P 1C8 Telephone 416-486-6071
