I've seen quite a few engineers here in the U.S. use nF or nH.

In my view, there never was a good reason for *not* using the nano- prefix.
We always used it for nanoseconds, and it was always used in scientific
work as distinct from electronics.

On schematics, I prefer to avoid decimal points entirely, using 6N2 to
represent 6.2 nanofarads, for example.

I'd use millifarads if there were a nice unambiguous prefix and there were
any tradition in the industry of using them. Had we consistently used u-
for micro -- as did the scientists -- instead of the anomalous m- for
micro-, we would then be able to use m- for milli, at least with farads, as
well as ohms.

Being able to use upper and lower case, again, as the scientists do, allows
a full range of unambiguous multipliers:

a- atto, 10^-18
f- femto, 10^-15
p- pico, 10^-12
n- nano, 10^-9
u- micro, 10^-6
m- milli, 10^-3
k- kilo, 10^3
M- mega, 10^6
G- giga, 10^9
T- tera, 10^12

Nobody seems to use:

c- centi, 10^-2
d- deci, 10^-1
da- deka, 10
h- hecto, 10^2

except, of course, for centimeter or hectare (100 ares; an are is, somewhat
weirdly, 100 square meters). Those prefixes are from my old Handbook of
Chemistry and Physics; I'd have chosen D- for deka to be more
consistent.... (and K- for kilo as well). But international standards are
just that.... Have they changed?


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Abdulrahman Lomax
P.O. Box 690
El Verano, CA 95433