Lowell:
If your needs are for definite accuracy, you have to use the "correct" tools,
not guess work, so you use a calibrated refractometer to measure honey
moisture.

You would not try to weigh aspirin tablets on a bathroom weight scale, nor
would you use a 1 pound honey jar to as a gasoline emergency can to fill your
car gas tank.

However, by PROPERLY extracting your honey, you will avoid high moisture.
Back in the "good old days", before all Americans were in a mad rush for
everything, the was very little use for a refractometer because beekeepers
were not RUSHED to market.
The MAJOR MISTAKE is extracting honey that is not FULLY CAPPED.  Honey bees
do not cap the honey until the honey is totally cured and hence below 18.6%
moisture content.  These "not so careful" beeHAVERS, will extract all ten
super frames when
only about 6-8 of them are fully capped and the others maybe have 10-20% open
cells, and these "small apples" spoil the whole barrel.
Another major mistake is the beekeeper leaving extracted honey just sitting
in an
uncovered container while it is settling or waiting to be bottled.  Honey is
very hygroscopic and absorbs moisture right out of the air, particularly in
my high humidity area of Washington, DC.
If you observe the PROPER techniques for extracting and protecting your honey
from exposure to humid air, your honey will normally be OK and not ferment.
I admit, since I am a retired scientist, I naturally use a refractometer,
just to be sure; but few do.

If I can further help, write me.  Also, you can find my famous PINK PAGES on:
http://www.beekeeper.org/george_imirie/index.html


        George Imirie