my hygrometer accurate?
There is an easy way to determine if your hygrometer is accurate.
You need a ziploc bag, a screw-on soda bottle cap (or other small
container) a small amount of salt, and water.
Place the salt in the bottle cap (or other small container).
2. Dampen the salt with water. Do not put so much that the salt is
"sloppy". You want a damp pile of salt in the bottle cap.
3. Place both the hygrometer, and the bottle cap full of damp salt
in the ziploc bag and seal it well. (It is important not to let air
on or out while the test is going on.)
4. Let everything sit like this for over 8 hours.
8 hours in the damp salt environment, the hygrometer should read
75%. If it does not, note the amount and direction that it actually
reads and be sure to add or subtract that amount when reading the
hygrometer. If the hygrometer has a control to adjust it (either the
needle or the display), you can set the hygrometer to 75%
immediately after the test.
should salt test your hygrometer every 6 months or so to be sure of
Courtesy of Cigarado.com