Get your indoor humidity right

"How's your humidity?" No one's probably asked you that before. But with the cold air coming this weekend, let's talk about indoor humidity. It actually has a lot to do with how comfortable you feel.

Enter the classroom and grab a seat for "Humidity 101."

You probably have heard that humidity is a relative thing. That is why your friendly Meteorologist always says "the relative humidity is now...per cent." As you heat a constant volume of air it can hold more moisture. When it becomes saturated, the relative humidity reaches 100%. Now let's think about the process of cooling and warming the air. During the summertime, most air conditioners will produce a few drips of water. That's because water is a byproduct of cooling. The same is inversely true. When we heat the air inside our homes during the winter, water is taken out of the air.

If the air temperature outside is 0°F and we bring that air inside and heat it to 70° we're left with only 5% relative humidity! Without a humidifier in your home, you're sure to have cracked joints, chapped lips, and dry skin.

Here's the correct humidity for winter.

Outside temperature (degrees fahrenheit)	Recommended relative humidity
+20° and above	35% to 40%
+10°	30%
0°	25%
-10°	20%
-20°	15%

If you REALLY want to know the exact humidity inside your home, you can buy an inexpensive hygrometer at RadioShack.

Indoor / Outdoor Thermometer with Hygrometer Model #63-1032 - Displays interior temperature, exterior temperature and relative humidity and humidity comfort readings. Electronic. Requires 2 AA batteries. $19.99