Indoors and out, mold spores’ ideal landing pad is one with moisture, air and organic matter to serve as food. This combination of conditions can be found everywhere from furnishings stored in damp conditions to cardboard boxes that come in contact with subterranean concrete floors or wood shelves. One of the biggest and most often overlooked havens for mold is the air conditioner, whether a humble portable or mighty central air setup.
The irony is that you’re told to put in air conditioning for asthma and allergy problems, and in one way it’s helpful, but in another way it can be detrimental. An air conditioning coil and everything around it is damp while the machine is running, so unless the surfaces are absolutely 100 percent clean, mold is going to grow. It’s almost inevitable that if somebody has an air conditioning system or a portable air conditioner and they don’t use adequate filtration, they’re going to get mold. So the single most important thing for all air conditioning is to use a decent filter.”
That means a pleated filter with a MERV (Minimum Efficiency Reporting Value) rating of at least 8, or 11 if your family is prone to allergies. May also notes that in the case of a window AC unit, the filter it’s shipped with usually has a MERV rating far lower than 8, so an immediate filter upgrade is in order.
Basements are the other major household mold zones, and call for careful humidity control. Keep the humidity level below 50 percent, and to further combat mold attraction, keep finished below-grade spaces heated to at least 60 degrees around the clock. Also make sure that the grading and drainage patterns outside your home aren’t ushering in potential moisture and mold problems, and that ventilation is vigorous and properly directed outside.
The bottom line is that molds are ubiquitous (they can be anywhere at anytime of year), and they can cause a tremendous number of pathologic conditions. See our information on fungal sinusitis and yeast conditions .