Measure humidity with a gauge. Tightly closed houses encourage mold growth. Empty water pans below self-defrosting refrigerators, and clean garbage cans frequently. Do not carpet your bathroom. Avoid foam rubber, which is likely to become moldy.
Mold grows well in damp, dark closets.
A low-watt light bulb can help prevent mold growth in closets. Kapok and jute, two common tropical fibers, are common reservoirs for mold. Kapok is an Indonesian fiber that is stuffed into life jackets, sleeping bags, cushions, and pillows. One test, by Richard Harris, a Beverly Hills allergist, found that ten patients out of fifty-nine were allergic to kapok, and nine were allergic to jute. Portable units are usually not effective.