| Mold |
| Mold are commonly found in outdoor air and greatly outnumber pollen grains. Outdoor airborne mold can easily invade your home. Any house can develop a mold problem, given the right conditions. You might not see it growing on the walls, but it may still be present in your home. Mold require two main factors to grow indoors: |
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Free moisture that can occur in the form of relative humidity above 50 percent, leakage from pipes or foundations, clogged condensate or drip pans, or any ongoing source of water. |
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Something to grow on. Molds particularly like to grow on wallboard, wood or fabrics, but will grow virtually any place if they are given a chance. |
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| Mold spread by producing spores that can become airborne. These spores end up in house dust where they grow. |