Begin by touring your household. Follow your nose and use your eyes. During your walk-through, look for such conditions, and plan ways to make improvements. A musty odor, moisture on hard surfaces, and water stains are a sign of water leaks or condensation. Dust and construction materials, such as wood, wallboard, and insulation, contain nutrients that allow biological pollutants to grow, and must be kept clean and dry.
Carpet absorbs moisture and nutrients, and is an ideal environment for biological pollutants.
Pay special attention to carpeting on cool concrete floors, where moisture can condense and become trapped. Firewood is also a source of moisture, fungi, and bugs, and should be stored outdoors. A healthy dose of common sense is the best way to control the spread and multiplication of biological agents. Regular and thorough cleaning of places where biological pollutants are likely to grow will keep them at a minimum. You will never be able to get rid of biological agents totally, but you can inhibit their growth.