To improve indoor air quality, reduce or remove the source of the pollutants. For example, paints, solvents or other chemicals should not be stored in the home but rather in a garage or shed. If the garage is attached to the home, make sure there is an airtight seal between the garage and living quarters. This will prevent pollutants from entering the house. Another safeguard is to use building materials and cleaning products with a low level of toxicity.
Unfortunately, indoor pollutants are virtually impossible to eliminate completely, creating the need for a second step to improve indoor air quality-mechanical ventilation. Mechanical ventilation is used to remove stale, moist, polluted air and replace it with fresh outside air.
Sometimes referred to as general, central, whole-house or primary ventilation, continuous ventilation is used to remove stale air and provide fresh air on a slow, continuous basis. A well-designed airtight home can generally use low volume continuous ventilation.
Sometimes referred to as spot, local or secondary ventilation, intermittent ventilation is used to capture and remove pollutants quickly at the source. Pockets of excessive moisture and pollutants can build up in the bathroom, kitchen, utility room, garage and home office. This secondary process serves to exhaust these problem areas quickly, before “bad air” can spread throughout the house. Just as important as continuous ventilation, intermittent ventilation complements the effort to improve indoor air quality.
Intermittent ventilation quickly ventilates contaminated areas and often uses less energy, which results in less exposure to occupants than the slower continuous ventilation process. Both systems exhaust pollutants from the air, but intermittent ventilation is more effective in concentrated areas.
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