The air inside your home can be 5 times as polluted as the air outdoors. As homes became tighter and more energy efficient this allowed for the accumulation of air pollutants such as allergens, dust mites, volatile organic compounds, and other irritants.
There are a few main strategies to improve IAQ
First way is to control the source of the irritant. Remove items that may be out-gassing formaldehyde, have serviced or repaired appliances that have the potential for effecting the indoor air such as a gas water heater or gas cook stove that is not functioning properly. Try not to use those chemical air freshers. They contain chemicals that can be irritants.
Control Moisture. If you have too much moisture in the home then the home can have conducive conditions for mold growth. Molds definitely contribute to unhealthy air quality. In Ohio with the winters we get indoor humidity can condense in interior walls helping molds to grow. This can especially occur in closets where one of the walls is an exterior wall and get cold enough to reach dew point.
Improve ventilation of the home. Bring more fresh air in to the home. Open some windows when the weather is nice outside. Even if only for an hour or so do it, the fresh air will be nice. If possible open enough windows to get a cross breeze to help exchange the air. Opening upper level windows and lower level windows will help create a chimney effect and air out the entire home better.
Use air cleaners. Having an air filter and an air cleaner is a nice way to help filter and trap particles that are floating in the air. If you have pets then you know how much animals can contribute to this.
Clean your ducts. Dirty hvac duct work is something that home inspectors find often. Home inspectors only can see the area immediately near the registers however there are long sections in which can not be seen, and rarely do home owners or home sellers get those professionally cleaned.
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