Understanding Indoor Air Quality 

Pollutant Problems

All homes, no matter how clean they appear, are contaminated with dirt and dust.  

Older homes can be breeding grounds for mold and mildew. 
New, tightly sealed homes trap pollutants and can have higher concentrations of chemicals

Types & Sources of Pollutants 

	Type Particles	Definition Pollutants found in the air	Pollutants  • Pollen  • Dust mites  • Dirt  • Pet and human dander	Sources  • Plants, people and animals
	Microorganisims/Bioaerosols	Microscopic pollutants that grow and reproduce in warm, humid environments	• Viruses  • Mold spores  • Fungi	• Plants, people, and animals  • Ductwork  • Humidifier drip pans  • Shower heads and toilets  • HVAC Systems that have not been properly maintained  • Plumbing leaks  • Dampness in basements, crawl-spaces, attics and bathrooms
	Odors/Chemical Vapors	Air Contaminants in the form of gases	• Pet odors  • Cooking smells  • Gasoline fumes  • Volatile organic compounds (VOC's), such as formaldehyde  and gasoline  • Carbon Dioxide  • Carbon Monoxide	• Cleaning supplies  • Paints and solvents  • Perfumes  • Tobacco smoke  • Carpeting and upholstery  • Air fresheners  • Automotive fuel and supplies  • Dry-cleaned clothing  • Stoves, heaters and fireplaces  • Pesticides and herbicides
	Humidification Maintaining proper humidity levels, between 35% and 50%, has a significant impact on overall indoor air quality.