Fact: 9 out of 10 system failures are caused by dirt and dust. Louisiana Cooperative Extension Service

Fact: Clean systems restore capacity and lessen running time. Translation: Savings on your monthly heating/cooling bills. Louisiana Cooperative Extension Service

Fact: A buildup of .042 inches of dirt on a heating or cooling coil can result in a decreased efficiency of 21%. Environmental Protection Agency

Fact: Most commonly purchased fiberglass filters are only 7% efficient in stopping dirt, dust, pollen, etc. passing through it. American Society of Heating, Refrigerating and Air-Conditioning Engineers

Fact: 50% of all illnesses are either caused or aggravated by polluted indoor air. American College of Allergists

Fact: One out of six people who suffer from allergies do so because of the direct relationship to the fungi and bacteria in air duct systems. Total Health and Better Health Magazines

Fact: Legionnaire's Disease was spawned in air conditioning ducts. It killed 29 people in 1976. American Lung Association

Fact: In the summer of 1988 at least 7 people died in the Los Angeles area from Legionnaire's Disease. Modesto Bee 9/22/88

Fact: Children are more likely than adults to be affected by polluted indoor air-they breathe faster, inhale more air per unit of body weight and are closer to the ground where concentrations of bacteria are higher. Department of Consumer Affairs

Fact: The elderly asthmatics, and people with breathing problems, allergies and lung diseases are also likely to be more sensitive to pollutants. Department of Consumer Affairs

Fact: Most people spend 60-90% of their time indoors. American Lung Association

Fact: Indoor air is found to be up to 70 times more polluted than outdoor air. Environmental Protection Agency