(ARA) – As soon as the temperatures warm up, you open up the doors and windows and let the “fresh” air in. Many people go on a cleaning spree, vacuuming, dusting and getting rid of all the dust bunnies hiding under furniture. With a fresh, clean house, you assume you’ll be breathing much easier.

Think again. Air pollution is a very serious concern indoors. The U.S. Environmental Protection Agency lists poor indoor air quality as one of the top five environmental threats. It also reports indoor air is three to five times more contaminated than outdoor air, on average.

“When warm weather rolls around, and the natural thing to do is open up your windows and bring new air into your house,” says Matt Mongiello, president of the National Air Duct Cleaners Association. “However, this is when allergy season is at its highest, and you’re welcoming new pollutants into your home and contaminating your air with pollens.”

These pollutants are then blown through your house five to seven times each day by your heating, ventilation and air conditioning system. And the cleaning you’re doing? All those dust bunnies are just groupings of millions of little particles of dust, dander and pollen. When broken up, many of the particles go back into the air, circulate around through your house and once again collect under your sofa.

Some tips to keep the air you breathe inside as clean as possible include:

* Install hardwood floors versus carpeting. Carpeting traps particles, and with every step you take across it, those particles are released back into the air.

* Have carpets professionally cleaned with a truck-mounted system.

* Use natural- or botanical-based cleaners instead of chemicals.

* Regularly change your furnace filter – most experts recommend doing this every two months. This will help remove particles circulating through the air.

* Have your heating and cooling system thoroughly cleaned. This is because dust and other air pollutants collect in the vents, and then are picked up by the air stream and blown back into the house.

NADCA recommends homeowners take off the cover of an air vent and look down the vent with a mirror and flashlight or a digital camera. If the ducts are covered with dust or debris, it’s time for a heating and cooling system cleaning.

NADCA recommends a thorough duct cleaning, as well as cleaning the evaporator coil and all parts of the system that air touches. Not only will this clean up the air inside your house, but it will also help your system work more efficiently and save you money. A study taken by Pacific Gas and Electric showed that a dirty condenser coil can result in 30 percent higher energy usage. To find a qualified heating and cooling system cleaner in your area, visit NADCA.com.