It's enough to make you cough. But don't panic. By taking a few simple steps, you can improve your indoor air quality and make your home cleaner and cozier. Here are some solutions from the Home Comfort Institute at Trane, the leading maker of energy-efficient heating, ventilating and air conditioning systems, to help you improve your home air quality during the cold winter months:

- Change your air filter. Dealing with winter indoor air quality most effectively means filtering or cleaning all the air in the home using the heating system.

Most furnaces come with a 1-inch disposable filter that traps and filters out large airborne particles. During winter heating season, these filters can become covered with dust and particles. Trane recommends changing this filter monthly during the heating season to ensure it is operating effectively. These filters cost just a few dollars and are available at all home improvement stores.

"Regular filter changes help keep your system running efficiently, but they won't do much to help clean the indoor air," said Robert Helt, director of the Trane Home Comfort Institute. "For that you need an air cleaner designed specifically to clean indoor air throughout the entire home."

- Upgrade your filter system. The 1-inch filter on most systems traps relatively large airborne particles, but it catches less than five percent of total particles. The most effective filtration product is an electronic air cleaner (EAC) attached to the furnace. As the indoor air circulates