By ARAcontent
Posted: Oct. 12, 2011 | 1:11 a.m.
Updated: Oct. 12, 2011 | 3:10 a.m.
When the winter winds start to howl, it’s a natural response to want to close your home up tightly. To stay warm and avoid wasting energy, you close the windows – or even seal them with window film — find ways to stop air from leaking in through cracks and under doors, and then put your heating system to work. But when those instincts kick in, remember that what you’re doing is sealing air inside your home.
There’s a definite upside to sealing your house up well for the winter: you’ll stay warmer, with less impact on your energy bills. However, the downside is that those actions can negatively affect the quality of the air you’ll be breathing. It’s a particular concern because of the increased amount of time people spend indoors through the winter.
Heating, ventilation and air conditioning (HVAC) systems have been shown to act as a collection source for a variety of contaminants that have the potential to affect health, such as mold, fungi, bacteria and very small particles of dust. According to the U.S. Environmental Protection Agency, indoor air can be two to five times more polluted than outdoor air.
“When you flip that switch on your heater, there is a lot of dust and debris – collected in the coils over the summer months – that either burns into fumes or gushes into the house through your vents,” says Aaron Marshbanks, board member of the National Air Duct Cleaners Association (NADCA).
• John P. Lapotaire, CIEC
• Certified Indoor Environmental Consultant
• Microshield Environmental Services, LLC
• www.Microshield-ES.com
Posted by John P. Lapotaire, CIEC 
Indoor Air Quality Solutions, IAQS 