What does our indoor air quality testing in Walker, MI look for? Not so much pollution from nearby cities, just normal, everyday airborne substances generated at home. Modern homes are carefully sealed for energy savings, and your air circulates to keep everyone comfortable. There’s a lot in that air that we’re breathing without realizing it. The EPA has a list of the more significant concerns, and our Bel-Aire Heating & Cooling indoor air quality or IAQ team can identify them in your home’s air.