The truth is that the jury is still out on duct cleaning. As the EPA points out, “Duct cleaning has never been shown to actually prevent health problems. Neither do studies conclusively demonstrate that particle (e.g., dust) levels in homes increase because of dirty air ducts.”

Why? Most of the dust in the air will stick to the duct surface and not necessarily get into the living space. That said, however, breathing problems can be caused by any number of pollutants. “Pollutants that enter the home both from outdoors and indoor activities such as cooking, cleaning, smoking, or just moving around can cause greater exposure to contaminants than dirty air ducts,” the EPA states on its website.

When Duct Cleaning is Needed

However, the EPA does recommend duct cleaning if there is substantial mold growth on your ducts or within your heating system. They also recommend cleaning if your ducts are infested with vermin, such as bugs or rodents.