EPA isn't going to suggest which the air ducts be cleaned routinely, but only as necessary. EPA does, however, advocate that When you have a gasoline burning furnace, stove or fireplace, they be inspected for appropriate functioning and serviced ahead of Every heating time to guard versus carbon monoxide poisoning. https://kylerayvtm.celticwiki.com/1242523/considerations_to_know_about_duct_cleaning