We have an old Fisher airtight wood stove that has heated our home for nearly 20 years. Our new neighbors have complained about our smoke, and are threatening to call the EPA and get us busted. But that doesn't necessarily mean you're off the hook with your neighbors.
Many States have their own air quality regulations for existing woodstove installations.
If your neighbors ever decided to sic the smoke cops on you, it would be your State EPA they would call in, not the Feds. Opacity tests show how much light is obscured by smoke or other particulates in the air. A clear pane of glass would register zero percent opacity, while a brick wall would score 100 percent. I know you probably love your old Fisher, which has heated your house for two decades and undoubtedly paid for itself many times over in fuel savings, but you must prepare yourself for the likelihood that it won't pass the opacity test. Your Fisher, all by itself, spews out more airborne particulates than twenty EPA approved woodstoves.