Almost every fireplace tested in accordance with the Washington State fireplace standard, designed to be "equivalent" to the EPA Phase II stove standard, passed. Some fireplaces, like Rumfords and Rosins, tested two or three times cleaner than the stove standard. (See Rumford Test Results.)
So, why do so many people think fireplaces are dirty and inefficient?
It all began nearly thirty years ago when the American Lung Association tried to get the EPA to regulate the air-tight European stoves that flooded the US market during the energy crisis of the late 1970's and early 1980's. Americans didn't know how to use the stoves and allowed them to smolder as they bragged to their friends how long they could bank a fire. The Lung Association eventually had to sue the EPA which did not want to get into regulating on a retail basis. It was easier to regulate industry than to dictate what people could do in their own homes.
The suit brought against EPA resulted in a very narrowly drawn "smoldering stove" standard. Fireplaces, masonry heaters and other "inherently" clean-burning appliances were exempted. See details)
The American stove industry and their association, the Hearth, Patio & Barbecue Association, grew up developing stoves that would pass the EPA emissions standards - and, while they were at it, keep the European stoves out of the US market and buy up or put out of business all the small US stove manufacturers.
After thirty years of testing and marketing American stoves, is it any wonder that most of the scientists who do the testing and most of the people who write the articles and research papers work for or are paid by the stove manufactures? Not that they were not objective, especially the scientists running certified independent test labs, but they all had an interest in showing how clean the new and improved American stoves were compared with the bad old stoves and fireplaces. ( For example see Skip Hayden's anti fireplace article.)
People who liked and understood fireplaces were not the ones testing fireplaces. Rather it was people who had an interest in showing how bad fireplaces were and how good stoves were who tested fireplaces. How could that be? Does General Motors hire Ford to do marketing? Why didn't the masonry industry take an interest? Suffice it to say fireplaces were "exempt" and the masonry industry, organized like a farmers cooperative, wasn't focused. Who should take responsibility for masonry fireplaces? Masons? Brick and block manufacturers? Flue liner or firebrick manufacturers? Independent dealers who sell the materials? Well none of us took responsibility. We were all out to lunch. We just watched masonry fireplaces denigrated and our markets slip away.
Some fireplaces, like Rumfords and Rosins, have tested as clean or cleaner than EPA certified stoves. With more testing, fair standards and more time, we will find even more improvement. What we need are clear objective performance standards and rules that allow fireplaces that meet the same performance standards that the stoves that are allowed meet. We are now working on an ASTM national consensus fireplace emissions standard that EPA will recognize.
For much more information about fireplace testing and the politics of fireplace certification, see Rumford's article on Emissions.