How Wood Burns

If you take a close look at a burning log, you will notice something strange. In most instances, fire appears only over a portion of the log. At the same time, smoke is coming off, usually from a part of the log remote from the flame itself. This smoke is composed of a complex mix of volatile incomplete combustion products that are being "boiled" or distilled out of the wood before they can be burned. Without a means of igniting these products and further burning them before they leave the combustion chamber, these incomplete combustion products become creosote which can cause chimney fires, and also turn into "particulates," which can be a major source of air pollution as well as indoor air quality problems.