Chimney sweeps are for integrity purposes, cleaning, and obstruction free assurance. Creosote, also known as soot, is a natural byproduct of burning wood. As the smoke goes up your fireplace chimney, creosote clings to the inner walls of your chimney. Creosote is highly flammable and causes chimney fires. An annually chimney sweep with inspection helps to provide safe continuous use as recommended by Code 211 of the NFPA (National Fire Protection Association).