Regularly cleaning your fireplace can reduce dust and particulates in the air, lessen smoky odors, and reduce the chance of accidental fire damage.  The National Fire Protection Association recommends that both your chimney and fireplace be inspected for soundness and cleaned annually, since buildup of creosote can cause fires to flare out of control.  A dirty fireplace can also mean the fire is inefficient, and a build-up of creosote is a hazard.  Cleaning your chimney flue will allow the necessary ventilation while burning wood by allowing the smooth passage of carbon dioxide emanating from the fire fuel, and will eliminate the risks of house fires.  Even gas-powered fireplaces should be cleaned regularly