Wood pellets are a highly refined heating fuel, which is dried to a uniform 4-6% moisture content. The wood pellets are burned in well controlled systems that run extremely hot and with sufficient airflow to ensure complete combustion. As a result, pellets being burned annually in the United States, particulate emissions from the wood pellets only amount to <1% of the particulate emissions from forest fires and <2% of the emissions from less well controlled wood combustion.