Description Wood is an important renewable source of fuel for residential heat, with 10% of American households (approximately 13 million) burning wood for heat and 2% using wood as their primary heat source. Although wood heaters provide a small percentage of energy used in residences in the United States, the devices are a substantial source of particulate matter emissions. These emissions contain fine particulate matter (PM) along with other pollutants, including carbon monoxide (CO), volatile organic compounds...