Emissions from two biofuels, a soy-based biodiesel and an animal-based biodiesel, were measured and compared to emissions from a distillate petroleum fuel oil. The three fuels were burned in a small (3.5x10 Btu/hr) firetube boiler designed for use in institutional, commercial, and light industrial applications. Emissions were measured for carbon monoxide (CO), carbon dioxide (CO2), oxides of ni...