Furnace out emissions of benzene, toluene, and formaldehyde during the combustion of wood were measured using a well-controlled plug flow research combustor which simulates an updraft fixed grate combustor. The woods examined were southern pine, southern pine plywood, and southern pine particleboard. The range of conditions for combustion were residence times between 0.5 and 3.0 s, exit temperatures between 300 and 950 °C, equivalence ratios ((fuel/air)act/(fuel/air)stoic) between 0.1 and 0.3. For residence time of 1 s, benzene, toluene, and formaldehyde emissions were very low to undetected at exit temperatures above 650 °C, but at temperatures less 650 °C emissions increased to as high as 2 ppmv for benzene, 0.4 ppmv for toluene, and 40 ppmv for formaldehyde. Furnace out emissions and emission factors were correlated to CO concentration. For plywood the CO had to increase to 4000 ppmv (corrected to 7% O2) before emission levels increased rapidly, and for pine the CO had to increase to 2000 ppmv (corrected to 7% O2) before emission levels increased rapidly.