The report describes an exploratory study of factors contributing to atmospheric emissions from residential wood-fired combustion equipment. Three commercial appliances were operated with both normal and modified designs, providing different burning modes: updraft with a grate, updraft with a hearth, crossdraft, downdraft, and a high-turbulence mode utilizing a forced-draft blower. Fuels were naturally dried commercial oak cordwood, commercial green pine cordwood, oven-dried fir brands, and naturally dried oak cut into reproducible triangles. Continuous measurements of stack gases included O2, CO2, CO, NO, SO2, and total hydrocarbons (FID) as an indication of the total organic species in the stack gases during batch type operation. Several combustion modification techniques were identified which have an appreciable effect on emission factors and, therefore, can be developed and applied to reduce emissions in consumer use. The more promising design modifications include: prevention of heating the inventory of wood within the stove but not yet actively burning, focusing the air supply into the primary burning area with high turbulence, and increasing the temperatures in the secondary burning regions of the appliances.