Two sets of tests were carried out; in the first set, a series of six different experiments were conducted in which five different organic compounds diluted in heptane were burned in a water-jacketed, pilot-scale combustor. Excess air levels were varied to produce changes in the carbon monoxide (CO) concentration in the combustor exhaust. Tenax trap samples were taken at various CO levels for purposes of determining accompanying Destruction Efficiencies (DEs) and levels of Products of Incomplete Combustion (PICs). In the second set of tests, CO concentration was measured as a function of Swirl Number and nozzle position. During these tests, only an occasional measurement of DE was made. Overall results indicate that CO levels have only a tenuous relationship with DE and vary somewhat with the compound being burned; CO varies significantly with excess air and other combustion parameters.