Global flame properties were measured as a function of fuel mass flux in a series of experiments conducted on gaseous pool fires burning in a quiescent environment. The measurements included radiative heat loss, heat transfer to the burner, and sensible enthalpy transfer to the surroundings by convection. A large number of fires was studied encompassing a wide range of pool fire parameters. Measurements were conducted using methane, propane, natural gas, and acetylene in burners varying from 0.1 to 1 m in diameter, producing flames from 0.1 to 2 m in height with total heat release rates from 0.4 to 200 kW. From these measurements. the combustion efficiency was calculated for smoky fires. The measurements were used to test flame height correlations available in the literature for smoky fires. The correlations work well for nonsmoky fires but have not been proven for smoky fires. The measured flame heights conformed to the literature correlations for the nonsmoky flames burning methane, propane, and natural gas. When applied to high mass flux acetylene flames, however, the flame height measurements deviated from the literature flame height correlations. The correlations performed only slightly better when they were based on Qo the sensible enthalpy heat loss. Caution is suggested when applying the standard literature flame-height correlations to smoky firestthat may occur in realistic fire scenarios.