With increased use of highly fluorinated compounds has come an increased need for knowledge of the fundamental properties of these chemicals, such as vapor pressure, to determine how they will behave in the environment and how to remove them. A modified vapor saturation method was used to measure the ambient temperature vapor pressure of 3-(perfluorobutyl)propanol, (perfluorooctyl)ethylene, perfluorohexanoic acid, ethyl perfluorooctanoate, and perfluoro-3,6-dioxaheptanoic acid between (254.15 and 309.15) K. The freezing point for perfluorohexanoic acid was determined to be between (291.15 and 293.15) K The vapor pressures, which ranged from (0.87 to 978) Pa, were used to generate saturated vapor streams of the compound so that adsorption capacities on BPL activated carbon could be determined. Adsorption equilibrium data for three of the chemicals, measured at a feed concentration of 139 mu L.L-1 at high and low relative humidity, are presented and discussed.