A pulse radiolysis technique was used to study the UV absorption spectrum of CF₃CF₂CF₂O₂ radicals, at 230 nm σ = (3.2 ± 0.4) × 10^-18 cm² molecule^-1. Rate constants for reactions of CF₃CF₂CF₂O₂ radicals with NO and NO₂ were k₃ > 7 × 10^-12 cm³ molecule^-1 s^-1 and k₄ = (7.6 ± 2.4) × 10^-12 cm³ molecule^-1 s^-1, respectively. The rate constant for reaction of F atoms with CF₃CF₂CF₂H was determined by using an absolute rate technique to be (3.6 ± 1.3) × 10^-13 cm³ molecule^-1 s^-1. The atmospheric fate of CF₃CF₂CF₂O radicals is decomposition via C-C bond scission to give CF₃CF₂ radicals and CF₂O. In one bar of SF₆ at 296 K, CF₃CF₂CF₂O radicals decompose with a rate > 1.5 × 10⁵ s^-1. In their turn CF₃CF₂ radicals are converted into CF₃CF₂O radicals which also decompose via C-C bond scission. As part of this work a relative rate method was used to measure k(Cl + CF₃CF₂CF₂H) = (3.4 ± 0.7) × 10^-16 and k(F + CF₃CF₂CF₂H) = (3.2 ± 0.8) × 10^-13 cm³ molecule^-1 s^-1. The results are discussed with respect to the atmospheric chemistry of HFC-227ca.