The 2-fluoro-2,2-dichloroethoxy radical, CFCl2CH2O, is an intermediate in the mechanism of the tropospheric degradation of CFCl2CH3 (HCFC-141b), a chlorofluoromethane replacement in some large-scale industrial applications. In this work, the reaction of CFCl2CH2O with O-2 was investigated at 10-35 Torr and 251-341 K by UV flash photolysis and time-resolved mass spectrometry. CFCl2CH2O2 radicals were formed from the photolysis of CFCl2CH3/N-2/O-2 mixtures. The CFCl2CH2O radical is a product of the reactions of CFCl2CH2O2 with Cl and ClO and the self-reaction. The rate of formation and decay of CFCl2CH2O was followed by observations of the fragment ion CClCH2O+. The rate coefficient of the reaction of CFCl2CH2O with O-2, determined from CHCl2CH2O decay in excess O-2 by both pseudo-first-order analysis and nonlinear regression, can be expressed as (2.4 +/- 0.5 x 10(-15) exp[-944 +/- 55)/T] cm(3) molecule(-1) s(-1). The half-life for removal of CFCl2CH2O radicals from the atmosphere by the title reaction is 6 ms in the mid-troposphere and 1 s in the mid-stratosphere.