Rate constants for the reactions of OH radicals with CH₃CHF₂ and CHC1₂CF₃ have been determined overthe temperature range 295-388 K and a total pressure of 1 atm. The OH rate data were obtained using the absolute rate technique of pulse radiolysis combined with kinetic spectroscopy. The data can be fit to the Arrhenius expressions: k_OH+HFC-152a=3.9 × 10^-12 exp[(-1370±260)/T] cm³ molecule^-1s^-1 and k_OH+HCF-123=1.1 × 10^-12 × exp[(-940±200/T] cm³ molecule^-1s^-1. The results are compared to the available literature data and discussed in terms of reactivity trends and in the light of the important role CH₃CHF₂ and CHCl₂CF₃ play as alternatives to the fully halogenated chlorofluorocarbons.