Abstract The rate constants of the reactions between the OH radical and a series of hydrofluoroethers (HFE) have been measured. The reaction of OH with CHF 2 OCF 2 OCHF 2 (1), CHF 2 OCF 2 CF 2 OCHF 2 (2), CHF 2 OCF 2 CF 2 OCF 2 OCHF 2 (3) and CH 3 OC 4 F 9 (4) were investigated at 295±3 K and 740±5 Torr total pressure. The following values of the rate constants were determined for the reaction with the OH radical: k 1 =(2.4±0.7)×10 -15 cm 3 molecule -1 s -1 , k 2 =(4.7±1.6)×10 -15 cm 3 molecule -1 s -1 , k 3 =(4.6±1.6)×10 -15 cm 3 molecule -1 s -1 and k 4 =(7.2±1.6)×10 -15 cm 3 molecule -1 s -1 . (All values are given with 2 σ uncertainties). Infrared spectra were obtained for all four HFEs in the range from 600 to 4000 cm -1 (3 to 17 μm), with the following IBI-values (integrated band intensities): IBI 1 = (5.19±0.23)×10 -16 cm molecule -1 for the 978–1584 cm -1 band, IBI 2 =(6.04±0.13)×10 -16 cm molecule -1 for the 930–1501 cm -1 band, IBI 3 =(8.49±0.34)×10 -16 cm molecule -1 from the 963–1587 cm -1 band and IBI 4 =(4.23±0.14)×10 -16 cm molecule -1 for the 845–1428 cm -1 band. Carbonyl fluoride, CF 2 O, was the only fluorine-containing degradation product that was found from the Cl atom-initiated reactions of both CHF 2 OCF 2 OCF 2 CF 2 OCHF 2 and CH 3 OC 4 F 9 , with measured product yields of 60–97% and 20–40% (based on carbon atoms), respectively. Due to the high uptake parameter of CF 2 O to liquid water, its lifetime in the atmosphere is very short (with an upper limit between 15 and 30 d). It is rapidly incorporated into raindrops/aerosols, where it eventually degrades to HF and CO 2 . The GWP of CF 2 O is therefore negligible compared to those of CFC-11 and CFC-12.