The photooxidation of tribromofluoromethane isolated in an ozone/argon matrix and in an oxygen matrix has been studied by FTIR spectroscopy. Photolysis of CBr3F with ultraviolet radiation (lambda > 240 nm) in these matrices leads to the formation of carbonyl bromide fluoride, COBrF, and bromine. Further irradiation in the visible (lambda > 350 nm) leads to the rupture of the C-Br bond of COBrF and the formation of the fluorocarbonyl radical, FCO, and bromine atoms. COBrF is reformed on heating the matrix. It is believed that the peroxide FC(O)O-2 has been detected, this being formed when the FCO radical combines with O-2. The FCO radicals can also combine with themselves to form COF2, which has been detected here, in the form of a COF2...Br2 complex. The photooxidation of CBr3F in solid oxygen is also reported; this matrix appears to stabilize the peroxide. The products have been identified using time- and wavelength-dependent photolysis and heating. Separate experiments were conducted using O-18(3) in place of ozone of normal isotopic distribution, in order to assist in making the band assignments.