Abstract: The present invention discloses a method and apparatus for sterilizing cartons with vapor-phase hydrogen peroxide and ultraviolet radiation on a packaging machine. A partially formed carton is first sprayed at a bottom forming station with a sterilant. Then, the carton is transported to a sterilization station where the carton is sprayed with gaseous hydrogen peroxide thereby allowing the gas to condense on the packaging material. The carton is then conveyed to a UV radiation source for irradiation of the packaging material. The carton is then dried with heated air to flush/remove any residual hydrogen peroxide. The present invention sterilizes the carton allowing for filling of the packaging material with a desired product such as milk, juice or water. The invention allows for the efficacious use of hydrogen peroxide having a concentration of up to 53% while providing a packaging material having less than 0.5 ppm hydrogen peroxide.