Abstract: The invention relates to radiation engineering. The inventive method for irradiating objects consists in generating the pulsed ionising radiation and exposing objects to the effect thereof. Said irradiation is carried out by an electron beam or X-rays such that said objects are subjected to the radiation treatment and sterilised. A type of radiation, treatment mode and irradiation field are selected using a set of replaceable sealed-off electron or X-ray tubes. The irradiation field is generated by one or more modules and by spatial handling of modules with respect to an irradiated object. The inventive method is carried out with a device for irradiating an object, comprising a power supply unit, control unit and high-voltage unit provided with a sealed-off electron or X-ray tube. The device further comprises a set of replaceable sealed-off electron and/or X-ray tubes and at least one module consisting of the high-voltage unit and a sealed-off electron and/or X-ray tube selected from the set.