An apparatus (10) and a method for sterilization of a web (12) of packaging material are provided. The apparatus comprises a bath (20) through which the web is to be passed and a transfer system for transferring sterilization fluid from a supply (30) of sterilization fluid to the bath. The apparatus is characterized in that the transfer system comprises a buffer tank (18) to which sterilization fluid is transferred from the supply and a movable volume regulating element (34) for transferring sterilization fluid from the buffer tank to the bath. At least a part (36) of the volume regulating element is arranged to be received in the buffer tank and act upon the sterilization fluid therein, a volume of sterilization fluid in the bath thereby being a function of a position of the volume regulating element in the buffer tank. To be published with figure 2
