Abstract: The invention relates to an apparatus and a process for treating medical hazardous wastes to process them into waste similar to domestic refuse which can be removed or disposed of like normal domestic refuse or can be supplied for recycling after sorting. The infectious refuse is passed through a microwave chamber fitted with a plurality of microwave sources disposed next to each other and subjected to a disinfection therein. To achieve a safe and reliable treatment for decontaminating medical hazardous wastes in an economical and environmentally friendly manner, the apparatus has a two-stage construction of microwave chamber and temperature maintenance chamber. The microwave chamber has a dense microwave field distribution for heating the refuse to or above a selectable minimum temperature. Connected to the outlet of the microwave chamber is the temperature maintenance chamber which holds the refuse at at least the minimum temperature during a minimum residence time.