A fluid tight waste materials receptacle is located within a housing which has an upper access opening through which infectious wastes from medical clinics or the like may be deposited in the receptacle. A lower access opening enables entry and withdrawal of a sterilized waste receiver which may, for example, be a wheeled cart. The receptacle has an open end and a closed end and is pivotable between a first orientation at which the open end is coincident with the upper access opening in order to receive wastes and a second orientation at which the open end is turned downward to discharge wastes into the receiver. A closure pivoted to the housing seats in and seals the open end of the receptacle when it is at the first orientation. The receptacle is periodically evacuated and steam is admitted to sterilize the contents prior to discharge into the receiver.