A method of sterilizing packaging means (10) and, in particular, plastics material pre-forms (10), wherein the packaging means (10) are conveyed with a conveying device (2) and wherein at least one area of the packaging means (10) is acted upon with a flowable medium by a stressing device (4). According to the invention the medium applied to the area is subjected to irradiation with electromagnetic radiation in order to produce singlet oxygen, wherein this singlet oxygen is used to sterilize the packaging means (10).
