Sterilization (microbiology) equal to the probability of a non-sterile unit. For high-risk applications, such as medical devices and injections, a sterility assurance level of at least 10 is required by the United States Food and Drug Administration (FDA). A widely used method for heat sterilization is the autoclave, sometimes called a converter or steam sterilizer. Autoclaves use steam heated to under pressure. To achieve sterility, the article is placed in a chamber and heated by injected steam until the article reaches a temperature and time setpoint. Almost all the air is removed from the chamber, because air is undesired in the moist
Rail fastening system spring steel clips that attach to the underside of the rail baseplate and bear against the sides of the sleepers to prevent longitudinal movement of the rail, either from changes in temperature or through vibration. Rail fastening system A rail fastening system is a means of fixing rails to railroad ties (North America) or sleepers (British Isles, Australasia, and Africa). The terms "rail anchors", "tie plates", "chairs" and "track fasteners" are used to refer to parts or all of a rail fastening system. Various types of fastening have been used over the years. The earliest wooden rails were fixed to