Steam is the oldest and most common sterilization process used in medical and related applications. Its proven effectiveness is further enhanced by being both reliable and economical. In this process, the item to be sterilized is placed in a chamber, e.g. an Autoclave. The item is exposed to a combination of heat and saturated steam (water vapor) for an established period of time. This process kills the micro-organisms present, sterilizing the item. Tempilinks are most commonly used in producing Type 1 and Type 2 (e.g. Bowie-Dick test packs) indicators. Tempilinks have also been used as elements to help create Type 4 and other types of chemical indicators.