How is the effectiveness of an Autoclave/Sterilizer tested?
There are physical, chemical, and biological indicators that can be used to ensure an autoclave reaches the correct temperature for the correct amount of time. Chemical indicators can be found on medical packaging and autoclave tape, and these change color once the correct conditions have been met. This color change indicates that the object inside the package, or under the tape, has been autoclaved sufficiently. Biological indicators include Attest devices. These contain spores of a heat-resistant bacterium. If the autoclave does not reach the right temperature, the spores will germinate, and their metabolism will change the color of a pH-sensitive chemical. Physical indicators often consist of an alloy designed to melt only after being subjected to 121 C for 15 minutes. If the alloy melts, the change will be visible. In addition to these indicators, autoclaves have temperature and pressure gauges that can be viewed from the outside.
