Steam autoclaving at 121 °C kills all bacteria including spores. To test the
temperature, use a standard holding thermometer. Autoclave tapes are heat sensitive
chemical indicators that change color after exposure to heat. They may be used to identify materials that have been processed through
the heating cycle, but do not ensure adequacy of a sterilization
cycle. Proper functioning of sterilization of the autoclave cycle
should be verified by the periodic use of biological indicators (i.e., spore test).
1. Place a glass ampoule of Bacillus stearothermophilus spores in the center
of a normal load.
2. Autoclave the load under normal operating procedures.
3. Incubate the ampoule according to manufacturer's instructions (usually
incubate at 56 °C for 48 hours).
4. If there is any change of color/appearance, the sterilization process
has failed. If no color change has occurred, the sterilization process