Shop STERIS Online Account 
Select Your Region
Biological indicators (BIs) provide information on whether necessary conditions were met to kill a specified number of microorganisms (bacterial spores) for a given sterilization process. STERIS's complete portfolio of biological indicators offers testing for various applications, including steam sterilization and vaporized hydrogen peroxide (VH2O2) sterilization. Geobacillus stearothermophilus spores are mainly used in these applications due to their high resistance to these sterilization processes.
BIs are typically used within process challenge devices (PCD), designed to represent the most challenging products routinely processed for sterilization testing. A passing result for the BI within the PCD demonstrates that the sterilization cycle effectively inactivates the BI, providing Sterile Processing Department staff with assurance in their steam or VH2O2 sterilization process.
STERIS biological indicators for steam sterilization include self-contained biological indicators (SCBI) and process challenge devices or test packs. These devices play a crucial role in sterility assurance and provide the only direct measure of the lethality of the sterilization process. Browse steam sterilization biological indicators by read times, compatible autoclave cycles, and key features and benefits.
Browse STERIS biological indicators for use in V-PRO™ Low Temperature Sterilization Systems or STERRAD™ Models. Single-use biological indicators help monitor vaporized hydrogen peroxide (VH2O2) sterilization processes, while challenge packs are used during qualification testing of V-PRO sterilizers. With the Celerity HP Biological Indicator, you can get BI results in as little as 5 minutes!
Incubators play a crucial role in the sterility assurance process by testing if all viable organisms in the biological indicator test vial have been eliminated. The incubator heats the activated BIs to temperatures that promote the metabolism and subsequent detection of viable test organisms under evaluation.
In most modern incubators, while the activated BI is incubating, viability is determined by an increase in a fluorescent signal from the enzymatic breakdown of a fluorogenic substrate in the media. Once initiated, each well independently monitors the potential fluorescence generated from the activity of α-glucosidase within the BI. Detection of a fluorogenic substrate following catalysis by α-glucosidase indicates a positive response, while the absence of fluorescence produces a negative result. A negative result indicates that all viable organisms in the test vial have been eliminated. Modern incubators will show the results to the user audibly and visually within each BI's validated readout time.
* STERRAD™ is the registered trademark of Advanced Sterilization Products.
