Biological Indicator (BI)
The most reliable method of verifying the sterilization effectiveness of autoclaves. These small vials require a specific incubation period and protocol after which they are read or interpreted through observation of the vial's liquid media contents. Observations are most frequently based on a color change or change in turbidity (cloudiness). Examples include Magna Amps for liquid cycles and Steris Verify for gravity/prevac cycles.