Biological Indicators Types

Biological Indicators Types

1. By Structure:
   • Strip Biological Indicators: Require both positive and negative controls for validation.
   • Self-Contained Biological Indicators: Require only a positive control, simplifying the process.
2. By ISO 11138-1 (2006) Classification: Biological indicators are categorized based on the sterilization method they monitor:
   • Ethylene Oxide (EO) Sterilization Biological Indicators
   • Moist Heat Sterilization Biological Indicators
   • Dry Heat Sterilization Biological Indicators
   • Low-Temperature Hydrogen Peroxide Plasma Sterilization Biological Indicators
   • Formaldehyde Sterilization Biological Indicators
3. By Incubation Time:
   • Standard Biological Indicators:
     • Detect changes in pH levels caused by microbial metabolism after spore recovery.
     • Utilize acid-base indicators for color change interpretation.
     • Require 24 to 48 hours or more for results.
   • Rapid Biological Indicators:
     • Detect enzymatic activity via fluorescence after spore recovery.
     • Provide results within 3-4 hours.
     • Advanced rapid biological indicators are currently in development internationally, with potential for results in under 1 hour.