HANDLING OF EXPOSED BIOLOGICAL INDICATORS

• PROCEDURE:
• BIOLOGICAL INDICATORS: In the context of sterilization, a biological indicator (BI) is a test system containing viable microorganisms with a defined resistance to a specific sterilization process. They are used to monitor the effectiveness of sterilization procedures, such as autoclaving or radiation sterilization. Because they are highly resistant to sterilization methods, their survival indicates that the process was not successful in killing all microorganisms. Conversely, if no BI organisms survive, it suggests the sterilization process was effective.

• Collect the exposed biological indicators in a sterilized container and transfer to the microbiology laboratory with intact condition.
• Bacillus stearothermophilus Strips Carries:
• Peel out the wrapper of exposed spore strips and aseptically inoculate the spore strips into 50 ml of soya bean casein digest medium tubes. Label the tubes for the identification.
• Similarly peel out wrapper of unexposed spore strips of same lot and inoculate the spore strips into 50 ml of Soya bean casein digest medium tubes and label the tubes as positive control.
• Incubate the exposed and unexposed spore strips medium tubes at 55-60 ℃ for 7 days.
• Observe the tubes every day and record the observation in the Exposed biological indicators recovery report as annexure-I.

• Acceptance criteria: No evidence of growth in the exposed spore strips medium tube. Luxuriant growth in the unexposed spore strips medium tube.
• Bacillus stearothermophilus self-contained spore suspension (Ampoule):
• Incubate the exposed self-contained spore suspension ampoule of the same lot at 55-60 0C for 7 days or Manufacture recommendation. Label the ampoules for identification.
• Similarly incubate the unexposed self-contained spore suspension ampoule of the same lot at 55-60 0C for 7 days or Manufacture recommendation. Label the tubes as positive control.
• Observe the ampoules every day and record the observation in the Exposed Biological Indicators recovery report in Format-I.
• Acceptance criteria: No evidence of growth and no colour change in the exposed spore suspension ampoule and luxuriant growth and colour change in the unexposed spore suspension ampoule.

• Bacillus subtilis Strips Carrier:
• Peel out the wrapper of exposed spore strips and aseptically inoculate the spore strips into 50ml of Soya bean casein digest medium tubes.
• Label the tubes for identification. Similarly peel out the wrapper of unexposed spore strips of same lot and inoculate the spore strips into 50 ml of soya bean casein digest medium tubes.
• Label the tubes as positive control. Incubate the exposed and unexposed spore strips medium tubes at 30-35 0C for 7 days.
• Observe the tubes every day and record the observation in the Exposed Biological Indicators recovery report as Format-I.
• Acceptance criteria: No evidence of growth in the exposed spore strips medium tube. Luxuriant growth in the unexposed spore strips medium tube.

• ANNEXURES: 

Annexure-I
Exposed Biological Indicators recovery report