Which method of monitoring the effectiveness of sanitation or sterilization uses spores in a vial?

• A. Microbial swaps
• B. Biological indicators
• C. RODAC plates
• D. Bioluminescence monitoring systems

Answer: (B)

Biological indicators use spores in a sealed vial to challenge the sterilization process. The vial contains highly resistant bacterial spores and a growth medium. After a sterilization cycle, the indicator is incubated; if the spores germinate and grow, the cycle did not achieve the necessary kill. If there is no growth, the process met the required sterilization criteria. Because spores represent a worst-case scenario, biological indicators provide direct evidence that the sterilization step is effective.

Other options are used for different quality checks. Microbial swabs and RODAC plates sample surfaces to assess surface cleanliness or bioburden rather than proving the load was sterilized. Bioluminescence systems measure ATP to gauge organic residue and cleanliness, but they do not directly confirm sterilization efficacy.