What is the purpose of the Biological Indicator in sterilization processes?

The purpose of the Biological Indicator in sterilization processes is to confirm the presence of living microorganisms. Biological indicators are specifically designed to provide an unequivocal measure of the effectiveness of the sterilization cycle by using a known organism that is resistant to the sterilization process being tested. For example, spores of Bacillus stearothermophilus are commonly used for steam sterilization, while spores of Bacillus subtilis might be used for dry heat or ethylene oxide sterilization.

When the sterilization process is carried out, the biological indicator is exposed to the same conditions as the items being sterilized. After the cycle, the biological indicator is incubated, and if there is growth, it indicates that the sterilization process was insufficient to destroy these resistant microorganisms. A lack of growth confirms that the conditions within the sterilizer were adequate to achieve sterilization.

This critical function makes biological indicators a cornerstone in sterilization monitoring, ensuring the process is effective in eliminating all forms of viable microorganisms, thereby safeguarding patient safety and compliance with health standards. Other options, while important in various contexts related to sterilization and instrument processing, do not directly serve the primary confirmation role that biological indicators fulfill in validating the sterilization process.