What action should be taken if a biological indicator test fails?

If a biological indicator test fails, meaning that the Bacillus stearothermophilus spores survived the sterilization cycle, the first step is to immediately quarantine all items processed in that sterilizer load and prevent their use. This is because the sterilization process was not effective in killing microorganisms, and the items are considered non-sterile. The sterilizer should be taken out of service immediately. Next, a thorough investigation must be conducted to determine the cause of the failure. This includes reviewing the sterilizer's cycle parameters, such as temperature, pressure, and time, to identify any deviations from the established sterilization parameters. Check the sterilizer for mechanical malfunctions, such as leaks, faulty valves, or a malfunctioning vacuum system. Examine the biological indicator itself to ensure it was not expired or damaged and that it was properly incubated. Repeat the biological indicator test in three consecutive cycles, under a full load, to verify the initial failure wasn't an anomaly. If any of these repeat tests fail, more extensive repairs and revalidation of the sterilizer are required. All sterilization records should be reviewed for any trends or patterns that may indicate a recurring problem. The sterilizer should not be returned to service until the cause of the failure has been identified and corrected, and repeat biological indicator testing demonstrates consistent sterilization effectiveness.