Steam sterilization chemical indicators are not adequate for monitoring real steam sterilization cycles.

Chemical indicators are commonly used in hospitals to monitor steam sterilization conditions, indicating that medical devices are safe to be used. The results are stored for future evidence in the event of an infection incident root cause analysis. This type of indicator is also becoming an option for cycle monitoring in pharmaceutical steam sterilizers, improving cycle control. They are constructed and tested according to published standards, but contradictory results between chemical indicators and cycle printouts have a critical impact on process control. We found that type 6 chemical indicators used in steam sterilizer cycles did not perform according to their intended use, showing an ″approved″ result in a ″failed″ cycle (a false positive). This study demonstrated that type 6 chemical indicator specifications are not adequate for monitoring steam sterilizers. A change in standards is therefore needed.