Performance evaluation of chemical, biological and physical indicators in the process of sterilization under the effect of non-condensable gases

The risk concerning the presence of non-condensable gases (NCGs) has already been demonstrated, but routine monitoring still requires further research to be implemented in each sterilization cycle. Performance evaluation of the physical, chemical and biological indicators used in monitoring in comparison with a sterilizer integrated detector for NCG in the Sterilization Process. Chemical indicators (type 2 Bowie–Dick test, type 5 and type 6 models), self-contained biological indicators and physical indicators (temperature, pressure, thermal qualification and a patented integrated air detector) were used to monitor the steam sterilization process in two situations of controlled failure: chamber leakage and door seal failure. This controlled failure was obtained by the presence of a known amount of air: 0–30 L/min for chamber leakage and 0–30% for the door seal failure. Evaluation tests were carried out with and without the use of process challenge devices (PCDs). In both studies, the Bowie-Dick Test showed different results, according to the manufacturer. The biological, physical or chemical indicators without a PCD were unable to detect small volumes of NCGs in both simulations. The integrated air detector can be considered an option for the detection of NCGs in each cycle.