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

Abstract

Background: 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.

Aim: 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.

Methods: 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).

Findings: 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.

Conclusion: The integrated air detector can be considered an option for the detection of NCGs in each cycle.

Keywords: Air detector; Monitoring; Non-condensable gases; Steam; Sterilization.