Towards a multi-sensor system for the evaluation of aseptic processes employing hydrogen peroxide vapour (H2O2)

The presented work focuses on the development of a multi‐sensor system for the evaluation of aseptic processes employing hydrogen peroxide vapour. In a first step, selected commercially available gas sensors have been investigated on cross‐sensitivity towards hydrogen peroxide vapour and humidity. An MOX (TGS 816, Figaro) and a solid‐electrolyte gas sensor (SO‐A0‐250, Electrovac) (λ‐probe) have shown good characteristics in terms of sensitivity towards HPV, considering also reproducibility, long‐term drift and stability. Further, the sterilization effect of HPV has been investigated by means of the microbial reduction test. A correlation between the microbial reduction of Bacillus subtilis spores and the sensor response in hydrogen peroxide atmosphere has been established. Based on this correlation the microbial reduction may be estimated by means of the sensor output over a wide range of parameters.