Hydrogen Peroxide Sterilization 

Hydrogen peroxide acts as a strong oxidizing agent, breaking down cell walls and disrupting the DNA of microorganisms, making it ideal for sterilization across a wide range of applications. In vaporized form, H₂O₂ penetrates small cavities and complex geometries, which is particularly suited for intricate medical devices. By ionizing hydrogen peroxide vapor, a plasma is generated that forms highly reactive free radicals, effectively killing bacteria, viruses, and spores.

ISO 22441 defines the general requirements for H₂O₂ sterilization process control, including timing, temperature, gas concentration, and vacuum pressure levels.

Vacuum Measurement and Control in H₂O₂ Sterilization Equipment

During the hydrogen peroxide plasma sterilization process, the process chamber is maintained under vacuum pressure. The vacuum pressure lowers the boiling point of H₂O₂, enabling the sterilization process to occur at a low temperature. Additionally, the vacuum provides the conditions necessary to sustain a stable plasma.

The VDM-5 DiCAP™ vacuum transducer is a multi-sensor solution for measuring and controlling vacuum pressure during the hydrogen peroxide sterilization process. The highly reactive nature of hydrogen peroxide free radicals, such as hydroxyl and superoxide ions, sets special requirements for robust vacuum pressure measurement. To meet this demanding requirement, Sens4 has developed an advanced conformal Parylene coating for its diaphragm sensors. Parylene is a unique polymer that has been used in the medical industry for decades to coat medical instrument surfaces.

Combine multiple Vacuum Sensors

Multiple vacuum gauges have traditionally been used in hydrogen peroxide sterilization equipment to cover the dynamic pressure range from atmospheric pressure down to approximately 1E-2 mbar. The typical plasma sterilization process pressure takes place in the range 0.5 to 5 mbar.  

The new VDM-5 DiCAP™ transducer offers a cost-effective, gas-independent, all-in-one, and reliable pressure measurement solution for hydrogen peroxide sterilization equipment. Additionally accurate control of ventilation to atmospheric pressure can be utilized with the VDM-7 DiCAP™ ATM that also included atmospheric switching function.