Hydrogen Peroxide Monitoring
Hydrogen peroxide monitoring in the STERRAD NX® Sterilizer and STERRAD® 100NX Sterilizer ensures concentration levels of hydrogen peroxide are maintained during the exposure period for effective microbicidal activity. The STERRAD NX® Sterilizer and STERRAD® 100NX Sterilizer feature a control system with a fully integrated hydrogen peroxide monitor as a standard equipment for direct measurement of the chamber sterilant concentration. The hydrogen peroxide monitor provides data to the process controller which uses this data and information on acceptable cycle limits determined by statistical analysis of microbiological efficacy testing to make decisions regarding the acceptability of each cycle and ensure a minimum sterility assurance level (SAL) of 10-6.
STERRAD® System’s built-in continuous hydrogen peroxide monitor consists of a UV light source and detector that senses fluctuations in the interaction between the hydrogen peroxide vapor and UV light intensity. When the concentration of hydrogen peroxide drops below a defined threshold for sterilization, the UV light intensity changes, signaling the system to abort the sterilization cycle.
Gas Plasma
STERRAD® Systems, also referred to as Vaporized Hydrogen Peroxide Gas Plasma Sterilization, utilize an exclusive gas plasma technology to directly remove hydrogen peroxide residual from the chamber and instruments. Once hydrogen peroxide diffuses through the chamber and surrounds the instrument in the load, the low-temperature gas plasma is ignited by applying an electric field. Plasma causes the hydrogen peroxide vapor to break apart into free radicals. When plasma energy is terminated, the free radicals lose their high energy state and recombine as oxygen and water vapor.

STERRAD® Systems minimize healthcare worker exposure to hydrogen peroxide when opening the sterilizer door after a completed cycle and emits significantly less hydrogen peroxide than STERIS® VPRO-Sterilizers.
In a side-by-side comparative study2, continuous hydrogen peroxide emissions monitoring of STERRAD® Systems and STERIS® V-PRO® Sterilizers resulted with V-PRO® Sterilizers emissions registering 67 times higher than those of STERRAD® Systems when opening the sterilizer door after a cycle. The results of the study demonstrate that STERRAD® Systems which uses a gas plasma phase to dissociate hydrogen peroxide during the sterilization cycle, is more effective in limiting hydrogen peroxides than the STERIS® V-PRO® maX, which only passes hydrogen peroxide through a catalytic converter.