The ability of the Noxilizer sterilization process to sterilize rigid and flexible lumens was compared to the ASP STERRAD 100NX hydrogen peroxide process. For this test, three different lumen geometries were used. These were: stainless steel, 300 mm long and 2 mm diameter; stainless steel, 500 mm long and 2 mm diameter; and, Teflon, 4000 mm long and 1 mm diameter. Lumens were inoculated with more than 106 spores of Geobacillus stearothermophilus prior to exposure to the sterilization processes. The NO2 processed lumens were treated in a prototype hospital sterilizer, called the ARTS unit. The lumens processed by hydrogen peroxide were taken to a hospital for processing in a STERRAD 100 NX system. The results show that, for rigid and flexible lumens, the Noxilizer cycle (with the cycle parameters chosen) was at least equivalent to the H2O2 cycle in the STERRAD 100 NX.