The Minidox-M chlorine dioxide gas sterilization system provides a rapid and highly effective method to decontaminate isolators, rooms, processing equipment, and pass-throughs as well as to sterilize products or components. The Minidox-M offers a sophisticated, fully integrated, sterilant concentration monitoring system, which provides precise monitoring and control of gas concentration. This creates a very repeatable and tightly controlled decontamination process that is easier to validate. By using a true gas, the system benefits include a more efficacious cycle due to better distribution into hard to reach areas, no concern for condensation or temperature gradients, and much quicker aeration.