Abstract: A method monitors the concentration of an oxidative gas or vapor during a sterilization process in a sterilization chamber. A sensor formed of a chemical reactive with the oxidative gas or vapor coupled to a temperature probe is positioned inside of an enclosure containing an item to be sterilized. The enclosure is defined by a barrier impermeable to contaminating microorganisms and having at least a portion thereof which is permeable to the oxidative gas or vapor. The sensor is electrically connected through the barrier to contacts located exterior of the enclosure and connected to a control system thereby.

Abstract: An apparatus for monitoring the concentration of an oxidative gas or vapor includes a first thermocouple junction and a chemical substance coupled to the first thermocouple junction. The chemical substance is reactive with the oxidative gas or vapor to produce heat. The apparatus further includes a second thermocouple junction coupled in series to the first thermocouple junction. A net voltage is generated across the first and second thermocouple junctions upon exposure of the chemical substance to the oxidative gas or vapor. The net voltage corresponds to the concentration of the oxidative gas or vapor.

Abstract: A method monitors a concentration of an oxidative gas or vapor in a diffusion-restricted region in fluid communication with a sterilization chamber during a sterilization process. The method includes providing a concentration monitor responsive to the oxidative gas or vapor by generating a parameter corresponding to the concentration of the oxidative gas or vapor. The concentration monitor includes a temperature sensing device coupled to a chemical substance reactive with the oxidative gas or vapor to produce heat. The method further includes placing at least a portion of the concentration monitor comprising the chemical substance within the diffusion-restricted region. The method further includes introducing the oxidative gas or vapor into the sterilization chamber. The method further includes monitoring the parameter generated by the concentration monitor during the sterilization process.