Process challenge device and sterilization system

A sterilization system comprising:

• a steam sterilizer comprising a sterilization chamber configured to receive a steam sterilant therein;
• and
• a process challenge device removably received within the sterilization chamber and configured to be used for determining the effectiveness of a sterilization procedure, the process challenge device comprising:
• a pouch comprising:
• an internal surface defining an internal storage space of the pouch;
• an external surface opposite to the internal surface;
• an inner film comprising at least 95% by weight of polypropylene (PP), the inner film comprising the internal surface;
• and
• an outer film attached to the inner film and comprising at least 95% by weight of polyethylene terephthalate (PET), wherein the outer film is disposed directly adjacent to and in contact with the inner film opposite to the internal surface, the outer film comprising the external surface;
• and
• a test indicator received within the internal storage space of the pouch;
• wherein:
• the pouch has a total thickness equal to a sum of a thickness of the inner film and a thickness of the outer film, the total thickness being greater than or equal to 62 microns and less than or equal to 65 microns;
• and
• the pouch has a water vapor transmission rate (WTVR) greater than 0.5 g/m2/24 hours and less than 3 g/m2/24 hours.