Wound therapy device and method

A wound therapy device, comprising:

• a skin contacting element configured for covering an associated tissue site, the skin contacting element having a skin contacting side and an interface side, which is opposite the skin contacting side;
• a reactor for creating a pressure condition at the associated tissue site upon actuation thereof;
• and
• a reactor housing element for accommodating the reactor, the reactor housing element having a lower affixing side and an upper side, which is opposite the lower affixing side;
• and
• a package including at least one air-tight barrier selectively removable from the package, wherein the reactor is positioned within the package and a selected gas found in air is precluded from access to the reactor until after the at least one air-tight barrier is removed from the package.