Abstract: A source of gas under pressure is interconnected by conduit means with at least one point of use through gas conditioning means which may include filter means and heater means and retention means specially arranged to maintain the temperature of a stream of gas for a desired period of time and a source of sterilizing fluid is interconnected with the conduit means and is arranged to scavenge the conduit means, the point of use and the gas conditioning means in coordination with the opening of vent means associated with the point of use, the gas conditioning means and the conduit means.