an apparatus for shaping plastic preforms for providing plastic containers ), having a plurality of shaping stations arranged on a movable carrier , wherein the shaping stations have blowing moulds which accommodate the preforms and within which the preforms are shaped to provide the containers , and wherein the shaping stations each have charging devices which are movable relative to the preforms and which charge the preforms arranged in the moulds with a flowable medium for expansion , and wherein the shaping stations have a valve arrangement which controls the feed of the medium to the preforms , with a clean chamber within which the shaping stations are conveyed with the charging devices , wherein the clean chamber is arranged against the surroundings by at least one wall . flow connections for guiding the flowable medium are provided between the valve arrangements and the charging devices and the valve arrangements are arranged outside the clean chamber .