A device for forming plastic preforms into plastic containers with a mobile carrier on which is arranged a plurality of blowing stations, each comprising blow mold carrier parts to hold blow mold parts, wherein at least one of these blow mold carrier parts is mobile in relation to the other blow mold carrier part, and wherein the blowing stations each comprise a carrier element to carry at least one blow mold carrier part. The device includes a clean room within which the plastic preforms can be expanded into plastic containers. The blow mold carrier parts together with the carrier element form a unit which can be demounted as a whole from the carrier.