This guideline provides guidance for the planning, manufacture/installation, commissioning and operation of barrier systems in contamination control. Planer, manufacturer and user of clean environments must define, and lay down in writing, the requirements to be met by the product and its environment. The scope of this guideline includes any type of barrier between the room and the process environment, which serves for contamination control, expressly including dynamic (flow) as well as solid barriers. All types of contamination (particulate, chemical/molecular, biological) are included. The guideline supplements DIN EN ISO 14644-7 in practical aspects.