This guideline applies to the operation of sanitary systems. In particular, it refers to drainage systems excluding systems relying on natural drainage (infiltration) or on subterranean collection in perforated drain pipes, greywater systems, drinking-water supply systems including wall hydrants, fire-fighting installations, non-drinking-water systems, service-water systems, greywater recycling systems, stormwater harvesting systems.Building services in swimming baths are not within the scope of this guideline; they are governed by, e.g., VDI 2089. Gas installations are not part of this guideline too.This guideline is intended to describe the specified normal operation of sanitary systems interconnected with other building services, while ensuring human health and protecting the environment.