The guideline applies to all drinking-water supply systems on properties@ in buildings and on merchant ships (including inland water vessels). By way of analogy@ it is also applicable to all other water supply systems as defined in the TrinkwV@ Section 3. The guideline provides information on the planning@ installation@ start-up@ use@ operation and maintenance of all drinking-water supply systems. For the hygiene requirements of the TrinkwV to be fulfilled@ all components of the drinking-water supply system must be delivered in proper hygiene condition. Manufacturers@ wholesalers and the system installer are equally responsible for ensuring this. Legal duties arise from contractual obligations and duties (such as the obligation to notify the liability insurance company of circumstances increasing any risks)@ legal requirements and the creation of possible causes of risks (such as the start-up of equipment).