Standpipes are used for taking water from the public mains supply via underground hydrants. Here a distinction is made in the following areas: fire water and drinking water. The standpipe inlet differs from country to country. Germany has four different sizes. Standpipes with a base for garden hydrants are used for irrigation purposes. Standpipes with DN 50 base are mainly used in industry and in the Wuerttemberger area. Standpipes with DN 80 base are commonly used in public supply networks in the rest of Germany. Standpipes for underground hydrants DN 100 are predominantly used in pipeline networks, airports and other locations where there is a large demand for water.