Collecting trays are a preventive measure against environmental pollution. During storage, they are intended to prevent leaked substances and liquids from entering the soil or water. Different legal requirements apply to the storage of hazardous materials. For example, the sump tray must be able to collect at least 10% of the total storage volume or the largest stored container size. In water protection areas, 100% of the collection volume must be available for the stored goods. Depending on the type of stored goods, sump trays made of reinforced concrete, sheet steel or plastic are used.
Detailed information can be found in the so-called "Steel Tank Directive" or the "Directive on the requirements for catch basins aus steel with a volume of up to 1,000 litres (StawaR)".which is available as "September 2011 version" at the German Institute for Structural Engineering (DIBt) is available for download.