DS EN 14015:2004 Specification For The Design And Manufacture Of Site Built, Vertical, Cylindrical, Flat-Bottomed, Above Ground, Welded, Steel Tanks For The Storage Of Liquids At Ambient Temperature And Above Defines the requirements for the materials, design, fabrication, erection, testing and inspection of site built, vertical, cylindrical, flat bottomed, above ground, welded, steel tanks for the storage