Most of the requirements is to retain the original appearance of the building. When you determine the types to use stainless steel, the main consideration is the requirement of aesthetic standards, location of atmospheric corrosion and to clean up system. However, other applications more and more seeking integrity of the structure or impermeability. For example, industrial roof and side wall of the building. In these applications, the owner of the construction cost may be more important than the aesthetic, the surface is not very clean or you can. In the dry indoor environment with 430 stainless steel effect is pretty good. However, in both rural and urban to outdoor to maintain its appearance, it needs regular cleaning. In seriously polluted industrial areas and coastal areas, the surface is very dirty, even rust. But to get the aesthetic effect in the outdoor environment, will be made of nickel - containing stainless steel. Therefore, 304 stainless steel is widely used for walls, side walls, roofs and other architectural uses, but erosion of serious industrial or marine atmosphere, preferably made of 316 stainless steel. Now, people are fully aware of the advantages of stainless steel used in the application in the structure. There are several design criteria include 304 and 316 stainless steel. Because the " bipolar " 2,205 has good corrosion resistance of stainless steel and high tensile strength and proof strength as one, so this steel is also included in the European guidelines.