On new steel surfaces that have been mechanically cleaned, old solid painted surfaces, and galvanized steel surfaces where surface cleaning cannot be done completely,
On the outer surfaces of aboveground storage tanks,
  In the surface and underwater parts of ships,
In order to protect steel and concrete structures and equipment in freshwater and seawater environments against high corrosion, the primer/undercoat is used as a single layer protective coating in cases where color change is not significant.