Supplementary or temporary protection is provided to surfaces which already have some form of permanent or semi-permanent form of protection such as cladding or conversion coating. The supplementary protection may be in the form of a material that can be easily applied and removed, and which will be replaced periodically during the life of the system. Jointing compounds and sealants are examples of this type.
The material may need to provide protection when exposed to a variety of differing corrosive atmospheres, indoors, outdoors either under cover or fully exposed, in a marine environment, under effects of direct sunlight, perhaps in a radiation flux, in the presence of specific chemical corrosives in an industrial environment. During its protective period, the it needs to give adequate freedom from corrosion of bare metal surfaces for a predetermined length of time in manufacture, assembly, storage or distribution. The term of protection will need to be determined for each application, in line with other requirements, and the type of protective selected to suit.