An additional coating or surface treatment can be used.
To assess the performance of such treatments appropriate relevant international standards may be used.
The IEC 60068 series gives information on environmental testing procedures and severity of tests.
Characteristics of materials coatings and painting should be stated by the manufacturer. Additional information is given in Annex F.
If the enclosure is part of the main earthing conductor system, precautions shall be taken to prevent corrosion of the elements and contact surfaces in the earthing current path, in order to maintain the current-carrying capacity during its expected service lifetime.