Corrosion of old and historic monuments can be measured using a combination of visual investigation, non-destructive structural and chemical analysis. This technique makes it possible to piece together the story of any past and present corrosion taking place. Only then can restorers easily identify the type of corrosion resistant coatings to apply to the monument.
The choice of corrosion resistant coatings depends on the material composition of the surface, as well as its current condition. For example, if the monument has a bronze substrate, the corrosion resistant coatings can be an acrylic-based coating that will not produce a galvanic reaction with the substrate, preventing further corrosion and oxidation from taking place. Such corrosion resistant coatings will require no further maintenance work in the future, because the bronze monument is guaranteed long-term protection with no adverse galvanic reaction taking place, until such time that the corrosion resistant coatings itself met its point of failure or the end of its useful life.
In the event that a corrosive patina has formed on the surface to discolor the monument, a patina removal method should be chemically tested first before being applied on the actual surface. Once the surface is free of this patina, it can now be treated with the appropriate corrosion resistant coatings. Restorers have to be careful with the choice of corrosion resistant coatings to use for surface protection, because the choice will affect any future maintenance work done on the monument. If mere waxing is done to the monument, it leads to frequent future maintenance. On the other hand, other corrosion resistant coatings also have their pros and cons, and the restorers must carefully identify the right coatings for the monument.
