Corrosion damage can lead to large costs in bridge construction worldwide. The bridge construction is assured against corrosion
through development of an environment that keeps a maximum of 50% RH around the steel construction.

The girders, on which the tracks lay upon, can be protected against corrosion by the circulation of dry air through the truss, whereas the corrosion protection paint is expensive and demands maintenance.

Painting the bridge increases the weight. Even affixed
constructions can be dehumidifi ed instead of using corrosion protection paint. A dehumidifi er demands minimal maintenance and saves a lot of time compared to personnel applying corrosion protection paint. Corrosion protection is also necessary in spots very difficult to reach and dry air is often the
preferred method.