Predicted Service Life

The corrosion rates of zinc in various environments have been well researched over the years. As a result it is possible to chart the predicted service life for a zinc layer at a given dry film thickness (DFT) in a particular situation. The chart below is based on Hot-Dip Galvanised steel but, as it has already been explained in the Active Protection section, Zinga performs at least as well as HDG in normal atmospheric conditions and even better in marine environments. Please note that the minimum acceptable DFT would normally be 50 microns i.e. the structure should be re-loaded with new Zinga once the zinc has depleted to 50um from its original DFT (normally >120um if using Zinga without topcoats). This is an important point as otherwise this chart could be misleading.

Source: SGS Axa-Med. Service Life is defined as the time to 5% rusting of the steel surface.