Evaluation of decay of painted systems for wood, steel and galvanized steel after 8 years exposure.

The damage of the paint systems have been evaluated by using the well established ASTM-standards on samples exposed for one, two, four and eight years. The dose-response functions for the relation between the air pollutants and the damages have been established by means of two steps. The first step has been to define the lifetime for maintenance intervals for fungus growth on the surfaces, for the cracking of the paint systems for wood and for damage spread from a cut in the film for the paint systems for metals. The second step has been to establish the correlation between the lifetime and selected environmental parameters in a dose-response function by stepwise backward regression analysis.