Three kinds of steel [soft steel (SPHC), carbon steel (SS400), and weathered steel (A588)] were prepared for accelerated corrosion and atmospheric corrosion tests. The results of atmospheric corrosion tests were similar to those of accelerated corrosion tests. A correlation was developed for prediction of atmospheric corrosion rates of steel using atmospheric corrosion factors (i.e. Cl- deposition fluxes, time of wetness, and temperatures). The comparisons between predicted and measured thickness losses due to atmospheric corrosion showed an average error of 31.6%. In addition, Tafel plots were employed to evaluate the corrosion behaviour of the three kinds of steel. The morphology of the cross-sections of specimens exposed outdoors was examined by scanning electron microscopy (SEM). The results of the Tafel extrapolation tests and SEM observations of the surface morphology were similar to those seen in the atmospheric corrosion tests.