Coating Failures allow contaminants to reach bare steel.

1. Exposure to Oxygen and Moisture
• When steel comes into contact with impure water and oxygen, it undergoes an electrochemical reaction.
• This reaction forms iron oxide, commonly known as rust, black oxides, and pack rust which weakens the metal through pit corrosion, steel thinning, weakening of fasteners or wire rope deterioration over time.

2. Chloride Ions (Coastal regions, or Winter Environments)
• Chlorides from seawater or de-icing salts can penetrate steel’s protective layer.
• This accelerates corrosion, especially in bridges, marine structures, and vehicles exposed to road salts.
3. Air Pollution and Acid Rain
• Pollutants like sulphur dioxide and nitrogen oxides contribute to acid rain.
• Acid rain lowers the pH of water, making it more corrosive and speeding up steel degradation.

Corrosion is the by-product of corrosive contaminates, water and oxygen making its way to steel substrate. Contamination can be result of:

1. Contaminated Substrate: Contaminates were not removed from the steel substrate during surface preparation prior the application of the coating system.  

2. Crevice Corrosion: Hard film form paints were used to cover up moving connections and the applied coating micro-cracked at the connection movement.

3. Pack Rust: The inside of the connection had not been properly flushed out, nor chemically  neutralized, nor treated with the right field proven chemistry to neutralize the corrosion hotspot, nor coated with a flexible coating system that flexes with the moving connection without microcracking.

4. Ponding: When matter (leaves, mud, etc.) pool onto a steel surface, the existing coating can become stressed enough to fail prematurely. Drainage issues should be addressed to prevent such mishaps.