Cathodic Protection Tester Practice Exam

The two primary methods of cathodic protection are galvanic (sacrificial anode) protection and impressed current protection. Galvanic protection utilizes sacrificial anodes, typically made of a more reactive metal, which corrode preferentially to the protected metal structure. This method is often applied in environments where a simple, passive protection system is sufficient, such as on pipelines or vessels submerged in water. The anodes provide a continuous supply of electrons to the metal surface, thus preventing the corrosion process. Impressed current protection, on the other hand, involves the use of a power source to drive a current through the metal structure to counteract the electrochemical reactions that cause corrosion. This method allows for greater control and is effective in scenarios where the resistance in the environment is high or when more robust protection is required, such as in large steel structures, tanks, and platforms. These two methods are fundamental in the field of cathodic protection, as they cater to different environmental conditions and requirements of protecting metallic structures from corrosion. Other options, while related to corrosion control, do not specifically define the primary methods used in cathodic protection.