California ICC UST Service Technician Practice Exam

What are the approved cathodic protection methods?

1. Electrical insulation and passive systems

2. Sacrificial anodes and impressed current systems

3. Corrosion inhibitors and cleaning agents

4. Cathodic disbonding and chemical coatings

The correct answer is: Sacrificial anodes and impressed current systems

The approved cathodic protection methods include sacrificial anodes and impressed current systems. These methods are essential for preventing corrosion in underground storage tanks (USTs) by providing a means to control the electrochemical reactions that cause corrosion. Sacrificial anodes work by utilizing a more reactive metal that will corrode preferentially, thus protecting the tank structure. This type of system is simple to install and maintain, making it efficient for various applications. Impressed current systems, on the other hand, use an external power source to provide a continuous flow of current to the anodes, ensuring effective protection, even in environments where sacrificial anodes might not be sufficient. Other choices include corrosion inhibitors and cleaning agents, which are important for different aspects of corrosion management but do not actually provide cathodic protection. Similarly, options like electrical insulation and passive systems may help minimize corrosion risk but do not actively prevent corrosion through an electrochemical method. Cathodic disbonding refers to a failure mechanism that can occur with protective coatings and does not represent a method of cathodic protection itself.