AMPP CATHODIC PROTECTION TECHNOLOGIST
LEVEL 3 (CP3) EXAM – QUESTIONS AND ANSWERS
| VERIFIED AND WELL DETAILED ANSWERS | PLUS
RATIONALES | DOWNLOAD AND PASS | LATEST
EXAM UPDATE 2026/2027
AMPP Cathodic Protection Technologist Level 3 (CP3) Practice Exam
PART 1: CATHODIC PROTECTION FUNDAMENTALS & CORROSION THEORY
1. The primary purpose of cathodic protection is to:
A) Increase metal hardness
B) Reduce the corrosion rate of a metal structure by making it the cathode of an
electrochemical cell
C) Increase coating thickness
D) Eliminate all electrical resistance
Correct Answer: B) Reduce the corrosion rate of a metal structure by making it
the cathode of an electrochemical cell
Explanation: Cathodic protection reduces corrosion by shifting the structure's
potential in the negative direction and causing it to function as a cathode in an
electrochemical cell .
2. Corrosion of steel is fundamentally a:
A) Mechanical reaction
B) Thermal reaction
,C) Electrochemical reaction
D) Magnetic reaction
Correct Answer: C) Electrochemical reaction
Explanation: Corrosion involves the anodic dissolution of metal and cathodic
reactions occurring simultaneously at the metal-electrolyte interface .
3. In a corrosion cell, metal loss occurs at the:
A) Cathode
B) Electrolyte
C) Anode
D) Metallic connection
Correct Answer: C) Anode
Explanation: The anode is the electrode where oxidation (metal dissolution)
occurs. Electrons are released at the anode and travel through the metallic path to
the cathode .
4. The principle of galvanic cathodic protection involves:
A) Using an external power source
B) Using a more anodic metal (sacrificial anode) to protect the cathodic metal
structure
C) Applying a protective coating
D) Increasing the electrical resistance
Correct Answer: B) Using a more anodic metal (sacrificial anode) to protect the
cathodic metal structure
Explanation: Galvanic cathodic protection uses a more active metal (sacrificial
anode) that corrodes preferentially, protecting the cathodic structure .
,5. Which materials are commonly used as sacrificial anodes in galvanic cathodic
protection systems?
A) Iron and steel
B) Zinc, magnesium, and aluminum
C) Copper and brass
D) Lead and tin
Correct Answer: B) Zinc, magnesium, and aluminum
Explanation: Common sacrificial anode materials include zinc, magnesium, and
aluminum .
6. Impressed current cathodic protection (ICCP) systems use an external power
source to:
A) Heat the protected structure
B) Provide a continuous flow of electrical current to make the structure a cathode
C) Increase the corrosion rate
D) Measure soil resistivity
Correct Answer: B) Provide a continuous flow of electrical current to make the
structure a cathode
Explanation: ICCP systems use an external power source to supply a continuous
current, forcing the protected structure to become a cathode .
7. Which of the following best describes the electrochemical principle of
cathodic protection?
A) Making the metal surface more anodic
B) Shifting the potential of the metal in the negative direction to reduce the
corrosion rate
C) Increasing the electrical resistance of the metal
D) Applying a magnetic field to the metal
, Correct Answer: B) Shifting the potential of the metal in the negative direction
to reduce the corrosion rate
Explanation: Cathodic protection works by polarizing the structure, shifting its
potential in the negative direction and into the immunity region where corrosion
is thermodynamically unfavorable .
8. The exchange of electrons between metal atoms and ions in the electrolyte
defines:
A) A mechanical reaction
B) An electrochemical reaction
C) A thermal reaction
D) A nuclear reaction
Correct Answer: B) An electrochemical reaction
Explanation: Corrosion is a chemical reaction that involves the transfer of
electrons between the metal surface and the surrounding electrolyte .
9. According to commonly used cathodic protection criteria, a polarized
potential of at least -0.850 V is measured against which reference electrode?
A) Silver/Silver Chloride (Ag/AgCl)
B) Saturated Calomel Electrode (SCE)
C) Copper/Copper Sulfate (CSE)
D) Standard Hydrogen Electrode (SHE)
Correct Answer: C) Copper/Copper Sulfate (CSE)
Explanation: The -850 mV criterion is one of the most widely recognized CP
criteria for steel in soil, measured against a copper/copper sulfate reference
electrode .
LEVEL 3 (CP3) EXAM – QUESTIONS AND ANSWERS
| VERIFIED AND WELL DETAILED ANSWERS | PLUS
RATIONALES | DOWNLOAD AND PASS | LATEST
EXAM UPDATE 2026/2027
AMPP Cathodic Protection Technologist Level 3 (CP3) Practice Exam
PART 1: CATHODIC PROTECTION FUNDAMENTALS & CORROSION THEORY
1. The primary purpose of cathodic protection is to:
A) Increase metal hardness
B) Reduce the corrosion rate of a metal structure by making it the cathode of an
electrochemical cell
C) Increase coating thickness
D) Eliminate all electrical resistance
Correct Answer: B) Reduce the corrosion rate of a metal structure by making it
the cathode of an electrochemical cell
Explanation: Cathodic protection reduces corrosion by shifting the structure's
potential in the negative direction and causing it to function as a cathode in an
electrochemical cell .
2. Corrosion of steel is fundamentally a:
A) Mechanical reaction
B) Thermal reaction
,C) Electrochemical reaction
D) Magnetic reaction
Correct Answer: C) Electrochemical reaction
Explanation: Corrosion involves the anodic dissolution of metal and cathodic
reactions occurring simultaneously at the metal-electrolyte interface .
3. In a corrosion cell, metal loss occurs at the:
A) Cathode
B) Electrolyte
C) Anode
D) Metallic connection
Correct Answer: C) Anode
Explanation: The anode is the electrode where oxidation (metal dissolution)
occurs. Electrons are released at the anode and travel through the metallic path to
the cathode .
4. The principle of galvanic cathodic protection involves:
A) Using an external power source
B) Using a more anodic metal (sacrificial anode) to protect the cathodic metal
structure
C) Applying a protective coating
D) Increasing the electrical resistance
Correct Answer: B) Using a more anodic metal (sacrificial anode) to protect the
cathodic metal structure
Explanation: Galvanic cathodic protection uses a more active metal (sacrificial
anode) that corrodes preferentially, protecting the cathodic structure .
,5. Which materials are commonly used as sacrificial anodes in galvanic cathodic
protection systems?
A) Iron and steel
B) Zinc, magnesium, and aluminum
C) Copper and brass
D) Lead and tin
Correct Answer: B) Zinc, magnesium, and aluminum
Explanation: Common sacrificial anode materials include zinc, magnesium, and
aluminum .
6. Impressed current cathodic protection (ICCP) systems use an external power
source to:
A) Heat the protected structure
B) Provide a continuous flow of electrical current to make the structure a cathode
C) Increase the corrosion rate
D) Measure soil resistivity
Correct Answer: B) Provide a continuous flow of electrical current to make the
structure a cathode
Explanation: ICCP systems use an external power source to supply a continuous
current, forcing the protected structure to become a cathode .
7. Which of the following best describes the electrochemical principle of
cathodic protection?
A) Making the metal surface more anodic
B) Shifting the potential of the metal in the negative direction to reduce the
corrosion rate
C) Increasing the electrical resistance of the metal
D) Applying a magnetic field to the metal
, Correct Answer: B) Shifting the potential of the metal in the negative direction
to reduce the corrosion rate
Explanation: Cathodic protection works by polarizing the structure, shifting its
potential in the negative direction and into the immunity region where corrosion
is thermodynamically unfavorable .
8. The exchange of electrons between metal atoms and ions in the electrolyte
defines:
A) A mechanical reaction
B) An electrochemical reaction
C) A thermal reaction
D) A nuclear reaction
Correct Answer: B) An electrochemical reaction
Explanation: Corrosion is a chemical reaction that involves the transfer of
electrons between the metal surface and the surrounding electrolyte .
9. According to commonly used cathodic protection criteria, a polarized
potential of at least -0.850 V is measured against which reference electrode?
A) Silver/Silver Chloride (Ag/AgCl)
B) Saturated Calomel Electrode (SCE)
C) Copper/Copper Sulfate (CSE)
D) Standard Hydrogen Electrode (SHE)
Correct Answer: C) Copper/Copper Sulfate (CSE)
Explanation: The -850 mV criterion is one of the most widely recognized CP
criteria for steel in soil, measured against a copper/copper sulfate reference
electrode .
