ABYC CORROSION 2026 – QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED ANSWERS | PLUS
RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
CORE DOMAINS
Basics of Matter and Electrochemistry
The Galvanic Series and Galvanic Corrosion
Stray Current Corrosion (Electrolysis)
Cathodic Protection Systems (Sacrificial Anodes & ICCP)
Bonding Systems and ABYC E-2 Standards
Galvanic Isolators and Isolation Transformers
Corrosion Surveys and Troubleshooting
Protective Coatings and Material Selection
AC and DC Electrical Systems as they relate to Corrosion
INTRODUCTION
This comprehensive examination is designed to assess the knowledge and
practical skills of marine technicians seeking certification in corrosion
control. The assessment covers a wide range of topics, from fundamental
electrochemical theory to the application of ABYC standards, including
E-2 (Cathodic Protection) and A-28 (Galvanic Isolators) .
Candidates will be evaluated on their ability to identify, analyze, and
solve complex corrosion issues in the marine environment. The exam
consists of multiple-choice questions and scenario-based problems that
test not only recall but also critical thinking and professional
,decision-making. Success requires a deep understanding of both the
scientific principles of corrosion and the practical steps necessary for
its prevention and mitigation, ensuring the safety and longevity of
marine vessels.
Question 1
When two dissimilar metals are electrically connected and immersed in an electrolyte, the more active metal will
become the anode and corrode. What is this process called?
A. Electrolysis
B. Galvanic Corrosion
C. Crevice Corrosion
D. Pitting Corrosion
🟢 Correct Answer: B. Galvanic Corrosion
🔴 Explanation: Galvanic corrosion is the electrochemical process where one metal corrodes preferentially when in
electrical contact with a more noble metal in the presence of an electrolyte . This is the fundamental principle of a
galvanic cell.
Question 2
Which of the following is the most accurate statement regarding tinned copper wire as per ABYC standards?
A. Tinned wire is mandatory for all marine DC circuits.
B. Tinned wire is only required for AC shore power connections.
C. Tinned wire is recommended to mitigate corrosion, but not required by ABYC.
D. Tinned wire is required for all grounding conductors.
🟢 Correct Answer: C. Tinned wire is recommended to mitigate corrosion, but not required by ABYC.
,🔴 Explanation: Contrary to a common misconception, ABYC does not require the use of tinned wire. It is a best
practice to help mitigate corrosion, but proper installation and drip loops are more critical .
Question 3
A boat is experiencing rapid loss of its zinc anodes. The owner has just installed a new battery charger. What is the
most likely cause of the accelerated anode consumption?
A. The battery charger is not marine-rated and lacks an isolation transformer.
B. The battery charger is connected to the wrong battery bank.
C. The battery charger's output voltage is too low.
D. The battery charger is causing galvanic corrosion.
🟢 Correct Answer: A. The battery charger is not marine-rated and lacks an isolation transformer.
🔴 Explanation: An automotive or non-marine battery charger can allow stray current to pass through the boat's
grounding system into the water, causing rapid electrolysis and anode loss. A marine-rated charger with an isolation
transformer prevents this .
Question 4
According to ABYC standards, what is the minimum gauge for a conductor used in a cathodic bonding system?
A. #8 AWG
B. #10 AWG
C. #12 AWG
D. #14 AWG
🟢 Correct Answer: A. #8 AWG
🔴 Explanation: ABYC E-2 standards require that a wire used as a cathodic bonding conductor be at least #8 AWG to
ensure physical strength and maintain a low-resistance connection .
Question 5
What is the purpose of a galvanic isolator in a shore power system?
A. To protect the boat from lightning strikes.
, B. To block stray DC currents from flowing through the green grounding conductor.
C. To block stray AC currents from flowing through the green grounding conductor.
D. To step down the AC voltage from shore power.
🟢 Correct Answer: B. To block stray DC currents from flowing through the green grounding conductor.
🔴 Explanation: A galvanic isolator is designed to block low-voltage DC galvanic currents that travel on the shore
power's green grounding conductor, preventing them from causing corrosion on the boat. It allows AC fault currents
to pass .
Question 6
A technician finds that a vessel's bronze propeller is showing signs of dezincification. This is a form of which type of
corrosion?
A. Stress corrosion cracking
B. Galvanic corrosion
C. Crevice corrosion
D. Selective leaching
🟢 Correct Answer: D. Selective leaching
🔴 Explanation: Dezincification is the selective removal of zinc from a brass alloy (like bronze), leaving behind a
weakened, porous copper structure. It is a form of selective leaching.
Question 7
Which statement correctly describes a condition of cathodic protection?
A. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 100
mV.
B. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 200
mV.
C. The cathodic protection system shall be capable of inducing and maintaining a minimum positive shift of 200 mV.
D. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 500
RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
CORE DOMAINS
Basics of Matter and Electrochemistry
The Galvanic Series and Galvanic Corrosion
Stray Current Corrosion (Electrolysis)
Cathodic Protection Systems (Sacrificial Anodes & ICCP)
Bonding Systems and ABYC E-2 Standards
Galvanic Isolators and Isolation Transformers
Corrosion Surveys and Troubleshooting
Protective Coatings and Material Selection
AC and DC Electrical Systems as they relate to Corrosion
INTRODUCTION
This comprehensive examination is designed to assess the knowledge and
practical skills of marine technicians seeking certification in corrosion
control. The assessment covers a wide range of topics, from fundamental
electrochemical theory to the application of ABYC standards, including
E-2 (Cathodic Protection) and A-28 (Galvanic Isolators) .
Candidates will be evaluated on their ability to identify, analyze, and
solve complex corrosion issues in the marine environment. The exam
consists of multiple-choice questions and scenario-based problems that
test not only recall but also critical thinking and professional
,decision-making. Success requires a deep understanding of both the
scientific principles of corrosion and the practical steps necessary for
its prevention and mitigation, ensuring the safety and longevity of
marine vessels.
Question 1
When two dissimilar metals are electrically connected and immersed in an electrolyte, the more active metal will
become the anode and corrode. What is this process called?
A. Electrolysis
B. Galvanic Corrosion
C. Crevice Corrosion
D. Pitting Corrosion
🟢 Correct Answer: B. Galvanic Corrosion
🔴 Explanation: Galvanic corrosion is the electrochemical process where one metal corrodes preferentially when in
electrical contact with a more noble metal in the presence of an electrolyte . This is the fundamental principle of a
galvanic cell.
Question 2
Which of the following is the most accurate statement regarding tinned copper wire as per ABYC standards?
A. Tinned wire is mandatory for all marine DC circuits.
B. Tinned wire is only required for AC shore power connections.
C. Tinned wire is recommended to mitigate corrosion, but not required by ABYC.
D. Tinned wire is required for all grounding conductors.
🟢 Correct Answer: C. Tinned wire is recommended to mitigate corrosion, but not required by ABYC.
,🔴 Explanation: Contrary to a common misconception, ABYC does not require the use of tinned wire. It is a best
practice to help mitigate corrosion, but proper installation and drip loops are more critical .
Question 3
A boat is experiencing rapid loss of its zinc anodes. The owner has just installed a new battery charger. What is the
most likely cause of the accelerated anode consumption?
A. The battery charger is not marine-rated and lacks an isolation transformer.
B. The battery charger is connected to the wrong battery bank.
C. The battery charger's output voltage is too low.
D. The battery charger is causing galvanic corrosion.
🟢 Correct Answer: A. The battery charger is not marine-rated and lacks an isolation transformer.
🔴 Explanation: An automotive or non-marine battery charger can allow stray current to pass through the boat's
grounding system into the water, causing rapid electrolysis and anode loss. A marine-rated charger with an isolation
transformer prevents this .
Question 4
According to ABYC standards, what is the minimum gauge for a conductor used in a cathodic bonding system?
A. #8 AWG
B. #10 AWG
C. #12 AWG
D. #14 AWG
🟢 Correct Answer: A. #8 AWG
🔴 Explanation: ABYC E-2 standards require that a wire used as a cathodic bonding conductor be at least #8 AWG to
ensure physical strength and maintain a low-resistance connection .
Question 5
What is the purpose of a galvanic isolator in a shore power system?
A. To protect the boat from lightning strikes.
, B. To block stray DC currents from flowing through the green grounding conductor.
C. To block stray AC currents from flowing through the green grounding conductor.
D. To step down the AC voltage from shore power.
🟢 Correct Answer: B. To block stray DC currents from flowing through the green grounding conductor.
🔴 Explanation: A galvanic isolator is designed to block low-voltage DC galvanic currents that travel on the shore
power's green grounding conductor, preventing them from causing corrosion on the boat. It allows AC fault currents
to pass .
Question 6
A technician finds that a vessel's bronze propeller is showing signs of dezincification. This is a form of which type of
corrosion?
A. Stress corrosion cracking
B. Galvanic corrosion
C. Crevice corrosion
D. Selective leaching
🟢 Correct Answer: D. Selective leaching
🔴 Explanation: Dezincification is the selective removal of zinc from a brass alloy (like bronze), leaving behind a
weakened, porous copper structure. It is a form of selective leaching.
Question 7
Which statement correctly describes a condition of cathodic protection?
A. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 100
mV.
B. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 200
mV.
C. The cathodic protection system shall be capable of inducing and maintaining a minimum positive shift of 200 mV.
D. The cathodic protection system shall be capable of inducing and maintaining a minimum negative shift of 500
