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AMPP Cathodic Protection Specialist Level 1 (CP1)
Certification Exam QUESTIONS AND VERIFIED
ANSWERS WITH RATIONALES JUST RELEASED
AMPP Cathodic Protection Specialist Level 1 (CP1) Certification Exam
EXAM SUMMARIZED COMPRESSED POINT FORM CONTENT AREAS COVERED BY THE TITLE
• Corrosion Fundamentals: Basic electrochemistry, corrosion cells (anode/cathode reactions),
why metals corrode in soil/water, factors affecting corrosion rate (soil resistivity, pH, oxygen).
• Basic Electricity & Electrical Laws: Ohm's law (V=IR), voltage, current, resistance, circuit types
(series/parallel), polarity concepts for corrosion activity, use of shunts for current measurement
in rectifiers/bonds.
• Cathodic Protection Theory & Principles: How CP converts the structure into a cathode,
protective current concepts, the "-850 mV vs. Cu/CuSO₄" criterion for buried/submerged
structures, IR drop considerations.
• CP Systems: Galvanic (sacrificial anode) systems vs. Impressed Current Cathodic Protection
(ICCP) systems; their components, applications, and differences.
• CP Field Measurement Techniques: Structure-to-soil potential (ON/OFF readings), voltage and
current measurements, soil resistivity testing, pipe/cable locating, rectifier readings,
depolarization tests.
• Reference Electrodes: Use, maintenance, and precautions for reference cells (particularly
Cu/CuSO₄), understanding voltage gradient errors.
• CP Components & Equipment: Test stations, rectifiers, galvanic anodes, impressed current
anodes, bonds, digital multimeters, data loggers, clamp-on ammeters.
• Field Procedures: Close interval surveys (CIS), structure-to-soil measurement techniques,
holiday detection basics, continuity tests, shorts identification, periodic surveys to confirm CP
effectiveness.
• Interference: Stray current interference (AC & DC), identification of foreign current sources,
interference effects on structures.
• Safety & Standards: NACE/AMPP SP0169, electrical safety in field testing, confined space
awareness, hazard identification and Job Safety Analysis (JSA), code requirements.
• Interpretation & Reporting: Interpret CP data, identify underprotection vs. overprotection,
recognize coating defect impacts, basic mapping, report preparation, record keeping.
1. What is the primary goal of a cathodic protection (CP) system in corrosion control?
A) To increase the corrosion rate of the protected structure
B) To convert the protected metallic structure into a cathode, thereby reducing its corrosion
C) To increase the electrical resistance of the soil around the structure
D) To create an electrical connection between two dissimilar metals
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Answer: B
Rationale: Cathodic protection reduces corrosion by making the entire structure a cathode, preventing
anodic metal dissolution. The protected metal becomes the cathode of a corrosion cell.
2. Which device is most commonly used in the field to measure the structure-to-soil potential of a
buried pipeline?
A) An ohmmeter, connected between the pipe and a grounding rod
B) A high-impedance voltmeter connected to a Cu/CuSO₄ reference electrode and the structure
C) A clamp-on ammeter placed around the pipe
D) A soil resistivity meter
Answer: B
Rationale: The standard method for measuring CP effectiveness is to use a high-impedance voltmeter
with a stable reference electrode, such as a copper-copper sulfate (Cu/CuSO₄) half-cell, to measure the
potential difference between the structure and the surrounding electrolyte.
3. According to NACE SP0169, which of the following is a commonly accepted criterion for adequate
cathodic protection of a buried steel structure?
A) A negative (cathodic) potential of at least -0.85 V as measured with a Cu/CuSO₄ reference electrode,
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with IR drop considered
B) A positive (anodic) potential of +0.85 V as measured with a Cu/CuSO₄ reference electrode
C) An AC voltage reading of less than 5 volts on the structure
D) A current density of 5 mA/ft² at the structure's surface
Answer: A
Rationale: The -0.85 V (vs. Cu/CuSO₄) is the most widely used instant-off potential criterion for CP. It is
crucial to account for or minimize the IR drop (voltage drop in the electrolyte) to get an accurate
measurement.
4. What is the primary purpose of the rectifier in an impressed current cathodic protection (ICCP)
system?
A) To convert the DC current from the power source to AC for the anodes
B) To measure the current output of the anodes
C) To convert alternating current (AC) from the power source to direct current (DC) for the CP circuit
D) To act as a sacrificial anode to protect the structure
Answer: C
Rationale: ICCP systems use an external power source. The rectifier is the key component that converts
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AC power into the DC power required for the CP circuit, allowing the anodes to discharge protective
current.
5. A technician measures a structure-to-soil potential of -800 mV vs. Cu/CuSO₄. Is this structure
considered to be meeting the basic -850 mV criterion for cathodic protection?
A) Yes, as it is within 50 mV of the criterion
B) No, the potential must be at least -850 mV to meet the criterion
C) Yes, if the reading was taken during a time of high soil resistivity
D) No, because the criterion is for positive potentials only
Answer: B
Rationale: The -850 mV criterion is a minimum threshold. A reading of -800 mV is less negative than -850
mV, indicating the structure is not meeting the required protection level based on this single criterion.
6. Stray current corrosion interference is primarily caused by:
A) High-quality protective coatings on the pipeline
B) External electrical currents entering the soil and discharging from the structure at other locations
C) Low soil resistivity near the pipeline
D) The presence of excess anode material on the CP system
AMPP Cathodic Protection Specialist Level 1 (CP1)
Certification Exam QUESTIONS AND VERIFIED
ANSWERS WITH RATIONALES JUST RELEASED
AMPP Cathodic Protection Specialist Level 1 (CP1) Certification Exam
EXAM SUMMARIZED COMPRESSED POINT FORM CONTENT AREAS COVERED BY THE TITLE
• Corrosion Fundamentals: Basic electrochemistry, corrosion cells (anode/cathode reactions),
why metals corrode in soil/water, factors affecting corrosion rate (soil resistivity, pH, oxygen).
• Basic Electricity & Electrical Laws: Ohm's law (V=IR), voltage, current, resistance, circuit types
(series/parallel), polarity concepts for corrosion activity, use of shunts for current measurement
in rectifiers/bonds.
• Cathodic Protection Theory & Principles: How CP converts the structure into a cathode,
protective current concepts, the "-850 mV vs. Cu/CuSO₄" criterion for buried/submerged
structures, IR drop considerations.
• CP Systems: Galvanic (sacrificial anode) systems vs. Impressed Current Cathodic Protection
(ICCP) systems; their components, applications, and differences.
• CP Field Measurement Techniques: Structure-to-soil potential (ON/OFF readings), voltage and
current measurements, soil resistivity testing, pipe/cable locating, rectifier readings,
depolarization tests.
• Reference Electrodes: Use, maintenance, and precautions for reference cells (particularly
Cu/CuSO₄), understanding voltage gradient errors.
• CP Components & Equipment: Test stations, rectifiers, galvanic anodes, impressed current
anodes, bonds, digital multimeters, data loggers, clamp-on ammeters.
• Field Procedures: Close interval surveys (CIS), structure-to-soil measurement techniques,
holiday detection basics, continuity tests, shorts identification, periodic surveys to confirm CP
effectiveness.
• Interference: Stray current interference (AC & DC), identification of foreign current sources,
interference effects on structures.
• Safety & Standards: NACE/AMPP SP0169, electrical safety in field testing, confined space
awareness, hazard identification and Job Safety Analysis (JSA), code requirements.
• Interpretation & Reporting: Interpret CP data, identify underprotection vs. overprotection,
recognize coating defect impacts, basic mapping, report preparation, record keeping.
1. What is the primary goal of a cathodic protection (CP) system in corrosion control?
A) To increase the corrosion rate of the protected structure
B) To convert the protected metallic structure into a cathode, thereby reducing its corrosion
C) To increase the electrical resistance of the soil around the structure
D) To create an electrical connection between two dissimilar metals
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Answer: B
Rationale: Cathodic protection reduces corrosion by making the entire structure a cathode, preventing
anodic metal dissolution. The protected metal becomes the cathode of a corrosion cell.
2. Which device is most commonly used in the field to measure the structure-to-soil potential of a
buried pipeline?
A) An ohmmeter, connected between the pipe and a grounding rod
B) A high-impedance voltmeter connected to a Cu/CuSO₄ reference electrode and the structure
C) A clamp-on ammeter placed around the pipe
D) A soil resistivity meter
Answer: B
Rationale: The standard method for measuring CP effectiveness is to use a high-impedance voltmeter
with a stable reference electrode, such as a copper-copper sulfate (Cu/CuSO₄) half-cell, to measure the
potential difference between the structure and the surrounding electrolyte.
3. According to NACE SP0169, which of the following is a commonly accepted criterion for adequate
cathodic protection of a buried steel structure?
A) A negative (cathodic) potential of at least -0.85 V as measured with a Cu/CuSO₄ reference electrode,
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with IR drop considered
B) A positive (anodic) potential of +0.85 V as measured with a Cu/CuSO₄ reference electrode
C) An AC voltage reading of less than 5 volts on the structure
D) A current density of 5 mA/ft² at the structure's surface
Answer: A
Rationale: The -0.85 V (vs. Cu/CuSO₄) is the most widely used instant-off potential criterion for CP. It is
crucial to account for or minimize the IR drop (voltage drop in the electrolyte) to get an accurate
measurement.
4. What is the primary purpose of the rectifier in an impressed current cathodic protection (ICCP)
system?
A) To convert the DC current from the power source to AC for the anodes
B) To measure the current output of the anodes
C) To convert alternating current (AC) from the power source to direct current (DC) for the CP circuit
D) To act as a sacrificial anode to protect the structure
Answer: C
Rationale: ICCP systems use an external power source. The rectifier is the key component that converts
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AC power into the DC power required for the CP circuit, allowing the anodes to discharge protective
current.
5. A technician measures a structure-to-soil potential of -800 mV vs. Cu/CuSO₄. Is this structure
considered to be meeting the basic -850 mV criterion for cathodic protection?
A) Yes, as it is within 50 mV of the criterion
B) No, the potential must be at least -850 mV to meet the criterion
C) Yes, if the reading was taken during a time of high soil resistivity
D) No, because the criterion is for positive potentials only
Answer: B
Rationale: The -850 mV criterion is a minimum threshold. A reading of -800 mV is less negative than -850
mV, indicating the structure is not meeting the required protection level based on this single criterion.
6. Stray current corrosion interference is primarily caused by:
A) High-quality protective coatings on the pipeline
B) External electrical currents entering the soil and discharging from the structure at other locations
C) Low soil resistivity near the pipeline
D) The presence of excess anode material on the CP system
