API 653 Exam Questions and Correct Answers
(Verified Answers) Plus Rationales 2026 Q&A |
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1. Which standard governs aboveground storage tank inspection,
repair, alteration, and reconstruction?
A) API 570
B) API 510
C) API 653
D) API 579
Answer: C) API 653
Rationale: API 653 is the governing code for inspection, repair,
alteration, and reconstruction of aboveground storage tanks.
2. What is the primary purpose of an external inspection?
A) Internal corrosion assessment
B) Leak detection inside tank
C) Identify external deterioration and safety issues
D) Verify product quality
,Answer: C) Identify external deterioration and safety issues
Rationale: External inspections focus on corrosion, settlement, and
visible damage.
3. When is a formal internal inspection typically required?
A) Every 6 months
B) Based on corrosion rate and risk assessment
C) Only after failure
D) Every 10 years regardless of condition
Answer: B) Based on corrosion rate and risk assessment
Rationale: Inspection intervals are based on corrosion rate, service, and
risk-based evaluation.
4. What is tank bottom settlement primarily associated with?
A) Welding defects
B) Foundation issues
C) Paint failure
D) Roof corrosion
,Answer: B) Foundation issues
Rationale: Settlement is caused by unstable or uneven foundation
conditions.
5. Which of the following is a common type of corrosion in tank
bottoms?
A) Galvanic corrosion
B) Atmospheric corrosion
C) Soil-side corrosion
D) Crevice corrosion only
Answer: C) Soil-side corrosion
Rationale: Soil-side corrosion occurs due to moisture and contaminants
under tank bottoms.
6. What is the minimum thickness required for continued tank service
determined by?
A) Manufacturer recommendation only
B) API 653 calculations
C) Inspector preference
D) Paint thickness
, Answer: B) API 653 calculations
Rationale: Minimum thickness is calculated using API 653 formulas and
corrosion rates.
7. Which nondestructive testing method is commonly used for weld
inspection?
A) Radiography
B) Visual only
C) Hammer testing
D) Pressure drop test
Answer: A) Radiography
Rationale: Radiography is widely used to detect internal weld defects.
8. What is the function of a tank shell course?
A) Store roof water
B) Contain internal pressure and product
C) Support floating roof only
D) Drain sediment
Answer: B) Contain internal pressure and product
Rationale: Shell courses provide structural containment of stored liquid.
(Verified Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which standard governs aboveground storage tank inspection,
repair, alteration, and reconstruction?
A) API 570
B) API 510
C) API 653
D) API 579
Answer: C) API 653
Rationale: API 653 is the governing code for inspection, repair,
alteration, and reconstruction of aboveground storage tanks.
2. What is the primary purpose of an external inspection?
A) Internal corrosion assessment
B) Leak detection inside tank
C) Identify external deterioration and safety issues
D) Verify product quality
,Answer: C) Identify external deterioration and safety issues
Rationale: External inspections focus on corrosion, settlement, and
visible damage.
3. When is a formal internal inspection typically required?
A) Every 6 months
B) Based on corrosion rate and risk assessment
C) Only after failure
D) Every 10 years regardless of condition
Answer: B) Based on corrosion rate and risk assessment
Rationale: Inspection intervals are based on corrosion rate, service, and
risk-based evaluation.
4. What is tank bottom settlement primarily associated with?
A) Welding defects
B) Foundation issues
C) Paint failure
D) Roof corrosion
,Answer: B) Foundation issues
Rationale: Settlement is caused by unstable or uneven foundation
conditions.
5. Which of the following is a common type of corrosion in tank
bottoms?
A) Galvanic corrosion
B) Atmospheric corrosion
C) Soil-side corrosion
D) Crevice corrosion only
Answer: C) Soil-side corrosion
Rationale: Soil-side corrosion occurs due to moisture and contaminants
under tank bottoms.
6. What is the minimum thickness required for continued tank service
determined by?
A) Manufacturer recommendation only
B) API 653 calculations
C) Inspector preference
D) Paint thickness
, Answer: B) API 653 calculations
Rationale: Minimum thickness is calculated using API 653 formulas and
corrosion rates.
7. Which nondestructive testing method is commonly used for weld
inspection?
A) Radiography
B) Visual only
C) Hammer testing
D) Pressure drop test
Answer: A) Radiography
Rationale: Radiography is widely used to detect internal weld defects.
8. What is the function of a tank shell course?
A) Store roof water
B) Contain internal pressure and product
C) Support floating roof only
D) Drain sediment
Answer: B) Contain internal pressure and product
Rationale: Shell courses provide structural containment of stored liquid.
