API 653 ABOVEGROUND STORAGE TANK INSPECTOR
CERTIFICATION NEWEST (2026 UPDATE) ACTUAL
PRACTICE QUESTIONS – SET 100 MOST COMMON
EXAM FREQUENTLY TESTED QUESTIONS AND
ANSWERS IN DETAILS 100% VERIFIED EXAM HIGHLY
RECOMMENDABLE FOR GRADE A+
1. A storage tank inspector is reviewing the scope of API 653. Which of the
following best describes the primary purpose of API 653?
A. Design of new storage tanks
B. Inspection, repair, alteration, and reconstruction of tanks
C. Welding procedures for pipelines
D. Environmental compliance regulations
✔ Correct Answer: B (Inspection, repair, alteration, and reconstruction of
tanks)
Explanation: API 653 specifically governs the in-service inspection, repair,
alteration, and reconstruction of aboveground storage tanks, not initial
design which is covered by API 650.
2. Which standard is primarily used for the design and construction of new
aboveground storage tanks?
A. API 570
B. API 510
C. API 650
D. API 653
✔ Correct Answer: C (API 650)
Explanation: API 650 is the governing standard for the design and
construction of new welded steel storage tanks.
3. During an external inspection, which condition is MOST critical to identify?
A. Paint color fading
, B. Roof drainage condition
C. Shell distortion
D. Ladder alignment
✔ Correct Answer: C (Shell distortion)
Explanation: Shell distortion can indicate structural instability or
settlement issues, making it a critical safety concern.
4. What is the minimum required frequency for external inspections of an
aboveground storage tank?
A. Every month
B. Every 6 months
C. Every 5 years
D. As determined by risk-based inspection or at least every 5 years
✔ Correct Answer: D (As determined by risk-based inspection or at least
every 5 years)
Explanation: API 653 allows RBI methods but mandates a maximum
interval of 5 years for external inspections.
5. Which of the following is used to determine corrosion rates in tank shells?
A. Paint thickness gauge
B. Ultrasonic thickness measurements
C. Radiographic film
D. Magnetic particle testing
✔ Correct Answer: B (Ultrasonic thickness measurements)
Explanation: Ultrasonic testing is the standard method for measuring
remaining wall thickness and determining corrosion rates.
6. A tank bottom inspection reveals pitting corrosion. What is the MOST
appropriate evaluation method?
A. Visual estimation only
B. Average thickness calculation
C. Remaining strength factor (RSF)
D. Settlement survey
✔ Correct Answer: C (Remaining strength factor (RSF))
, Explanation: RSF is used to assess localized corrosion such as pitting to
determine structural integrity.
7. Which document must be maintained for the life of the tank?
A. Welding rod certificates
B. Inspection and repair records
C. Employee training logs
D. Paint manufacturer data sheets
✔ Correct Answer: B (Inspection and repair records)
Explanation: API 653 requires maintaining complete inspection and repair
histories for the tank lifecycle.
8. What is the purpose of a hydrostatic test?
A. Check paint adhesion
B. Verify structural integrity and leak tightness
C. Measure corrosion rate
D. Inspect weld quality visually
✔ Correct Answer: B (Verify structural integrity and leak tightness)
Explanation: Hydrostatic testing ensures the tank can safely hold liquid
without leaks or structural failure.
9. Which type of corrosion occurs under tank bottoms due to water
accumulation?
A. Galvanic corrosion
B. Atmospheric corrosion
C. Microbiologically influenced corrosion
D. Soil-side corrosion
✔ Correct Answer: D (Soil-side corrosion)
Explanation: Soil-side corrosion occurs beneath tank bottoms where
moisture accumulates.
10.What is the primary function of a tank annular plate?
A. Support roof structure
B. Provide reinforcement at shell-to-bottom junction
CERTIFICATION NEWEST (2026 UPDATE) ACTUAL
PRACTICE QUESTIONS – SET 100 MOST COMMON
EXAM FREQUENTLY TESTED QUESTIONS AND
ANSWERS IN DETAILS 100% VERIFIED EXAM HIGHLY
RECOMMENDABLE FOR GRADE A+
1. A storage tank inspector is reviewing the scope of API 653. Which of the
following best describes the primary purpose of API 653?
A. Design of new storage tanks
B. Inspection, repair, alteration, and reconstruction of tanks
C. Welding procedures for pipelines
D. Environmental compliance regulations
✔ Correct Answer: B (Inspection, repair, alteration, and reconstruction of
tanks)
Explanation: API 653 specifically governs the in-service inspection, repair,
alteration, and reconstruction of aboveground storage tanks, not initial
design which is covered by API 650.
2. Which standard is primarily used for the design and construction of new
aboveground storage tanks?
A. API 570
B. API 510
C. API 650
D. API 653
✔ Correct Answer: C (API 650)
Explanation: API 650 is the governing standard for the design and
construction of new welded steel storage tanks.
3. During an external inspection, which condition is MOST critical to identify?
A. Paint color fading
, B. Roof drainage condition
C. Shell distortion
D. Ladder alignment
✔ Correct Answer: C (Shell distortion)
Explanation: Shell distortion can indicate structural instability or
settlement issues, making it a critical safety concern.
4. What is the minimum required frequency for external inspections of an
aboveground storage tank?
A. Every month
B. Every 6 months
C. Every 5 years
D. As determined by risk-based inspection or at least every 5 years
✔ Correct Answer: D (As determined by risk-based inspection or at least
every 5 years)
Explanation: API 653 allows RBI methods but mandates a maximum
interval of 5 years for external inspections.
5. Which of the following is used to determine corrosion rates in tank shells?
A. Paint thickness gauge
B. Ultrasonic thickness measurements
C. Radiographic film
D. Magnetic particle testing
✔ Correct Answer: B (Ultrasonic thickness measurements)
Explanation: Ultrasonic testing is the standard method for measuring
remaining wall thickness and determining corrosion rates.
6. A tank bottom inspection reveals pitting corrosion. What is the MOST
appropriate evaluation method?
A. Visual estimation only
B. Average thickness calculation
C. Remaining strength factor (RSF)
D. Settlement survey
✔ Correct Answer: C (Remaining strength factor (RSF))
, Explanation: RSF is used to assess localized corrosion such as pitting to
determine structural integrity.
7. Which document must be maintained for the life of the tank?
A. Welding rod certificates
B. Inspection and repair records
C. Employee training logs
D. Paint manufacturer data sheets
✔ Correct Answer: B (Inspection and repair records)
Explanation: API 653 requires maintaining complete inspection and repair
histories for the tank lifecycle.
8. What is the purpose of a hydrostatic test?
A. Check paint adhesion
B. Verify structural integrity and leak tightness
C. Measure corrosion rate
D. Inspect weld quality visually
✔ Correct Answer: B (Verify structural integrity and leak tightness)
Explanation: Hydrostatic testing ensures the tank can safely hold liquid
without leaks or structural failure.
9. Which type of corrosion occurs under tank bottoms due to water
accumulation?
A. Galvanic corrosion
B. Atmospheric corrosion
C. Microbiologically influenced corrosion
D. Soil-side corrosion
✔ Correct Answer: D (Soil-side corrosion)
Explanation: Soil-side corrosion occurs beneath tank bottoms where
moisture accumulates.
10.What is the primary function of a tank annular plate?
A. Support roof structure
B. Provide reinforcement at shell-to-bottom junction
