API 510 Pressure Vessel Inspector
Certification Practice Exam 100
Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. What is the primary purpose of API 510?
A. Design of new pressure vessels
B. Fabrication of pressure vessels
C. In-service inspection, repair, alteration, and rerating of pressure vessels
D. Welding procedure qualification
Answer: C
Rationale: API 510 governs inspection and maintenance of vessels already in
service, covering inspection, repair, alteration, and rerating activities.
2. Which code provides rules for pressure vessel design and construction?
A. API 510
B. ASME Section VIII
C. API 570
D. API 653
Answer: B
Rationale: ASME Section VIII provides the rules for pressure vessel design and
construction, while API 510 covers in-service inspection.
,3. MAWP stands for:
A. Maximum Allowable Weld Pressure
B. Minimum Allowable Working Pressure
C. Maximum Allowable Working Pressure
D. Maximum Applied Working Pressure
Answer: C
Rationale: MAWP is the maximum pressure at which a vessel can safely
operate under design conditions.
4. Corrosion allowance in pressure vessels is:
A. Extra thickness for welding
B. Extra thickness added to compensate for future corrosion
C. Thickness required by ASME
D. Minimum thickness required
Answer: B
Rationale: Corrosion allowance accounts for expected material loss over the
service life of the vessel.
5. Who is responsible for determining inspection intervals?
A. Manufacturer
B. Operator
C. Authorized inspector with owner/user
D. Government regulatory agency
Answer: C
,Rationale: Inspection intervals are determined by the authorized inspector in
coordination with the owner/user.
6. Risk-Based Inspection methodology is defined in:
A. API 570
B. API 580/581
C. API 653
D. ASME Section IX
Answer: B
Rationale: API 580/581 cover RBI methodology for inspection planning.
7. Internal inspection intervals are determined by:
A. Vessel color
B. Operator preference
C. Corrosion rate and service conditions
D. Manufacturer recommendation only
Answer: C
Rationale: Corrosion rate and service conditions determine the degradation
rate, which influences inspection intervals.
8. Minimum thickness refers to:
A. Design thickness
B. Original thickness
C. Required thickness to safely contain pressure
D. Maximum thickness
Answer: C
, Rationale: Minimum thickness ensures safe operation under pressure and is
the threshold for retirement or repair.
9. CUI stands for:
A. Corrosion under insulation
B. Crack under insulation
C. Coating under insulation
D. Corrosion under inspection
Answer: A
Rationale: CUI is corrosion that occurs beneath insulation where moisture is
trapped.
10. Which method detects internal flaws?
A. PT
B. MT
C. RT/UT
D. VT
Answer: C
Rationale: Radiography (RT) and ultrasonic testing (UT) detect internal
defects.
11. Welding qualifications are per:
A. API 510
B. ASME Section IX
C. API 570
D. API 653
Certification Practice Exam 100
Questions And Correct Answers
(Verified Answers) Plus Rationales
2026 Q&A Instant Download Pdf
1. What is the primary purpose of API 510?
A. Design of new pressure vessels
B. Fabrication of pressure vessels
C. In-service inspection, repair, alteration, and rerating of pressure vessels
D. Welding procedure qualification
Answer: C
Rationale: API 510 governs inspection and maintenance of vessels already in
service, covering inspection, repair, alteration, and rerating activities.
2. Which code provides rules for pressure vessel design and construction?
A. API 510
B. ASME Section VIII
C. API 570
D. API 653
Answer: B
Rationale: ASME Section VIII provides the rules for pressure vessel design and
construction, while API 510 covers in-service inspection.
,3. MAWP stands for:
A. Maximum Allowable Weld Pressure
B. Minimum Allowable Working Pressure
C. Maximum Allowable Working Pressure
D. Maximum Applied Working Pressure
Answer: C
Rationale: MAWP is the maximum pressure at which a vessel can safely
operate under design conditions.
4. Corrosion allowance in pressure vessels is:
A. Extra thickness for welding
B. Extra thickness added to compensate for future corrosion
C. Thickness required by ASME
D. Minimum thickness required
Answer: B
Rationale: Corrosion allowance accounts for expected material loss over the
service life of the vessel.
5. Who is responsible for determining inspection intervals?
A. Manufacturer
B. Operator
C. Authorized inspector with owner/user
D. Government regulatory agency
Answer: C
,Rationale: Inspection intervals are determined by the authorized inspector in
coordination with the owner/user.
6. Risk-Based Inspection methodology is defined in:
A. API 570
B. API 580/581
C. API 653
D. ASME Section IX
Answer: B
Rationale: API 580/581 cover RBI methodology for inspection planning.
7. Internal inspection intervals are determined by:
A. Vessel color
B. Operator preference
C. Corrosion rate and service conditions
D. Manufacturer recommendation only
Answer: C
Rationale: Corrosion rate and service conditions determine the degradation
rate, which influences inspection intervals.
8. Minimum thickness refers to:
A. Design thickness
B. Original thickness
C. Required thickness to safely contain pressure
D. Maximum thickness
Answer: C
, Rationale: Minimum thickness ensures safe operation under pressure and is
the threshold for retirement or repair.
9. CUI stands for:
A. Corrosion under insulation
B. Crack under insulation
C. Coating under insulation
D. Corrosion under inspection
Answer: A
Rationale: CUI is corrosion that occurs beneath insulation where moisture is
trapped.
10. Which method detects internal flaws?
A. PT
B. MT
C. RT/UT
D. VT
Answer: C
Rationale: Radiography (RT) and ultrasonic testing (UT) detect internal
defects.
11. Welding qualifications are per:
A. API 510
B. ASME Section IX
C. API 570
D. API 653
