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API 510 practice questions

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Question 1Scope, References, and Organization/Personnel Qualifications

Which API document provides the requirements for in-service inspection, repair, alteration, and rerating of pressure vessels?

  1. API 570
  2. API 576
  3. API 510 Correct answer.
  4. API 653

Explanation

API 510 is the pressure vessel inspection code and governs in-service inspection, repair, alteration, and rerating of pressure vessels in refining and petrochemical service. The other documents listed address piping, storage tanks, and pressure-relieving devices.

Question 2Scope, References, and Organization/Personnel Qualifications

Inspection and repair of pressure-relieving devices is addressed by which document?

  1. API 576 Correct answer.
  2. API 570
  3. API 579-1/ASME FFS-1
  4. API 580

Explanation

Pressure-relieving devices fall outside the scope of API 510 and are handled under API 576, which covers inspection and repair of these devices. API 510 directs the user to that document for such equipment.

Question 3Scope, References, and Organization/Personnel Qualifications

A terminal is establishing an in-service inspection program for its aboveground storage tanks. Which document applies?

  1. API 570
  2. API 510
  3. NB-23
  4. API 653 Correct answer.

Explanation

Aboveground storage tanks are covered by API 653, which addresses inspection, repair, alteration, and reconstruction of tanks. API 510 deliberately excludes tanks from its scope.

Question 4Scope, References, and Organization/Personnel Qualifications

In-service inspection of metallic piping systems in a refinery is governed by which document?

  1. API 570 Correct answer.
  2. API 653
  3. API 576
  4. API 510

Explanation

API 570 covers in-service inspection, repair, alteration, and rerating of piping systems. Piping is excluded from the scope of API 510, so the two codes are applied to different equipment even within the same unit.

Question 5Scope, References, and Organization/Personnel Qualifications

API 510 references which document for welding procedure and performance qualification?

  1. ASME BPVC Section IX Correct answer.
  2. ASME BPVC Section V
  3. ASME PCC-2
  4. ASME BPVC Section VIII Division 1

Explanation

ASME BPVC Section IX contains the welding and brazing procedure and performance qualification rules. Welding performed on vessels and on their repairs must be qualified in accordance with Section IX.

Question 6Scope, References, and Organization/Personnel Qualifications

A fitness-for-service assessment of a vessel with widespread corrosion is performed in accordance with which document?

  1. API 579-1/ASME FFS-1 Correct answer.
  2. API 577
  3. API 571
  4. API 580

Explanation

API 579-1/ASME FFS-1 provides the assessment procedures used to judge whether equipment with damage such as corrosion is fit for continued service. API 510 permits continued operation when such an assessment demonstrates suitability for the intended service.

Question 7Scope, References, and Organization/Personnel Qualifications

Under API 510, nondestructive examination personnel shall be qualified in accordance with which document?

  1. ASNT SNT-TC-1A Correct answer.
  2. API 577
  3. ASME PCC-2
  4. ASME BPVC Section IX

Explanation

NDE personnel must be qualified and certified to ASNT SNT-TC-1A or ANSI/ASNT CP-189, or an equivalent program acceptable to the owner/user. Section IX addresses welding qualifications rather than examiner certification.

Question 8Scope, References, and Organization/Personnel Qualifications

In API 510, the word "shall" identifies a requirement that is:

  1. subject to approval by the jurisdiction
  2. recommended
  3. mandatory Correct answer.
  4. optional at the owner/user's discretion

Explanation

API drafting conventions use "shall" for mandatory requirements, "should" for recommendations, and "may" for permitted options. Knowing these conventions is necessary when applying the code during inspection work.

Question 9Scope, References, and Organization/Personnel Qualifications

A refinery contracts an authorized inspection agency to perform all of its vessel inspections. Who remains responsible for ensuring the vessels are inspected in accordance with API 510?

  1. the authorized inspection agency, since it performs the work
  2. the jurisdiction, since it enforces the code
  3. the vessel manufacturer, for the life of the vessel
  4. the owner/user, who retains overall responsibility Correct answer.

Explanation

API 510 places responsibility for inspection on the owner/user, and that responsibility is not transferred when the activity is performed by an authorized inspection agency or contractor. The owner/user must ensure the program meets the code regardless of who carries out the work.

Question 10Scope, References, and Organization/Personnel Qualifications

An authorized inspector performing work under API 510 shall be employed by:

  1. the repair organization performing the work
  2. the vessel manufacturer
  3. the owner/user's operations department
  4. an authorized inspection agency Correct answer.

Explanation

An authorized inspector is, by definition, employed by an authorized inspection agency such as a jurisdictional authority, an insurance company, or a qualifying owner/user inspection organization. Repair firms, manufacturers, and operations groups are not authorized inspection agencies.

Question 11Scope, References, and Organization/Personnel Qualifications

API 510 defines an alteration as:

  1. a physical change in a component that is not a repair Correct answer.
  2. any hydrostatic test performed after a weld repair
  3. a change in the vessel's inspection interval
  4. work needed to restore a vessel to safe operating condition at design conditions

Explanation

An alteration is a physical change in any component that is not a repair, and it includes changes in geometry, materials, or design conditions. Restoring a vessel to a condition suitable for safe operation is the definition of a repair instead.

Question 12Scope, References, and Organization/Personnel Qualifications

API 510 applies to which phase of a pressure vessel's life?

  1. only the period before the first internal inspection
  2. design and fabrication of new vessels
  3. decommissioning and disposal
  4. the in-service phase Correct answer.

Explanation

API 510 covers vessels once they are placed in service, addressing inspection, repair, alteration, and rerating. Design and fabrication of new vessels are governed by the applicable code of construction, such as ASME Section VIII.

Question 13Scope, References, and Organization/Personnel Qualifications

Before a vessel is rerated to a higher maximum allowable working pressure, API 510 requires:

  1. a documented engineering evaluation and the authorized inspector's approval Correct answer.
  2. a new Manufacturer's Data Report issued by the original manufacturer
  3. a hydrostatic test at twice the proposed new MAWP
  4. notification of all insurers holding policies on the plant

Explanation

Rerating requires a documented engineering evaluation, such as a design review by an engineer experienced in pressure vessel design, along with approval by the authorized inspector. The new rating must be recorded and the nameplate updated as required.

Question 14Scope, References, and Organization/Personnel Qualifications

An individual obtains API 510 inspector certification by:

  1. passing the API 510 examination with the required experience Correct answer.
  2. holding an ASME Section IX welder qualification
  3. being designated by the jurisdictional authority
  4. completing a 40-hour employer training course

Explanation

Certification is administered by API and requires passing the API 510 examination while meeting the education and experience requirements of the certification program. Training courses and welder qualifications do not by themselves confer certification.

Question 15Scope, References, and Organization/Personnel Qualifications

Repairs to pressure-containing components of a vessel shall be performed by:

  1. any crew supervised by a shift operator
  2. the vessel's original manufacturer only
  3. any firm that employs an ASNT Level III examiner
  4. a qualified repair organization Correct answer.

Explanation

Repairs must be made by a repair organization, which may be the owner/user, whose quality program is acceptable to the owner/user, and the work is subject to approval by the inspector. Repair capability, not employment of an examiner, is what qualifies an organization.

Question 16Scope, References, and Organization/Personnel Qualifications

API 510 references which document for welding inspection and metallurgy guidance?

  1. API 571
  2. API 577 Correct answer.
  3. API 580
  4. API 579-1/ASME FFS-1

Explanation

API 577 covers welding inspection and metallurgy and is referenced when welding inspection guidance is needed. The other documents address damage mechanisms, fitness-for-service, and risk-based inspection.

Question 17Scope, References, and Organization/Personnel Qualifications

In API 510, an "inspector" is a person who:

  1. holds an ASME U-stamp certificate of authorization
  2. performs only visual examinations
  3. is qualified and certified to perform inspections under the code Correct answer.
  4. is employed by a jurisdictional authority

Explanation

The code defines an inspector as an individual who is qualified and certified to perform inspections under API 510, which can include API 510 certified inspectors and authorized inspectors. Employment by a jurisdiction or possession of a manufacturer's certificate is not the defining criterion.

Question 18Scope, References, and Organization/Personnel Qualifications

Which document is used to identify damage mechanisms affecting fixed equipment in refining and petrochemical service?

  1. API 571 Correct answer.
  2. API 580
  3. API 579-1/ASME FFS-1
  4. API 576

Explanation

API 571 describes damage mechanisms affecting fixed equipment in the refining and petrochemical industry and is used during inspections to recognize and evaluate damage. It supports, but does not replace, the inspection and fitness-for-service requirements of API 510.

Question 19Scope, References, and Organization/Personnel Qualifications

Which document provides the risk-based inspection framework referenced for planning pressure vessel inspections?

  1. API 576
  2. API 580 Correct answer.
  3. API 577
  4. API 570

Explanation

API 580 is the risk-based inspection standard referenced for establishing inspection plans based on risk. Applying RBI does not relieve the owner/user of the requirement to meet API 510's inspection requirements.

Question 20Scope, References, and Organization/Personnel Qualifications

A corroded area on a vessel shell is weld repaired. Before the vessel is returned to service, the repair shall be approved by:

  1. the repair organization's welding supervisor
  2. the inspector Correct answer.
  3. the owner/user's operations superintendent
  4. the jurisdiction's chief inspector

Explanation

Repairs must be approved by the inspector, who verifies the work was performed in accordance with the applicable requirements before the vessel returns to service. Alterations carry a higher approval requirement and need the authorized inspector.

Question 21Scope, References, and Organization/Personnel Qualifications

API 510 applies to pressure vessels constructed to:

  1. ASME Section I
  2. any code of construction, without restriction
  3. ASME Section IV
  4. ASME Section VIII, Division 1 or Division 2 Correct answer.

Explanation

API 510 applies to vessels built to ASME Section VIII Division 1 or Division 2, and it also accommodates vessels built to other pressure vessel codes acceptable to the jurisdiction. Section I and Section IV cover boilers, which are outside its scope.

Question 22Scope, References, and Organization/Personnel Qualifications

Which of the following changes to an existing vessel is classified as a repair rather than an alteration?

  1. changing the vessel's design temperature rating
  2. replacing a corroded shell course with identical plate Correct answer.
  3. raising the vessel's maximum allowable working pressure
  4. adding a new 3-inch nozzle to the shell

Explanation

Replacing a component with one of the same specification, size, and thickness restores the vessel to its original condition and is therefore a repair. Adding a nozzle, raising the MAWP, or changing the design temperature moves the vessel away from its original design and is an alteration.

Question 23Scope, References, and Organization/Personnel Qualifications

An alteration to a pressure vessel requires approval by:

  1. the inspector only
  2. the repair organization's quality manager
  3. the original manufacturer's engineer
  4. the authorized inspector Correct answer.

Explanation

Because an alteration takes the vessel away from its original design, it requires engineering review and approval by the authorized inspector. A repair, by contrast, is approved by the inspector and is intended to restore the vessel to its design condition.

Question 24Scope, References, and Organization/Personnel Qualifications

A fired steam boiler with a design pressure of 250 psig is being installed. Which code governs its construction?

  1. ASME Section VIII Division 1
  2. API 510
  3. API 560
  4. ASME Section I Correct answer.

Explanation

Fired steam boilers are constructed to ASME BPVC Section I, and boilers are outside the scope of API 510. Section VIII applies to pressure vessels, while API 560 addresses fired heaters.

Question 25Scope, References, and Organization/Personnel Qualifications

Which of the following may serve as an authorized inspection agency?

  1. an independent API 510 certified consultant
  2. a jurisdictional authority that enforces a pressure vessel law Correct answer.
  3. a repair organization holding an R-stamp
  4. an NDE subcontractor employed by the owner/user

Explanation

Authorized inspection agencies include a jurisdictional authority, an insurance company authorized to write boiler and pressure vessel insurance, and an owner/user inspection organization that meets the applicable requirements. Repair firms, NDE subcontractors, and individual consultants do not qualify as agencies.

Question 26Scope, References, and Organization/Personnel Qualifications

Which of the following equipment is within the scope of API 510?

  1. A buried process piping system
  2. A fire-tube steam boiler
  3. A field-erected aboveground storage tank
  4. The shell of a shell-and-tube heat exchanger in refinery service Correct answer.

Explanation

API 510 covers pressure vessels, including heat exchanger shells, in refinery and petrochemical service. Storage tanks, boilers, and piping are addressed by other documents rather than by API 510.

Question 27Scope, References, and Organization/Personnel Qualifications

In addition to pressure vessels themselves, API 510 states that its scope includes which of the following?

  1. Fired process heaters
  2. Pressure-relief devices Correct answer.
  3. Aboveground storage tanks
  4. Rotating pumps and compressors

Explanation

API 510 applies to pressure vessels and to their pressure-relief devices, which are inspected, repaired, and as needed rerated as part of the vessel program. Fired heaters, tanks, and rotating equipment fall outside its scope.

Question 28Scope, References, and Organization/Personnel Qualifications

A requirement of API 510 conflicts with a regulation issued by the jurisdiction in which the vessel is installed. Which requirement applies?

  1. API 510 applies because it is a national consensus standard
  2. The jurisdiction's regulation applies Correct answer.
  3. The vessel's original construction code applies
  4. The owner-user selects whichever requirement is easier to apply

Explanation

API 510 states that where its requirements conflict with the rules of the jurisdiction, the jurisdictional rules govern. The owner-user cannot choose a less stringent alternative, and a consensus standard does not displace a binding regulation.

Question 29Scope, References, and Organization/Personnel Qualifications

Inspection, repair, alteration, and rerating of process piping connected to a pressure vessel are governed by which document?

  1. API 510
  2. API 572
  3. API 570 Correct answer.
  4. ASME Boiler and Pressure Vessel Code, Section VIII, Division 1

Explanation

API 570 governs in-service piping, including its inspection, repair, alteration, and rerating. API 510 addresses the vessel itself, Section VIII addresses vessel construction, and API 572 addresses vessel inspection practices.

Question 30Scope, References, and Organization/Personnel Qualifications

Which API document provides recommended practices for the inspection of pressure vessels in service?

  1. API 572 Correct answer.
  2. API 579-1/ASME FFS-1
  3. API 571
  4. API 580

Explanation

API 572 is the recommended practice for inspection of pressure vessels and is referenced for detailed inspection practices. API 571 covers damage mechanisms, API 579-1/ASME FFS-1 covers fitness-for-service, and API 580 covers risk-based inspection.

Question 31Scope, References, and Organization/Personnel Qualifications

API 510 refers to which document for guidance on the inspection and repair of pressure-relief devices?

  1. API 527
  2. API 520
  3. API 576 Correct answer.
  4. API 598

Explanation

API 576 covers the inspection and repair of pressure-relieving devices and is the reference used for relief device work under API 510. API 520 deals with sizing and selection, API 527 with seat tightness, and API 598 with valve testing.

Question 32Scope, References, and Organization/Personnel Qualifications

A welding procedure specification used to make a repair on a pressure vessel shall be qualified in accordance with which document?

  1. ASME Boiler and Pressure Vessel Code, Section IX Correct answer.
  2. API 577
  3. API 1104
  4. ASME Boiler and Pressure Vessel Code, Section V

Explanation

ASME Section IX contains the rules for qualifying welding procedures and the performance of welders and welding operators, which API 510 invokes for repairs. Section V covers examination methods, API 577 provides welding inspection guidance, and API 1104 covers pipeline welding.

Question 33Scope, References, and Organization/Personnel Qualifications

Which document contains the requirements for the nondestructive examination methods used to examine a pressure vessel?

  1. API 576
  2. ASME Boiler and Pressure Vessel Code, Section V Correct answer.
  3. ASME Boiler and Pressure Vessel Code, Section II
  4. ASME Boiler and Pressure Vessel Code, Section IX

Explanation

ASME Section V contains the requirements for nondestructive examination methods such as radiography, ultrasonic, magnetic particle, and liquid penetrant testing. Section II covers materials, Section IX covers welding qualification, and API 576 covers relief device inspection.

Question 34Scope, References, and Organization/Personnel Qualifications

Under API 510, which statement best describes nondestructive examinations performed on a vessel by personnel other than the inspector?

  1. They may be performed only after the inspector gives written authorization
  2. Qualified examiners perform them, and the inspector evaluates the results Correct answer.
  3. They may be used to approve a repair in place of the inspector's own review
  4. They must be witnessed in person by the inspector to be considered valid

Explanation

API 510 allows examinations to be carried out by qualified examination personnel, with the inspector responsible for evaluating what the examinations reveal. The inspector's approval role cannot be transferred to those who perform the examinations.

Question 35Scope, References, and Organization/Personnel Qualifications

In API 510, the term "jurisdiction" refers to:

  1. The governmental authority responsible for the vessel's location Correct answer.
  2. The organization that fabricated the pressure vessel
  3. The insurance company that provides the plant's boiler and machinery coverage
  4. The owner-user's engineering department

Explanation

The jurisdiction is the governmental body with legal authority over where the vessel is installed, such as a state, provincial, or municipal agency. Insurers, fabricators, and owner-user departments are not jurisdictions.

Question 36Scope, References, and Organization/Personnel Qualifications

Under API 510, which party is responsible for maintaining the inspection records of a pressure vessel?

  1. The owner-user Correct answer.
  2. The authorized inspection agency
  3. The repair organization that last worked on the vessel
  4. The jurisdiction

Explanation

The owner-user is responsible for the vessel, which includes keeping inspection, repair, and rerating records and making them available to the inspector. Inspection agencies and repair organizations perform work on the vessel but do not carry the permanent recordkeeping obligation.

Question 37Scope, References, and Organization/Personnel Qualifications

In-service inspection, repair, alteration, and reconstruction of aboveground storage tanks are governed by which document?

  1. API 653 Correct answer.
  2. API 650
  3. API 570
  4. API 510

Explanation

API 653 covers in-service inspection, repair, alteration, and reconstruction of aboveground storage tanks. API 650 addresses new tank construction, API 570 covers piping, and API 510 covers pressure vessels.

Question 38Scope, References, and Organization/Personnel Qualifications

An owner-user's written inspection procedure specifies less nondestructive examination of a repaired weld than API 510 requires. How should the inspector resolve the difference?

  1. The owner-user's procedure applies because the owner-user owns the vessel
  2. The inspector may choose which requirement to apply and must record the basis
  3. API 510's requirement applies because owner-user documents cannot reduce it Correct answer.
  4. The lesser of the two requirements applies, provided the repair is documented

Explanation

API 510 states mandatory requirements that an owner-user's documents may make more stringent but cannot relax. A procedure calling for less examination than the code requires therefore does not govern the repair.

Question 39Scope, References, and Organization/Personnel Qualifications

Which statement correctly describes how API 510 relates to the ASME Boiler and Pressure Vessel Code for an existing vessel?

  1. Either document may be used for in-service inspection, at the owner-user's option
  2. API 510 replaces the ASME construction code as soon as the vessel enters service
  3. The ASME code governs construction and API 510 governs in-service work Correct answer.
  4. The ASME code governs in-service inspection and API 510 governs new construction

Explanation

The ASME code governs how the vessel was designed and built, while API 510 governs its in-service inspection, repair, alteration, and rerating. The two documents operate in sequence rather than replacing one another.

Question 40Scope, References, and Organization/Personnel Qualifications

A jurisdiction requires every pressure vessel inspector working there to hold a state commission in addition to API 510 certification. An inspector who holds API 510 certification but no state commission performs inspections in that jurisdiction. Which statement is correct?

  1. The inspections are valid if the owner-user accepts them in writing
  2. The inspections are valid because API 510 certification is recognized nationally
  3. The inspections are valid because API 510 certification exceeds state requirements
  4. The inspections do not satisfy the jurisdiction's requirements Correct answer.

Explanation

Where a jurisdiction imposes qualification requirements on inspectors, those requirements apply in addition to API 510, so certification alone does not make the individual acceptable there. The inspector must satisfy the state commission requirement before performing the inspections.

Question 41Inspection, Examination, and Testing

An inspection that is performed while a pressure vessel remains in operation, and that may be accepted in place of an internal inspection, is known as:

  1. An on-stream inspection Correct answer.
  2. A close visual examination of the exterior
  3. A hydrostatic test of the vessel
  4. A third-party audit of the inspection program

Explanation

API 510 recognizes internal, external, and on-stream inspection. An on-stream inspection is carried out while the vessel is in service and may be used in lieu of an internal inspection when the owner-user and the inspector determine that the internal condition can be adequately assessed.

Question 42Inspection, Examination, and Testing

Under API 510, the inspection of an in-service pressure vessel shall be performed by:

  1. An authorized inspector holding a valid API 510 certification Correct answer.
  2. The owner-user's shift supervisor in charge of the unit
  3. Any NDT Level II technician working to a written procedure
  4. A certified welding inspector from the repair contractor

Explanation

API 510 requires that inspection be performed by an authorized pressure vessel inspector, meaning a person who holds a current API 510 certification (or an owner-user designee meeting those qualifications) and who evaluates and accepts the condition of the vessel.

Question 43Inspection, Examination, and Testing

In the absence of a risk-based inspection assessment, the internal inspection interval for a pressure vessel shall never exceed:

  1. 10 years Correct answer.
  2. 15 years
  3. 20 years
  4. 5 years

Explanation

API 510 limits the internal inspection interval to the lesser of one-half the calculated remaining life or 10 years. Ten years is therefore the absolute cap when the half-life calculation exceeds it.

Question 44Inspection, Examination, and Testing

Unless a risk-based inspection assessment is used, the maximum interval between external inspections of a pressure vessel is:

  1. 10 years
  2. 3 years
  3. 1 year
  4. 5 years Correct answer.

Explanation

API 510 requires an external inspection at intervals not exceeding 5 years. The external inspection looks for insulation damage, support deterioration, corrosion under insulation, and visible leaks while the vessel remains in service.

Question 45Inspection, Examination, and Testing

A condition monitoring location (CML) on a pressure vessel is best described as:

  1. A nozzle earmarked by the owner-user for modification
  2. A designated point where thickness readings are taken and trended Correct answer.
  3. The region exposed to the highest design temperature
  4. The point where the pressure relief device is connected

Explanation

CMLs are designated locations, usually including the original thickness measurement locations, where examinations such as ultrasonic thickness gauging are repeated at each inspection. Repeating readings at the same points allows corrosion rates and remaining life to be calculated.

Question 46Inspection, Examination, and Testing

Magnetic particle examination is best suited for finding which of the following?

  1. Wall loss on the inside of a liquid-filled vessel
  2. Lack of fusion in an austenitic stainless steel weld
  3. Surface and near-surface flaws in ferromagnetic steel Correct answer.
  4. Internal porosity deep in a thick stainless steel weld

Explanation

Magnetic particle examination relies on magnetic flux leakage in ferromagnetic materials to reveal surface and slightly subsurface discontinuities. It cannot be applied to austenitic stainless steel and cannot find deeply buried flaws.

Question 47Inspection, Examination, and Testing

The minimum required thickness against which a pressure vessel shell is evaluated is determined by:

  1. The thinnest reading recorded at the previous inspection
  2. The average of the last three ultrasonic thickness readings
  3. The original nominal plate thickness reduced by 12.5%
  4. The construction code using design conditions and corrosion allowance Correct answer.

Explanation

The minimum required thickness is calculated using the rules of the applicable construction code (for example, ASME Section VIII) with the design pressure, temperature, joint efficiency, and corrosion allowance. Measured thicknesses are compared to this value to determine remaining life and fitness for service.

Question 48Inspection, Examination, and Testing

During an internal inspection of a pressure vessel, which activity is normally performed first?

  1. Visual examination of internal surfaces and welds Correct answer.
  2. Full radiography of every longitudinal and circumferential seam
  3. A hydrostatic test at 1.3 times the maximum allowable working pressure
  4. A hardness survey of every nozzle-to-shell weld

Explanation

Visual examination is the primary examination and is done before other methods. It identifies corrosion, cracking, distortion, and lining damage, and it guides where follow-up nondestructive examination is applied.

Question 49Inspection, Examination, and Testing

A pressure vessel has a calculated remaining life of 18 years and no risk-based inspection assessment has been performed. The maximum internal inspection interval is:

  1. 10 years
  2. 18 years
  3. 9 years Correct answer.
  4. 6 years

Explanation

The interval is the lesser of one-half the remaining life (18 ÷ 2 = 9 years) and the 10-year cap. Since 9 years is below the cap, 9 years governs.

Question 50Inspection, Examination, and Testing

A shell course has a minimum required thickness of 0.50 in. The latest ultrasonic reading at the governing CML is 0.62 in, and the corrosion rate is 0.010 in per year. The remaining life is:

  1. 10 years
  2. 12 years Correct answer.
  3. 20 years
  4. 6 years

Explanation

Remaining life equals the corrosion allowance remaining divided by the corrosion rate: (0.62 in − 0.50 in) ÷ 0.010 in/yr = 12 years. The inspection interval would then be set at the lesser of half this value or 10 years.