NDE on the API 510 Exam: What Section V Covers

The list below comes from section III of the API 510 Body of Knowledge for September 2026 to May 2027, read on 26 October 2026. The Body of Knowledge says the exam covers only the main body of each referenced article, except where noted. Confirm the edition for your window on the effectivity sheet.

The articles on the list

The Body of Knowledge also asks for the general NDE rules in ASME Section VIII, Division 1 (it points to UG, UW and Appendices 4, 6, 8 and 12) and in API 510 itself. It excludes acoustic emission, eddy current and motion radiography.

How to study each method

You do not need to memorize code text. You need to know what each method is for, what it can and cannot find, and what makes a result trustworthy. The words below are ours, so check details against your own copy.

Radiography (Article 2)

Radiography uses penetrating radiation to record an image of the weld interior on film or a digital detector. For the exam, learn the purpose of an image quality indicator: it shows whether the technique was sensitive enough to see a flaw of a given size. Know why film density has limits, why location markers exist (so a flaw in the image can be found on the part), and why backscatter has to be controlled. Then connect it to the vessel: the type of radiography done on the welds decides the joint efficiency, which feeds required thickness. Our joint efficiency and radiography explainer shows that link.

Liquid penetrant (Article 6)

Penetrant finds flaws open to the surface in non-porous material. A liquid enters the flaw, the surface is cleaned, and a developer draws the liquid back out so the flaw shows. Study the order of steps, why surface cleanliness matters, why contaminants in the penetrant materials matter on some alloys, and what the records must show. Know the limit: it finds surface-breaking flaws only. Angle Beam walks through each step in how liquid penetrant testing works.

Magnetic particle (Article 7)

Magnetic particle finds surface and near-surface flaws in ferromagnetic material. A magnetic field is set up in the part and particles gather where a flaw disturbs the field. The exam scope is the yoke and prod techniques only. A yoke sets the field between its legs, and prods pass current through the part. Learn which flaw orientations each technique shows well, and that the method does not work on non-magnetic material such as austenitic stainless steel. Angle Beam explains why field direction decides what shows in how magnetic particle testing works.

Ultrasonic thickness (Article 23, SE-797)

This is the method behind most of the thickness readings in your corrosion rates. A probe sends sound into the metal and the instrument measures the time for the echo from the back wall. Study calibration on a known thickness, the role of couplant, what a rough or pitted surface does to a reading, and why metal temperature matters. Then tie it to the vessel work: readings at condition monitoring locations feed the corrosion rate. Our condition monitoring locations explainer covers that side. To practice the thickness arithmetic, Angle Beam has a free ultrasonic thickness calculator.

General requirements (Article 1)

These questions are mostly definitions and responsibilities. Know the difference between inspection and examination as Section V uses the words, who owns responsibility for what, why calibration is documented and what records are kept.

Where the points are

Two patterns are worth practicing.

1. Pick the method for the problem. Given a flaw type and material, decide which method fits. A surface crack in carbon steel suits penetrant or magnetic particle. A buried weld flaw needs radiography or ultrasonic work. Austenitic stainless steel rules out magnetic particle.
2. Find the right article fast. Part of this block can be open book. Practice going from a topic, such as image quality indicators or couplant, to the right article in your copy in under a minute. The open-book strategy guide shows how to build that map.

Keep the scope in mind. A page of Article 2 detail on film processing is outside what the Body of Knowledge asks for, while the scope and general rules are inside.

Next step

Take the free 10-question check at /api-510#q1 to see whether NDE is a weak domain for you. Then see the plans at /api-510/offer#plans, and ask Patch, the study buddy, at /study-assistant to quiz you on method selection with invented scenarios.

FAQ

Which Section V articles are on the API 510 exam?

The Body of Knowledge names Article 1 (general requirements), Article 2 (radiographic examination), Article 6 (liquid penetrant), Article 7 (magnetic particle, yoke and prod only) and Article 23 SE-797 (ultrasonic thickness measurement). It says the exam covers only the main body of each article, except where noted.

Do I need to know eddy current or acoustic emission for API 510?

No. The Body of Knowledge excludes NDE requirements for acoustic emission, eddy current and motion radiography.

Do I have to be able to perform NDE for the exam?

The Body of Knowledge asks you to be familiar with and understand the general rules for each method. The exam tests that understanding in the form of multiple-choice questions, not hands-on examination.

Is NDE open book or closed book?

Both parts of the exam can use it. The closed-book part covers everyday working knowledge, and the open-book part covers detail you would look up. Learn the purpose and limits of each method cold, and practice looking up the article details.

Sources

• API 510 Body of Knowledge, September 2026 to May 2027, American Petroleum Institute: sections I.B and III
• API 510 Pressure Vessel Inspector, American Petroleum Institute (exam structure and effectivity sheet)
• ASME BPVC Section V, Articles 1, 2, 6, 7 and 23 (SE-797), and Section VIII, Division 1 (UG, UW), cited by number only. Method descriptions are our own summaries.