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Free American Petroleum Institute (ICP) exam prep

Becoming an API 510 pressure vessel inspector: requirements, exam and preparation

Answer 10 questions weighted to American Petroleum Institute (ICP)'s published outline for your next exam, then see which domain needs the most work before you book.

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  • Scored by exam domain
  • Original questions only

Full courses from $199, with lessons, timed practice exams and a study plan. See the courses →

API 510 diagnosticExample report
I. Thickness measurements, inspection intervals and vessel integrity (calculations)78%
II. Welding procedure and qualification evaluation (ASME IX, RP 577)52%
III. Nondestructive examination (ASME V, VIII-1, API 510)66%
IV. Practical knowledge - general40%
Study first: IV. Practical knowledge - general

Illustration of the breakdown you get at the end. These are not real scores.

Built on American Petroleum Institute (ICP)'s outlineOriginal practice questions written to American Petroleum Institute (ICP)'s published content outline.
Original questions onlyEvery answer key is re-checked by a separate blind solve. Never real or recalled exam items.
Cite the code, don't copy itEvery explanation cites the code section or source it relies on. Bring your own licensed code copy.
Corrections in 2 business daysSpot a mistake? Tell us and we correct errors within 2 business days and log every change publicly.

The exam

Free API 510 diagnostic

Each diagnostic is weighted to that exam's published content outline, so your score breakdown matches what you will be tested on.

American Petroleum Institute (ICP)

API 510

API 510 Pressure Vessel Inspector
Questions
170
Time
390 min
Fee
Initial: 2026 $875 member / $1,125 non-member; 2027 $890 / $1,140. Late application $200. Reschedule (new window) $350

Free check: 10 questions, untimed, about 23 minutes.

Free diagnosticExam guide

Courses

The full courses

Lessons for every task, full-length timed exams and a study plan.

  • Available now · instant access

    API 510

    Learn every Body of Knowledge section, work the calculations step by step, then prove it on timed exams.
    • 8 modules of lessons
    • 2 full-length timed exams
    • 401 practice questions
    $199See the API 510 course

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API 510 certification from the American Petroleum Institute's Individual Certification Programs qualifies you as an authorized pressure vessel inspector. The exam is long and code-heavy. It runs for 390 minutes, with a closed-book part and an open-book part, and the open-book part gives you only the code sections listed on that window's Publications Effectivity Sheet.

Calculations decide a lot of results

The first section of the Body of Knowledge covers thickness measurements, inspection intervals and vessel integrity. That means corrosion rates, remaining life, inspection intervals, minimum required thickness, static head and MAWP. These calculations follow set methods, and getting the method right is most of the work. API doesn't publish section weights, so treat every section of the Body of Knowledge as fair game.

Pass rates are published

API publishes pass rates by exam window. For example, 64.0% of 1,167 candidates passed in the September 2023 window and 69.2% passed in January 2024 (API ICP statistics, April 2024). The exam guide links the source.

The exam in brief

  • Format: 170 questions (140 scored), with 110 closed-book and 60 open-book. Calculator and scratch paper are provided.
  • Where you test: in person at Prometric test centers during set windows. API 510 is not offered remotely.
  • Fees: $875 for members and $1,125 for non-members in 2026. An application is valid for 6 months from your first requested exam date, and after that it's a new application and the full fee again.
  • Experience: required before you can sit, and it depends on your education. See the guide.

Read the Body of Knowledge guide.

How to use Long Seam

  1. Take the free diagnostic: 25 questions across the Body of Knowledge, with no signup.
  2. Work the calculation types until you can set each one up without looking anything up.
  3. Read the effectivity sheet for your window and practice finding those sections fast.

Every question is original and written to the published API outline. They are never real or recalled exam questions, and we cite code sections by number only.

Guides and tools

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Exam guides

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Calculations and tools

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Career and certification

4 resources
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Updated 17 October 2026. Questions and guides are written by the Long Seam editorial team; see how we review them.