Coming sooniOS and Android

Pass the API 510 Pressure Vessel Inspector exam

614 original questions across all 11 Body of Knowledge domains, timed mocks that mirror the real two-section paper, and a predicted score that tells you when you are ready to book.

3 days free on the monthly plan, or £69.99 once for lifetime access.

Closed book · Question 4 of 1002:41

A vessel's measured wall thickness has fallen below the required minimum at one location. What governs whether it may stay in service?

A   The original design thickness
B   An engineering assessment of the affected area
C   The next scheduled inspection date
Every answer explained in full
614
practice questions
11
domains covered
170
questions per mock
100%
of exam weight

What you get

Six things the app does that a question dump does not.

Every answer is explained

Not just marked right or wrong. Each answer sets out why it is correct and why each other option is not.

Full timed mock exams

170 questions in two sections that mirror the real paper: 110 closed book in 165 minutes, then 60 open book in 225 minutes.

A predicted exam score

A live estimate of where you would land today, corrected for guessing and broken down by domain, so you know when to book.

Ten questions a day

An adaptive engine picks your daily set from the exam blueprint, your weak domains and what you have not seen lately.

Misses come back

Spaced repetition resurfaces a wrong answer at widening intervals until you get it right three times in a row.

Calculations step by step

Corrosion rate, remaining life, inspection interval, MAWP, static head, hydrotest pressure and weld sizing, broken into one operation at a time.

Every domain, weighted like the exam

The question bank follows the published Body of Knowledge, so the time you spend matches the marks on offer.

API 510 code45%
Calculations12%
ASME VIII Div 110%
ASME IX welding qualifications8%
ASME V non-destructive examination7%
Welding (API 577)5%
Damage mechanisms (API 571)5%
Pressure relieving devices (API 576)3%
Inspection practices (API 572)2%
Repairs (ASME PCC-2)2%
Material verification (API 578)1%

Weightings follow the certifying body's published Body of Knowledge for the current exam window. API 510 Prep is an independent study tool from Cyber Phoenix LTD and is not affiliated with, endorsed by or sponsored by any certifying body. All trademarks belong to their respective owners.

Pricing

One unlock. Everything in the app, on both platforms.

Most popular

Monthly

£14.99 / month

3 days free, then billed monthly. Cancel any time.

  • Every question and mock exam
  • Spaced review of your misses
  • Predicted score by domain
  • Works offline

Lifetime

£69.99 once

One payment. No renewal.

  • Everything in monthly
  • Every future question added
  • No subscription to cancel
  • Works offline

Common questions

How many questions are in the app?
614 original questions, written in-house and spread across all 11 Body of Knowledge domains in proportion to how the real exam weights them.
Does the mock exam match the real paper?
Yes. 170 questions in two sections: 110 closed book in 165 minutes, then 60 open book in 225 minutes. The domain mix follows the published blueprint, so the pacing and fatigue are realistic.
What is the predicted score?
A running estimate of the percentage you would score today, built from your answers and corrected for guessing. It is broken down by domain so you can see which one is holding you back. It is an estimate, not a guarantee.
Do I need to buy the standards to use the app?
No. Everything you need is in the app, including a full written explanation for every answer.
Is there a free trial?
Yes, three days free on the monthly plan. There is also a one-off lifetime option if you would rather not have a subscription.
Does it work offline?
Yes. The question bank is on your device, so practice, mocks and review all work without a connection.

Start with the placement test

Twenty minutes to find out where you actually stand across every domain, before you spend a single study session on the wrong one.