API 510 and 570 Exam Day: What Happens, Hour by Hour
What really happens on API 510 and 570 exam day: the 7.5-hour schedule, closed- and open-book pacing, what you can bring, scaled scores and results.
EIM Editorial Team15 Oct 20265 min read
Months of study come down to one long day in a test centre. Knowing exactly how that day runs removes a surprising amount of stress, and it changes how you should practise. This guide walks through the API 510 and API 570 exam day from booking to results, using API's own exam pages, checked 7 October 2026.
Short answer: The day lasts 7.5 hours at a Prometric test centre: a short tutorial, 2 hours 45 minutes of closed-book questions, a 45-minute lunch, then 3 hours 45 minutes of open-book questions with the codes provided as PDFs on screen. There are 170 questions, of which 140 are scored. Prometric emails a score report within 24 hours.
The day at a glance
| Part | Time | Questions | References |
|---|---|---|---|
| Tutorial | Short | None | How the testing software works |
| Closed book | 2 h 45 min | 110 | None |
| Lunch break | 45 min | ||
| Open book | 3 h 45 min | 60 | Listed code sections as PDFs on screen |
| Total | 7.5 hours | 170 (140 scored) |
The 30 unscored questions are pretest items API is trialling for future exams. They are mixed in with the scored ones and you cannot tell which is which, so treat every question as if it counts.
Before the day
- Get your eligibility and book early. Once API approves your application, you receive an exam authorisation with an eligibility ID and book your seat with Prometric. Seats are limited and fill by order of booking.
- Check the delivery mode. API's 510 page states the exam is given in person at designated test centres only. Check your own exam's page, since programmes differ.
- Watch API's exam tutorial for your programme. It shows the screens, navigation and how the PDFs open.
- Re-read the effectivity sheet for your window. The open-book PDFs are the editions on that sheet, not whatever is on your shelf.
- Sit one full rehearsal. Same start time, same 2 h 45 min and 3 h 45 min blocks, same 45-minute lunch. Stamina is part of the test.
At the test centre
Prometric centres run strict security. API's pages are clear that papers, notes and books are not allowed in the room. Bring the identification your Prometric confirmation asks for, arrive early, and expect to leave personal items in a locker. The codes you need for the open-book part are provided on screen, and a calculator is provided by the testing system.
The closed-book part: speed and certainty
110 questions in 2 hours 45 minutes is about 90 seconds each. These questions test what you should know without looking it up: definitions, inspection practices, damage mechanisms, the responsibilities of the inspector and the owner-user.
- Go through once, answering everything you know. Flag anything you are unsure of and move on.
- Come back to the flags with the time left. A fresh look often settles them.
- Never leave a question blank. There is no benefit to leaving it empty.
The open-book part: navigation, not reading
60 questions in 3 hours 45 minutes sounds generous, at about 3.75 minutes each. It is not, if you have to search unfamiliar PDFs for every answer. Calculations, tables and specific requirements live here: corrosion rates and remaining life, minimum thickness, pressure tests, weld and NDE requirements.
- Answer from memory first wherever you can, and save the PDFs for the questions that need them.
- Know the structure of each document: which section holds intervals, which holds repairs, where the tables are. The table of contents is your map.
- Practise on PDFs, not on a tabbed paper copy. That is how you will use them on the day.
- Check units and inputs before you calculate. Many wrong answers are right maths on the wrong number.
For the corrosion-rate and remaining-life arithmetic, see our worked examples in Corrosion Rate and Remaining Life.
Results and what happens next
Prometric emails a score report within 24 hours, and you can also view it on Prometric's score report site. Scores are scaled: Prometric reports on a 200 to 500 scale used across API's programmes, and API equates exam forms so the number of correct answers needed can differ slightly from one form to another. Final results reach your API ICP portal, and from there you can print your certificate and wallet card.
If the result is not what you wanted, write down the topics that felt weakest while the day is fresh. That note is worth more than any score breakdown when you plan the next attempt.
Five exam-day mistakes
- Studying the wrong edition. Always match your books to the effectivity sheet for your window.
- Spending ten minutes on one closed-book question. Flag it and keep moving.
- Looking everything up in the open-book part. You will run out of time.
- Never practising a full day. Fatigue in the final hour of the open-book part costs marks.
- Arriving late or with the wrong ID. Read your Prometric confirmation the night before.
Preparing with EIM
EIM is an independent training provider; API certifies inspectors, and EIM helps you prepare. Our exam pages explain API 510, API 570 and API 653 in full. For API 653, EIM's self-paced preparation includes a question bank, practice mode with explanations, timed mock tests, study notes, flashcards, a readiness score and a study plan worked back from your exam date, with one year of access. If you are sitting API 653 in 2027, read what changed in the codebooks first.
Frequently asked questions
How long is the API 510 exam?
The exam day is 7.5 hours: a short tutorial, 2 hours 45 minutes closed book, a 45-minute lunch and 3 hours 45 minutes open book.
How many questions are on the API 510 and 570 exams?
170, of which 140 are scored: 110 in the closed-book part and 60 in the open-book part.
Can I take my own code books in?
No. Papers, notes and books are not allowed. The listed code sections are provided as PDFs on screen for the open-book part.
How soon do I get my result?
Prometric emails a score report within 24 hours. The final result is then recorded in your API ICP portal.
What is the passing score?
API uses scaled scores on a 200 to 500 scale and equates different exam forms, so there is no fixed number of correct answers. Check API's scoring information for your programme.
