API 571 vs API 580 certification: exam format, bodies of knowledge, fees and windows beside API 510
API 571 Corrosion and Materials certifies that you know the damage mechanisms in API RP 571, and API 580 Risk Based Inspection certifies that you know risk-based inspection (RBI) as API RP 580 lays it out. Each is earned by passing one closed-book, multiple-choice exam of 3.25 hours, and each certification lasts three years. Here is how the two exams compare, what each one covers, what they cost and when you can sit them, from API's pages as read on 7 November 2026.
What API 571 and API 580 certify
API 571 is about corrosion and materials. API describes it as a check of your knowledge of corrosion processes, and its questions come from RP 571, Damage Mechanisms Affecting Fixed Equipment in the Refining Industry. If you can name a mechanism, say which materials and units it attacks, what drives it, what it looks like and how it is found and prevented, you are working in API 571's territory.
API 580 is about risk-based inspection. Its exam tests how an RBI program is set up and run under RP 580, Elements of a Risk-Based Inspection Program: assessing risk, collecting data, estimating probability and consequence of failure, and managing and documenting the result.
Put simply, API 571 asks what damage can happen to the equipment, and API 580 asks how to rank and plan inspection around that risk.
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The two exams side by side
| API 571 Corrosion and Materials | API 580 Risk Based Inspection | |
|---|---|---|
| Length | 3.25 hours | 3.25 hours |
| Questions | 110, of which 100 are scored | 90, of which 80 are scored |
| Unscored pretest questions | 10 | 10 |
| Format | Multiple choice, closed book | Multiple choice, closed book |
| What you can bring | No paper or reference materials | No paper or reference materials |
| Where | Test center or remote proctoring | Test center or remote proctoring |
| Built on | API RP 571, 3rd edition (2020) | API RP 580, 4th edition (2023) |
| Certification term | Three years | Three years |
Both exams are scored against a set passing scaled score, and API posts an exam tutorial to watch before test day. The question counts above are from API's API 571 and API 580 pages. The API 571 Body of Knowledge PDF linked from that page describes 110 scored questions plus 10 pretest, so check the count API gives you when you schedule.
With nothing on screen and nothing brought in, both exams test what you carry in your head. That is the biggest change from API 510, where part of the exam is open book.
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The bodies of knowledge
API 571. The Body of Knowledge is the whole of RP 571, 3rd edition (March 2020). API's Body of Knowledge PDF sorts it into two categories:
- Terms, definitions and acronyms
- Damage mechanisms, where for each one you should know its name, a description of the damage, the affected materials, the critical factors, the affected units or equipment, the appearance or morphology of the damage, prevention or mitigation, and inspection and monitoring
API 580. The Body of Knowledge is based on RP 580, 4th edition. The PDF for 2026 exams names the August 2023 edition with Addendum 1 (March 2025) and lists ten categories:
- Terms, definitions and acronyms
- Risk assessment
- The RBI program
- Roles, responsibilities, training and qualifications
- Data collection
- Damage mechanisms
- Probability of failure (POF)
- Consequence of failure (COF)
- Risk management
- RBI documentation
Damage mechanisms sit inside API 580 too, as one category of ten, so the two exams overlap there. Read each recommended practice in your own copy, by section.
Fees and windows
API's Schedules & Fees page puts API 571, API 577 and API 580 in one fee row:
| Fee | 2027 Fees: member / non-member | 2026 Fees: member / non-member |
|---|---|---|
| Initial certification | $390 / $450 | $380 / $440 |
| Recertification | $270 / $330 | $265 / $320 |
| Reschedule | $200 / $200 | $200 / $200 |
| Late application | $200 / $200 | $200 / $200 |
API 571 and API 580 test in the same windows as API 577 and API 936, three a year, each three weeks long:
| Window | Application deadline |
|---|---|
| 4 to 25 December 2026 | 2 October 2026 (passed) |
| 9 to 30 April 2027 | 4 February 2027 |
| 6 to 27 August 2027 | 4 June 2027 |
| 3 to 24 December 2027 | 30 September 2027 |
The next window you can still apply for is April 2027, so every window still taking applications tests in 2027.
To keep either certification, apply for recertification in API's ICP Portal from 90 days before it expires. API allows a 90-day grace period after expiry with late fees. Miss that and the certification lapses, and you need a new application, the fees and a pass on the full exam. API says employment verification is not currently required to recertify.
How they sit next to API 510 and 570
RP 571 is already on your API 510 or 570 sheet. The API 510 effectivity sheet for September 2026, January 2027 and May 2027 and the API 570 sheet for February and June 2027 both name RP 571, 3rd edition, and both limit it to Section 2 plus 15 mechanism paragraphs. API 571 takes the whole document, closed book. If you have learned the 15 mechanisms on the API 510 list, you have a start on API 571, and the pressure equipment damage glossary and the damage mechanism quiz are a quick way to see how well those 15 have stuck.
RP 580 is not. Neither of those two sheets lists RP 580, so API 580 is new reading for a 510 or 570 candidate.
Shorter and cheaper. Under API's 2027 Fees, the initial fee for API 510, 570 and 653 is $890 for members and $1,140 for non-members, against $390 and $450 for API 571 or API 580. The schedule page lists the 510, 570 and 653 exams at 7.5 hours each and API 571 and 580 at 3.25 hours.
Different windows. API 510 tests in January, May and September, and API 571 and 580 in April, August and December, so a 510 candidate won't face both in the same window. Our API 510 vs 570 vs 653 comparison sets out the three in-service inspector programs, and the API 1169 certification guide covers API's 3-hour pipeline construction inspector exam.
Long Seam prepares you for API 510 and API 570. It has no API 571 or API 580 course.
FAQ
What is API 571 certification?
API 571 Corrosion and Materials is API's certification in damage mechanisms. You earn it by passing a 3.25-hour, closed-book exam whose questions come from API RP 571, 3rd edition, and it lasts three years.
What is the API 580 exam?
It is the exam for API 580 Risk Based Inspection: 90 multiple-choice questions, 80 of them scored, in 3.25 hours, with no references allowed. It is built on API RP 580, 4th edition.
Is the API 571 exam open book?
No. Every question is closed book, and paper and reference materials are not allowed. The same is true of API 580.
How much do API 571 and API 580 cost?
Under API's 2027 Fees, initial certification is $390 for members and $450 for non-members for either exam. The 2026 Fees list $380 and $440. Recertification is $270 and $330 in 2027.
Can I take API 571 or API 580 remotely?
Yes. API says both exams can be scheduled at an in-person test center or through remote proctoring, during the regular exam windows.
When are the next API 571 and API 580 exams?
The next window still open is 9 to 30 April 2027, with applications due by 4 February 2027. After that come 6 to 27 August 2027 and 3 to 24 December 2027.
Do I need API 571 to pass API 510?
No. API 510 tests only the parts of RP 571 its effectivity sheet lists: Section 2 and 15 mechanism paragraphs for the September 2026 to May 2027 windows. API 571 is a separate certification on the whole document.
Studying for API 510 first?
Take the free 10-question API 510 check. It takes a few minutes, needs no signup and shows which Body of Knowledge domains to study first, damage mechanisms included, with every answer explained. The Long Seam course adds a lesson for each domain, timed practice exams and a study plan from your exam date.
Sources
Show the list
- API 571 Corrosion and Materials, American Petroleum Institute. Checked 7 Nov 2026.
- API 571 Body of Knowledge, American Petroleum Institute, linked from the API 571 page as the Body of Knowledge for 2026 exams. Checked 7 Nov 2026.
- API 580 Risk Based Inspection, American Petroleum Institute. Checked 7 Nov 2026.
- API 580 Body of Knowledge for 2026 exams, American Petroleum Institute. Checked 7 Nov 2026.
- ICP Schedules & Fees, American Petroleum Institute, "2026 Fees" and "2027 Fees" tabs and the 2026 and 2027 schedules. Checked 7 Nov 2026.
- API 510 Exam Publications Effectivity Sheet, September 2026, January 2027 and May 2027, American Petroleum Institute. Checked 7 Nov 2026.
- API 570 Exam Publications Effectivity Sheet, February 2027 and June 2027, American Petroleum Institute. Checked 7 Nov 2026.
Facts come from the sources listed above. If something has changed, tell us and we will correct it within 2 business days.
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