What to study to pass the api 653 examination

By Carlos F Molina

Choosing to read this article is choosing to begin the path to API certifications. The most important objective of apiexam.com is to give affordable, safe learning advice in order for you to pass the API certification examinations, beginning now, and not having to make the course and spend the bunch of money it costs.

The way I see it, if you already decided you want to try certification, you have 4 options…..

Study on your own beforehand, don´t take the course then take the exam

Not recommended. Maybe you are one of those people that can read English very well, and are used to taking and passing tests of all kinds.  However, have in mind that there are several differences and correlations between API 650 and 653 that are not so clear to see, so you will need someone´s guide to really understand what you are studying

Study on your own beforehand, then take the course then take the exam

This is highly recommended, especially if you are already using the standards on a daily basis, if you have experience in the field or any certification in welding or NDE.

Don´t study beforehand, then take the course then take the exam

Not recommended if you are not using the standards on a daily basis. As you know, learning is a lot easier when you build up new concepts above old concepts you have. However, Is not just knowing and not studying, given that standards are of changing nature. I know several people that are experts in the field of tanks, but as they are not used to taking tests, or they don´t understand English well, they flunk the exam.

Take the course and don´t take the exam

This is a big mistake. Ideally, you should try to take the exam immediately after you have taken the course, so the concepts are still “hot” in your mind. The craziest mistake you can make is taking the course and not the exam, because, let´s face it, it is certification what we are talking about. Certification opens new doors. Taking the course and flunking is not precisely comfortable to say.

So what is this website for? To give students a possibility to have contact with the standards on a daily basis, by means of Questions and Answers, Exercises, Examples, Animations, etc. My aim here is to make it so good that you won´t even have to take the course. Are you up to it?

This is what you should learn from API 653 in order to pass the exam


API regularly launches a Body Of Knowledge (BOK), that summarizes the core teachings, concepts, and essential competencies that need to be mastered by new inspectors to receive certification. API 653´s body of knowledge is dynamic, since every year it incorporates new information and techniques. The current Body Of Knowledge was updated as of October 2013.

According to the current BOK, to be a successful inspector you will need to know the following:

  How to evaluate corrosion rates and inspection intervals
  Establish joint efficiencies
  Calculate maximum Fill Height for an Hydrostatic test
  Determining the sizes and spacing of welds for shell openings
  Determining requirements for Hot Tapping
  Settlement evaluation
  Number of settlement points
  Impact Testing
  Calculate minimum thickness of tank shell
  Calculate minimum thickness of tank shell for reconstructed tanks
  Determine if a tank shell corroded area is acceptable for continued service
  Evaluate a pitted area
  Calculate dimensions for replacement plates
  Calculate dimensions for lap welded patch plates
  Ensure you can proficiently review a PQR and a WPS and determine it’s conformance to Sec IX
   See #1
API 650 AND 653
  General welding requirements
  Be familiar with and understand NDE applied to tank repair and construction
API 650 AND 653
  General NDE requirements
  API RP 571, Damage Mechanisms Affecting Fixed equipment in the Refining Industry
  API Recommended Practice 575, Inspection of Atmospheric and Low-Pressure Storage Tanks
  API RP 577, Welding Inspection and Metallurgy
  API Standard 653, Tank Inspection, Repair, Alteration, and Reconstruction and the relatedportions of API Standard 650, Welded Steel Tanks for Oil Storage
  API Recommended Practice 651, Cathodic Protection of Aboveground Petroleum StorageTanks s
  API Recommended Practice 652, Lining of Aboveground Petroleum Storage Tank Bottom

Just study that, and you should do fine

One of the resources you can take advantage of is the API 653 Questions series of articles that are outlined below.

1. Beginning the path: API 653 Questions

2. General and definitions. #2 in the API 653 questions series.

3. In the core of API 653. Path # 3.

4. Damage mechanisms for API 653 inspection. Path #4

5. Corrosion Under Insulation CUI (for exam takers). Path #5

6. Microbiollogically Induced Corrosion. Path #6

7. ASME V General questions. Path #7

8. ASME V, Article 23, SE-797. Path #8

9. Soil and caustic corrosion: Damage Mechanisms


Since 2012, there is a change in the way the exam is being held. Before that, you would go to a Prometrics place with your hard copy standards that would be checked and take a paper written exam. But now, the exam is administered via a computer in a Prometric´s testing center.( That means that you will save some dollars on standards)

The examination consists of two parts. The closed book part tests the candidate on knowledge and tasks requiring everyday working knowledge of API Standard 653 and the applicable reference documents. The open book portion of the examination requires the use of more detailed information that the inspector is expected to be able to find in the documents, but would not normally be committed to memory.

There are 150 questions on the exam, of which only 125 are scored. The remaining 25 are pretest questions.    The exam day is 8.5 hours long, and includes 3 hours for the closed-book section, 4 hours for the open-book section, a half-hour tutorial session, and a 1-hour lunch break.

Papers and books are not allowed in Prometric’s computer testing centers.  All materials needed for the open-book portion of the exam will be displayed on your computer screen in English.

One final tought


In some websites advertising training courses, they rest importance to memory as an important tool in learning technical subjects like standards. I think they are wrong, because people learn mostly building above what they already know. There is no learning without memorization. In fact, the Body Of Knowledge states clearly that the fact that there is an open book and a closed book part is because while there are some facts you need to use daily (closed book), so there are things that you won´t remember easily without opening the book.

With that in mind, I never discourage anyone to learn trough flash cards if they feel is the best option for them. If you keep coming back to API exam, you will see how we use flash cards and other tools to make study of API 650 and 653 very dynamic.

Again I thank you dearly for your support and the success of apiexam.com. Thank you, and good luck! Cheers!

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{ 24 comments… add one }
  • Navaneethan Sundaram January 24, 2015, 5:38 am

    I will be appearing for API-653 exam during March 2015.

    So please send me current API-docs and guide nme how start the Tank Inspection

    • imageniero@gmail.com January 24, 2015, 2:31 pm

      Hi Mr. Navaneethan.
      One advice that I can give and that everyone should take is: read the standards in order to understand them . When I had my exam, I really lacked experience, and altought I got 100MB of questions and answers, I trusted more in my own reading than anything else. Of course, some of the questions that appear in any practice test have appeared before and are likely to show up again in the future. Then the best advice is to read the standards. Regarding documentation, in this post you are commenting you can find all the documents I´ve created, as I create the documents as I study. Thanks.

      • Omokhoa Prophet January 23, 2017, 8:42 am

        Ghana is also another country

  • Adnan Ahmad May 3, 2015, 9:04 am

    Hi to Every one,

    I want to be appear for API 653 exam. I have practical experience of API 650 code application on daily basis. Now i need your people help that how i can prepare myself for this exam.I am average in English language.
    Your valuable advise will be helpful for me.

    • imageniero@gmail.com May 3, 2015, 11:22 am

      Welcome Mr Adnan. Feel free to browse all the site, or you could join the mail list in the about page, to receive the articles as they are published. Thanks

  • Bhavesh June 12, 2015, 5:47 pm

    Please send me api 653 related question bank

    • imageniero@gmail.com June 13, 2015, 9:58 pm

      There is already a question bank in this link, in this same website

  • Belief July 20, 2015, 6:03 pm

    What sort of opportunities does acquiring API 653 certification can give me. I’m an Engineer and I’m looking for something to further up my career. Regards

    • imageniero@gmail.com July 21, 2015, 10:29 am

      Hi. As an certified API 653, I´ve been asked to generate written contracts for the most important oil company i my country (I declined, though, because of family reasons). In fact, every repair contract of a tank here has the requirement of an API 653 certified person in the company making the repair. I think this kind of certifications works well for people looking to work in refineries and big chemical plants, as there are always integrity issues. I also receive many calls by a lot of other engineers when they are repairing tanks. That´s a summary.

  • ragesh July 24, 2015, 10:14 am

    Hai to everyone,
    I would like to attend API 653 exam on November 2015,please give valuable advice about how to prepare for the exam,which one is better self study or taking a course

  • Brian September 26, 2015, 7:55 am

    Hey, registered a week or so ago, Im taking my 653, was hoping to get the practice software, but havent heard anything back aftrer I registered

  • Bashu November 23, 2015, 2:29 pm

    If you have any idea regarding API 653 certification exam listed below, Please share
    a) Number questions to be asked under open book section .
    b) Approx. weightage on Marks Distribution. Weightage % in 653, 650, ….577 etc
    c) Number of questions (approx) related to Calculations.
    Thank you for your effort.
    With Regards,

  • Ahmed Fadoul January 20, 2016, 9:15 am

    I have only three moths on tank repair and Iwant tohave API 653 certificate ,your advise is much appreciated

  • Omokhoa Prophet April 13, 2016, 1:23 pm

    Do you have any AFRICAN Countries i can take this exam and certification?

    • Carlos F. Molina April 21, 2016, 12:10 pm

      No, I don´t have that information. API doesn´t have it in its web page.

    • Belief January 22, 2017, 7:08 pm

      Republic of South Africa.

  • murali May 26, 2016, 3:57 am

    Hello Everyone,
    I have not much experience in tank inspection but my company register 653 course ,I worry about the exam ,my English level is very average only ,the course start on Nov 2016 so please give your valuable advice for to prepare for the exam

  • sakthivel August 11, 2016, 3:25 am

    Sir, I am 15 years in storage tank construction. Now I want to study API 653 coming season. I tried to download the API application form But it is not downloaded.please help me in the matter.

    • fahad Ahmad November 19, 2016, 7:36 am

      you can do every thing online. go to the website and process your application there. They will ask you about the references which are needed to be true as they will send an official email to those references in order to make sure that the information given is not false. secondly u have to pay the exam fee upon the completion of the application form.you will get a confirmation email once your application is accepted.

  • Satnam Singh September 29, 2016, 6:32 am

    I need more Details / attention towards API 650 and 653

  • fahad Ahmad November 19, 2016, 7:31 am

    helloevery one? i just wanted to know about the meaning of the term “Marginal” that appears on the test screen right after the exam is over. is it a pass or fail??

  • Juan Sebastian Gomez January 22, 2017, 2:51 am

    Hi, Carlos. Excellent website, it has been all a discovery to me. I expect to take de API 653 exam this year and my first step will be to surf this pages.
    Kind Regards

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