API 570 Open Book vs Closed Book: What to Memorize

What the two parts actually are

The exam day is 7.5 hours: a short tutorial, the closed-book part, a 45-minute lunch and the open-book part. Of 170 questions, 140 are scored and 30 are pretest questions you can't pick out, so treat every item as live.

API's Body of Knowledge describes the closed-book part as testing knowledge and tasks that call for everyday working knowledge of API 570 and its references. It describes the open-book part as using more detailed information that an inspector is expected to find in the documents but would not normally commit to memory. That one sentence is your study plan.

Papers, notes and books are not allowed in the testing center. During the open-book part, PDFs of the referenced publications appear on screen. API words which sections appear differently by program, so read the effectivity sheet guide and API's tutorial before exam day.

What to memorize for the closed-book part

At 1.5 minutes a question there is no time to open a mental index. Aim to own these cold:

• Corrosion rate and remaining life. The Body of Knowledge says the formulas for corrosion rate, remaining life and the interval rules may be closed-book. Know the long-term and short-term versions and when each applies.
• Definitions and roles. Inspector, owner/user, repair, alteration, rerating, condition monitoring location and similar terms.
• Damage mechanism vocabulary. For the RP 571 paragraphs on the list, be able to name the mechanism, the material at risk and where it shows up in piping.
• Inspection types and purposes. What each type of inspection is for, and what each NDE method finds.
• Welding basics. Essential versus non-essential variables, and the logic of a procedure qualification.

A practical test: if you would need more than 90 seconds to find it in a book, it belongs in the memorize pile. Write each item as a one-line prompt and drill it in short sessions. The closed-book exam guide has a drill built on the same format, written for vessels.

What to look up in the open-book part

The open-book part rewards detail you would not carry in your head: a table value, a limit, a paragraph that lists what a record must hold. Typical lookup work for piping includes flange ratings, thermal expansion between two temperatures, weld joint quality factors, impact exemption temperatures and test pressure factors. The Body of Knowledge names the sections for each.

Your skill here is routing. Ask three things in order:

1. Which publication holds this rule? (API 570, RP 574, RP 577, B31.3, B16.5, PCC-2 and so on)
2. Which section or table is it likely in?
3. Is a unit or a corrosion allowance hidden in the stem?

Drill it on your own copies with search disabled. Our open-book strategy guide lays out the full routine, and the Body of Knowledge article tells you which publications to build your tabs around.

A time budget with invented numbers

Say you sit the open-book part with 60 questions and 225 minutes. Here is one way to spend it:

• 40 questions you can route in about 2 minutes: 80 minutes
• 15 questions that need a calculation plus a lookup, about 5 minutes each: 75 minutes
• 5 hard ones you flagged, about 8 minutes each: 40 minutes

That adds up to 195 minutes, leaving 30 minutes to revisit flags and check units. If the same exam has you spending 6 minutes on every item, 60 items would use 360 minutes, which is 135 more than you have. That is why lookup speed is a trained skill, not a feature of knowing the material. The numbers are invented and personal; build your own from a timed practice block.

How to practice each part

• Closed-book blocks: 55 questions in 82 minutes is half of the closed-book part at exam pace. Work with a four-function calculator and no notes.
• Open-book blocks: 20 prompts of the form "where is the rule for X?" in 75 minutes, with a log of publication, section and minutes taken.
• Mixed blocks: shuffle both types in the last weeks, so you can change gears on the day.

Our dated plans, API 570 study plan before 26 November and the June 2027 study plan, place these blocks week by week, and API 570 practice questions gives three worked items to start from.

Next step

Take the free 10-question check at /api-570#q1 and note which misses were memory and which were lookups. Then see the plans at /api-570/offer#plans, and ask the study buddy at /study-assistant for a plan built around your exam date.

FAQ

Is the API 570 exam open book?

Partly. The closed-book part has 110 questions and allows no notes or books. The open-book part has 60 questions, and you use the PDFs of the publications that appear on your screen.

Can I bring my own copies of the codes?

No. API's page says papers, notes and books are not allowed in Prometric's centers. Your own copies are for studying, not for exam day.

How long is each part of the API 570 exam?

The closed-book part is 2.75 hours and the open-book part is 3.75 hours, with a 45-minute lunch between them. The whole day is 7.5 hours including a short tutorial.

Which part is harder?

That depends on you. Candidates who calculate often tend to feel faster in the closed-book part, and candidates who read codes often tend to feel faster in the open-book part. Time a block of each and compare your own numbers.