API570 Reference Materials: What You Can Use Open Book

What "Open Book" Actually Means on the API 570 Exam

When most people hear "open book," they picture flipping through dog-eared pages at a library table. The API 570 Piping Inspector examination works nothing like that. The open-book portion of the exam takes place entirely on a Prometric computer terminal, and every reference document is a PDF displayed through a viewer built into the exam software. You do not bring any paper, any personal notes, or any printed standards into the testing room.

Understanding this distinction early is not a minor administrative detail - it fundamentally changes how you should prepare. Candidates who spend weeks memorizing table values they assume they can "just look up" often underestimate how long it actually takes to locate a specific paragraph under exam pressure. Candidates who assume the PDFs will contain searchable text sometimes discover that certain figures or tables require manual scrolling. Both assumptions lead to the same outcome: running out of time in the open-book segment.

The full exam day is 7.5 hours. After a brief tutorial, you work through 2.75 hours of closed-book questions, take a 45-minute lunch break, and then return for 3.75 hours of open-book questions. That open-book window sounds generous until you account for 60 questions that each require locating relevant code language, reading it carefully, and selecting the defensible answer. That is roughly three and a half minutes per question if you spend zero time re-reading or cross-referencing.

The Official Reference Documents You Can Access

The exact documents permitted on any given exam sitting are defined by the Publications Effectivity Sheet that API publishes for each exam cycle. For 2025 and 2026 exam windows, candidates should download the current Effectivity Sheet directly from API's ICP website and verify every edition number before purchasing study materials. Edition mismatches are one of the most common and avoidable preparation mistakes.

With that important caveat in place, the core reference library for the API 570 exam consistently includes the following categories of documents:

Note that ASME Section II Part D (material properties and allowable stress tables) also appears on many exam sittings, particularly for questions that involve ASME B31.3 design calculations. Again, confirm the exact edition on the current Publications Effectivity Sheet - this is not something to guess at when the exam fee runs between $875 and $1,125 depending on API membership status.

How the PDF Interface Works at the Prometric Center

At a Prometric center, the exam interface splits your screen: questions appear on one side and the PDF viewer on the other, or you toggle between them. The viewer typically supports basic text search using Ctrl+F, but the reliability of that search depends on whether the document was scanned as a true text PDF or as an image. Some figures and appendices within ASME documents are image-based and will not respond to keyword searches.

This makes pre-exam familiarity with document layout arguably more valuable than any keyword searching shortcut. Knowing that ASME B31.3 Table A-1 lives near the front of Appendix A, that API 570 Section 7 contains the corrosion rate formulas, and that API 574 Section 6 covers threaded and socket-welded piping - all of this geographic knowledge in the PDFs saves irreplaceable seconds per question.

You can find details about exam windows and scheduling deadlines at the API570 Exam Schedule and Testing Locations 2026 page - knowing your exam date well in advance gives you time to acquire the correct document editions and build PDF navigation fluency before test day.

Domain 2: Open-Book Code Application - What It Tests

The exam's 170 total questions (140 scored, 30 unscored pretest) are split between two domains. Domain 2 - Open-Book Code Application - accounts for 60 questions answered during the 3.75-hour second half of the exam. These questions are deliberately structured to require code language, not just general knowledge.

What this means in practice: a Domain 2 question will not ask you to recall from memory what the maximum interval is for a Class 1 piping circuit. It will present a scenario - a specific fluid service, a measured corrosion rate, a calculated remaining life - and ask you to determine the correct inspection interval or required action under the code. The answer requires you to locate the governing paragraph, read the conditions and exceptions, and apply them to the presented scenario.

The open-book segment favors candidates who genuinely understand piping inspection work - people employed by authorized inspection agencies in petroleum refining or chemical process settings. That experience base is not accidental; the prerequisites for API 570 (built on the same education-plus-experience framework as API 510) are specifically designed to ensure candidates have seen the code applied in real operating situations before they sit for the exam.

Navigating the API 570 Standard Efficiently

Because API 570 (the standard) generates the majority of open-book questions, efficient navigation of that single document pays outsized dividends. The standard is organized logically, and candidates who internalize its section structure can move to the right area without relying on search alone.

Key structural landmarks to know cold:

• Section 3 - Definitions: when a question hinges on the exact meaning of a term like "corrosion circuit," "injection point," or "deadleg," this section is your first stop
• Section 5 - Inspection Practices: covers corrosion monitoring locations (CMLs), what requires more frequent inspection, and the special scrutiny areas like soil-to-air interfaces and insulated lines
• Section 6 - Inspection Intervals: the maximum allowable intervals organized by fluid service and risk classification, along with the risk-based inspection (RBI) pathway
• Section 7 - Thickness Measurement and Corrosion Rate Calculations: the short-term and long-term corrosion rate formulas live here; many candidates know these by heart but still confirm the exact form during open-book
• Section 9 - Repairs, Alterations, and Rerating: the authorization requirements, temporary repair limitations, and the role of the piping engineer in accepting permanent repairs
• Appendices - Contain supplementary guidance on RBI, leak testing, and condition monitoring that occasionally drives scenario questions

High-Value Sections Candidates Miss Most Often

Experienced piping inspectors sometimes over-concentrate on the sections they use daily on the job and underweight code areas they rarely encounter in their specific facility. The exam covers the full scope of in-service inspection across all piping circuit classes, fluid services, and repair scenarios - not just the narrow slice that any single plant deals with.

Sections and topics that consistently generate questions but receive insufficient study time include:

• Injection points and mixing points - API 570 Section 5 specifies heightened inspection requirements at these locations; exam questions often probe whether a candidate recognizes which physical configuration triggers additional CMLs
• Deadlegs and soil-to-air interfaces - both are explicitly called out as susceptible locations; understanding why (stagnant flow, accelerated external corrosion at grade) helps you apply the rule to novel scenarios
• Temporary repairs - the conditions under which a temporary repair is acceptable, the maximum duration, and what documentation the owner-user must maintain are all testable under Section 9
• Rerating calculations - ASME B31.3 maximum allowable operating pressure (MAOP) recalculation appears in open-book questions; candidates need to know both the formula structure and where to find material allowable stresses in Table A-1
• API 571 damage mechanisms - while API 571 is partly tested in the closed-book segment, scenario-based open-book questions will describe field observations (cracking pattern, temperature, material) and expect you to identify the mechanism and its controlling inspection method

Pair your PDF navigation practice with API 570 practice tests that mirror the scenario-based structure of real open-book questions. Answering a question under time pressure while simultaneously locating the governing code paragraph is a skill that only develops through repeated simulation.

Why Closed-Book Preparation Still Drives Your Score

A common strategic mistake: candidates spend the majority of their preparation time on open-book topics because those questions feel more approachable - "I can always look it up." But Domain 1 - Closed-Book Knowledge - contains 110 questions, which is nearly double the open-book count. Even though both domains contribute to a single scaled score, the closed-book segment has greater raw weight.

Closed-book questions test areas where reference documents are explicitly unavailable and where rote understanding is the only recourse. That includes:

• Damage mechanism identification (corrosion under insulation, stress corrosion cracking, hydrogen embrittlement, high-temperature hydrogen attack) - API 571 territory, entirely from memory
• NDE method capabilities and limitations - which technique detects surface-breaking versus subsurface flaws, sensitivity limits, material restrictions
• Inspector roles, responsibilities, and authority boundaries - what an owner-user authorized inspection agency inspector can and cannot authorize
• Weld procedure and welder qualification concepts (ASME Section IX) at a conceptual, non-lookup level
• Piping classification definitions and the criteria that determine circuit class

Approximately one-third of API 570 content overlaps with API 510 and API 653. Candidates who have recently sat for those exams may find certain closed-book topics familiar, but the piping-specific material - circuit classification, piping component inspection, injection point protocols - requires dedicated study regardless of prior certification history.

Allocating Your Prep Time Across Both Domains

Because the two domains require fundamentally different mental skills, they benefit from different study approaches scheduled at different points in your preparation calendar. The following framework is calibrated specifically to the API 570 domain structure - not generic exam advice.

The approximately 62% historical pass rate reflects the combined difficulty of both domains. Most unsuccessful candidates can identify, in retrospect, whether they underperformed on closed-book recall or ran out of time in the open-book segment. Honest timed practice before exam day eliminates that post-exam surprise.

Frequently Asked Questions