AI Certification

What the AI Certification Actually Is

The Authorized Inspector (AI) Commission is a National Board credential for people who inspect boilers and pressure vessels during construction and in service under the ASME Boiler and Pressure Vessel Code framework. It is governed by The National Board of Boiler and Pressure Vessel Inspectors. If you landed here wondering about a different credential that shares the same two letters, this article is not about it. For a plain-language orientation, see What Is AI Certification? and What Does AI Stand For?.

This is a code-and-quality-system credential. You are not being tested on abstract theory. You are being tested on whether you can read the construction codes, understand what a manufacturer must do at each stage, and recognize where an inspector's duties begin and end. That orientation shapes everything about how you should prepare.

Exam Format and What Is Verified

The issuer's examination information confirms that the examination contains 85 questions and that candidates attend the AI Commission course and pass an examination. That is the extent of what can be stated with confidence here. The exact timer, the current fee and the numerical pass mark are not verified in this article, so confirm them directly with the National Board before you plan your budget or schedule. Our breakdowns of AI Certification Cost, the AI passing score and AI exam dates track what can be established and flag what cannot.

The absence of published weights is important. You cannot reverse-engineer a study plan from percentages, so you need to cover all 12 headings and lean on your own diagnostic results to decide where to spend extra hours. Eligibility and prerequisites are covered separately in AI Requirements.

The 12 Content Areas at a Glance

The detailed NB-331-NC outline has 12 numbered headings. The introductory 11-objective summary groups the content differently, but it does not replace the detailed hierarchy, so use the 12-heading structure when you build notes. A fuller walkthrough lives in AI Exam Domains: Complete Guide to All 12 Content Areas.

1. Responsibilities and Duties of the AI
2. Boiler and Pressure Vessel Types and Terminology
3. Code Structure and Content
4. Quality Control System
5. Design
6. Materials
7. Fabrication
8. Nondestructive Examination
9. Testing and Heat Treatment
10. Calibration of Measurement and Test Equipment (M&TE)
11. Data Reports and Stamping
12. Record Retention

Where the Code Reading Gets Dense

Domain 3: Code Structure and Content

This domain asks you to navigate the structure of the ASME Boiler and Pressure Vessel Code and its related requirements. The skill being tested is partly retrieval: knowing which Section governs a given construction type and where within it to look. Candidates who treat the codes as a single undifferentiated book tend to lose time on questions that a clear mental map would answer quickly.

Domain 4: Quality Control System

The outline points to three specific locations: Section I Appendix A-301, Section IV Appendix F and Section VIII Division 1 Appendix 10. These are the quality control system requirements for power boilers, heating boilers and pressure vessels respectively. Learn what each requires of a manufacturer and, just as importantly, what the inspector verifies.

Domain 5: Design

Design is broad. The outline covers power and heating boilers, external piping and vessels, and a long list of topics.

• Shells and drums, piping, headers and nozzles
• Formed and flat heads
• Braced and stayed surfaces
• Weld sizes and nozzle reinforcement
• Preformed and prefabricated pressure parts
• Flanges, joint efficiencies and ligament efficiency

Domain 6: Materials

Materials covers the construction-section rules, product-form tolerances, markings and methods, pressure and nonpressure parts, non-ASME standards, defective-material repair and certifications. The common thread is traceability: can you confirm that the material in the shop is the material the code and the drawings call for, and that its documentation supports it?

Fabrication and Welding: The Detail Trap

Domain 7, Fabrication, is where the outline gets the most granular, and it is where many candidates feel the volume of detail. It spans two clusters.

Because Section IX underpins the qualification questions, make sure you can follow how a welding procedure and a welder's qualification relate to the work being inspected. If you are weighing how demanding this material is overall, How Hard Is the AI Exam? discusses where candidates typically struggle.

NDE, Testing, Calibration and Records

Domain 8: Nondestructive Examination

Expect questions on when NDE is required, which methods are permitted, the advantages and limitations of each method, procedure and personnel qualification, and reports. Section V is the anchor reference. The practical skill is matching a method to a flaw type and knowing the qualification and documentation expectations that follow.

Domain 9: Testing and Heat Treatment

This heading combines impact testing, heat treatment and pressure tests, including exemptions and alternatives. Exemptions are a favorite source of tricky questions, so pay attention to the conditions under which a requirement does not apply and what may be done in its place.

Domain 10: Calibration of Measurement and Test Equipment (M&TE)

Calibration covers frequencies, methods, tolerances, master standards, identification and records for working and master measurement and test equipment. It is a smaller topic area, but it is self-contained and highly learnable, which makes it an efficient place to secure points.

Domains 11 and 12: Data Reports, Stamping and Record Retention

Data reports and stamping are specific to the construction type, so learn the report and stamp expectations separately for power boilers, heating boilers and pressure vessels. Record retention then follows the rules in Sections I, IV and VIII. Both domains reward organized, side-by-side comparison tables of the three construction types.

The Required Reference Library

The outline names the documents you are expected to work from. Treat this as your actual reading list.

Working directly with these documents, rather than only with summaries, is the single biggest differentiator for this credential. For a condensed memory aid once you have done that reading, see the AI Cheat Sheet, and use the AI Study Guide for broader planning.

Sequencing Your Preparation by Domain

Generic scheduling advice matters less here than ordering the domains sensibly. A logical build moves from vocabulary, to the code map, to the quality system, and only then into the granular construction rules. Adjust the pacing to your own background and the length of your course.

Fabrication is placed in the third week because it depends on materials and design knowledge, and because it is the densest block. If your diagnostics show a weak area, move it earlier rather than leaving it for the end. You can find practice questions mapped to these areas at our main practice test site, and the AI pass rate article explains why published figures should be treated cautiously.

Who Employs Commissioned Inspectors

Commissioned inspectors typically work for authorized inspection agencies, including jurisdictional programs and insurance-company inspection organizations, and for the organizations that need independent verification of code compliance on pressure equipment. Manufacturers of boilers and pressure vessels interact with inspectors constantly, so familiarity with their quality systems is valuable across the industry. For a realistic view of the roles, read AI Jobs. For earnings context without invented figures, see the AI Salary Guide, and weigh the whole picture in Is the AI Certification Worth It?.

Frequently Asked Questions