Prepare for the American Welding Society Certified Welding Inspector (CWI) exams by separating fundamentals, practical inspection and code application. Use the three-part map, work the measurement example, and choose study materials that match your selected exam and reference format.
Who can apply for CWI?
The usual eligibility route is a high school diploma or equivalent plus five years of qualifying welding-based work experience. Submit the required education, experience and visual-acuity documentation.
AWS B5.1:2025 also describes other education and experience combinations. Relevant approved education can reduce the work requirement, but credit is limited and does not remove it. Check the table and supporting-document requirements for your own background rather than assuming any degree qualifies.
CWI is the American Welding Society welding inspector credential. Your construction or piping background does not create a different CWI syllabus, and a preparation course does not replace the eligibility requirements.
Official sources: Certified Welding Inspector (CWI) | AWS Certification Program — AWS certification landing page, retrieved 2026-09-14; CWI Examination User Guide (09.04.2026) — AWS examination user guide PDF; AWS B5.1:2025 — Specification for the Qualification of Welding Inspectors — Clause 6–8, education, experience, and exam structure
What should you expect in Parts A, B and C?
CWI requires at least 72% on each of the three parts. A high result on one part does not compensate for a result below that threshold on another.
Take Part B before Parts A and C. Part B is a practical inspection examination using supplied specimens and documents; you do not produce a live weld. Confirm the selected Part C form and its timing when you book.
| Part | Format and questions | Question time |
|---|---|---|
| A: Fundamentals | Closed-book computer test at Prometric; 165 total, including 150 scored and 15 unscored pretest items | 135 minutes |
| B: Practical | Paper examination at an AWS-authorized site using supplied inspection materials; 46 questions | 120 minutes |
| C: Codebook | Open-book computer test at Prometric; 50–60 scored, with 55–65 total on English forms containing pretest items | 135 minutes with pretest items; 120 without |
Official sources: CWI Examination User Guide (09.04.2026) — AWS examination user guide PDF; CWI Part A Fundamentals and Language-Assisted Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part B Practical Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part C Codebook Exam Information Guide — Certification Dept. Rev. 02.11.2025
What should you practise for each part?
Build a separate task list for fundamentals, practical inspection and code application. Use the current official content guides to check coverage.
The table summarizes the tested areas and suggests study tasks. NDE means nondestructive examination. Review the methods and their limitations using appropriate technical references; the study tasks do not replace the full content guides.
| Part | Areas to review | A useful study task |
|---|---|---|
| A | Terminology; welding and cutting processes; symbols; weld examination; welding application and control; NDE; heat control and metallurgy; calculations; inspector duties; destructive tests; safety | Explain a concept, interpret a symbol or work a calculation, then check the reasoning against an appropriate reference. |
| B | Inspection and discontinuity evaluation; procedure and welder qualification; mechanical tests and properties; NDE; specifications and drawings | Use the supplied practice specification and exhibits to identify the applicable criterion, units, evidence and decision. |
| C | Qualification; fabrication; inspection; reports and records; materials and design | Locate an applicable requirement and its exceptions in the approved reference for your chosen exam, then explain its application. |
Official sources: CWI Part A Fundamentals and Language-Assisted Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part B Practical Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part C Codebook Exam Information Guide — Certification Dept. Rev. 02.11.2025
Which study materials and codebook do you need?
Match materials to the exam part: fundamentals references for A, the public sample Book of Specifications for B, and the approved reference and edition for your selected Part C exam.
The Part A guide points to informative references for self-education rather than prescribing one study book. For Part B, practise with the public sample Book of Specifications and read the exam content guide. The exam provides its inspection materials, including exhibits, plastic replicas and an inspection tool kit.
Before buying a Part C reference, check the current Exam References and Editions Guide. For example, its D1.1 entry permits the 2020 or 2025 edition. Do not assume the newest edition of every other code is the one specified for your exam.
Some Part C exams provide an on-screen PDF and prohibit printed codebooks. Where paper is permitted, use an original publication or permanently bound printed copy with securely attached pages and bound errata. Check your selected exam’s rules and practise navigating the reference format it uses.
Official sources: CWI Examination User Guide (09.04.2026) — AWS examination user guide PDF; CWI Part A Fundamentals and Language-Assisted Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part B Practical Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part C Codebook Exam Information Guide — Certification Dept. Rev. 02.11.2025; AWS Exam References and Editions Guide — Last updated August 1, 2025
Practise applying a measured criterion
Write down the applicable limit, units and boundary wording before comparing each supplied value. State which criterion your result addresses.
This original paper exercise uses a fictional training rule. Its values are not AWS Book of Specifications or code limits, and the result does not establish overall weld acceptance.
Practice exercise
A fictional training worksheet supplies criterion T-7: a measured bead height must be from 5.5 mm through 6.5 mm, inclusive. Three exact measurements are supplied: specimen A = 5.4 mm, specimen B = 6.0 mm and specimen C = 6.5 mm. For each specimen, decide whether it meets T-7 and explain the boundary comparison.
Show answer
Specimen A fails T-7 because 5.4 mm is below the 5.5 mm minimum. Specimen B passes because 6.0 mm falls inside the 5.5–6.5 mm range. Specimen C passes because the criterion says 'not more than 6.5 mm inclusive,' so a measurement exactly at the upper boundary conforms.
Apply both bounds to each supplied value. A is below the minimum, B is between the bounds and C equals the permitted upper bound. Inclusive means the endpoints count. Record the measurement, units, criterion and result together. This checks only the invented T-7 criterion; a complete weld-acceptance decision would need the other applicable requirements and evidence.
Official sources: CWI Part B Practical Exam Information Guide — Certification Dept. Rev. 03.01.2024
How can you turn practice errors into a study plan?
Record the specific reason for each missed or guessed answer, then choose a short follow-up task that addresses it.
- Concept gap: revisit the relevant Part A topic and explain it in your own words.
- Reference gap: practise finding the applicable provision and exceptions in the correct Part B or C document.
- Calculation or interpretation gap: write the units, limits and comparison before deciding whether a supplied value meets the stated criterion.
- Timing gap: repeat a short set under timed conditions after you understand the answers.
- Coverage gap: compare your error log with all three content guides; repeated practice in one familiar area does not cover the other parts.
Official sources: CWI Part A Fundamentals and Language-Assisted Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part B Practical Exam Information Guide — Certification Dept. Rev. 03.01.2024; CWI Part C Codebook Exam Information Guide — Certification Dept. Rev. 02.11.2025
What should you check before applying?
Candidates in the US and Canada apply through AWS; candidates outside that area use an AWS Agent. Confirm the current application route, total price and required documents for your location.
Use the confirmation letter and eligibility codes to arrange the computer-based parts, and keep the required order of taking Part B first. Check appointment instructions for identification, arrival, permitted equipment and rescheduling.
CWI renewal falls at years three and six, followed by nine-year recertification. Review the current requirements and available recertification routes as your deadline approaches.
Official sources: Certified Welding Inspector (CWI) | AWS Certification Program — AWS certification landing page, retrieved 2026-09-14; CWI Examination User Guide (09.04.2026) — AWS examination user guide PDF
Official sources
Facts checked against AWS documents:
- Certified Welding Inspector (CWI) | AWS Certification Program
- CWI Examination User Guide (09.04.2026)
- CWI Part A Fundamentals and Language-Assisted Exam Information Guide
- CWI Part B Practical Exam Information Guide
- CWI Part C Codebook Exam Information Guide
- AWS B5.1:2025 — Specification for the Qualification of Welding Inspectors
- AWS Exam References and Editions Guide