clause5.io/ Welding/ CWI Exam Prep

Exam Structure: Three Parts

The CWI certification exam, administered by AWS per B5.1, consists of three independently scored parts. All three must be passed — either in a single sitting or across multiple attempts within the allowed window.

Part A — Welding Fundamentals

Format: 150 multiple-choice questions, 3 hours. Closed book.

Part A covers the theoretical foundation of welding inspection. Topics include welding metallurgy (phase diagrams, heat-affected zone, grain structure), welding processes (SMAW, GMAW, GTAW, FCAW, SAW — principles, advantages, limitations), weld defects and discontinuities (types, causes, acceptance criteria), NDE methods (VT, RT, UT, MT, PT — principles and capabilities), welding symbols per AWS A2.4, safety practices, destructive testing methods, and basic math (unit conversions, area calculations, heat input formulas).

Part A is where most candidates spend the majority of their study time. The WIT (Welding Inspection Technology) manual published by AWS is the standard study guide — it maps directly to the Part A content outline.

Part B — Practical Application

Format: 46 questions, 2 hours. Closed book (scenario materials provided in the exam booklet).

Part B tests the candidate’s ability to apply inspection knowledge to realistic scenarios. The exam provides drawings, WPS excerpts, inspection reports, and photographs of weld discontinuities. Candidates must read welding symbols from drawings, evaluate discontinuities against acceptance criteria, determine if WPS parameters are within limits, and make accept/reject decisions.

Part B is often considered the most challenging because it requires integrating knowledge from multiple areas simultaneously — reading a drawing, understanding the WPS, identifying the discontinuity, applying the correct acceptance criteria, and making a defensible decision under time pressure.

Part C — Code Book Exam

Format: 46 to 60 questions (varies by endorsement), 2 hours. Open book — bring your own code.

Part C is endorsement-specific. The most popular endorsements are:

The key to Part C is fast navigation. The questions are answerable from the code — the challenge is finding the answer within the time limit. Tab your code extensively with labeled sticky notes. Know the structure: which clause covers WPS requirements, which table has acceptance criteria, where the welder qualification rules are. Candidates who memorize the table of contents outperform those who try to memorize content.

Recommended Study Plan

Months 1-2: Part A fundamentals. Read the WIT manual cover to cover. Take notes on each chapter. Focus on the topics you are weakest in — for welders, that is typically metallurgy and NDE theory. For engineers, it is typically process details and practical defect recognition. Take practice exams weekly to identify gaps.

Month 3: Part C code book. Read your endorsement code from beginning to end. Build a tab system with labeled sticky notes for every major table, clause, and figure you will need to reference. Practice finding specific answers under time pressure — set a timer for 2 minutes per question. Common Part C topics for D1.1: Table 8.1 acceptance criteria, Table 5.5 essential variables, Clause 6 welder qualification, Table 5.7 filler metal matching, and Table 5.11 preheat requirements.

Month 4: Part B practical + review. Practice with scenario-based questions. The AWS prep course materials include Part B practice problems. Focus on the workflow: read the drawing, identify the weld type and symbol, check the WPS parameters, evaluate the discontinuity against the applicable acceptance criteria, make the call. Revisit weak areas from Part A practice exams.

Common Pitfalls

Under-preparing for the open-book Part C. Candidates assume they can look everything up during the exam. But with ~60 questions in 2 hours, that is only 2 minutes per question — not enough time to search the entire code. You need to know WHERE the answer is before you open the book. Tab extensively.

Skipping the math. Part A includes heat input calculations, unit conversions (inches to mm, psi to MPa), and area calculations. These are free points for candidates who practice — and lost points for those who skip math review.

Ignoring welding symbols. AWS A2.4 welding symbols appear in all three parts. Part A tests symbol identification, Part B provides drawings with symbols that must be read correctly, and Part C may reference symbol requirements in the code. Candidates who cannot read symbols quickly will struggle across all three parts.

Not taking practice exams under timed conditions. Knowing the material is necessary but not sufficient. The CWI exam is time-pressured — particularly Parts B and C. Candidates who practice under realistic time constraints perform significantly better than those who study without timing themselves.

Key Takeaways

• Study order: Part A first, Part C second, Part B last. Fundamentals build the foundation for both code navigation and practical application.
• Tab your code book extensively for Part C. Fast navigation beats memorization. Know the table of contents by heart.
• Practice under timed conditions. The exam is time-pressured — 2 minutes per question on Parts B and C. Untimed practice gives false confidence.
• First-time pass rates are estimated at 25-40%. Adequate preparation takes 3-6 months at 10-15 hours per week. The AWS seminar is a review, not a substitute for self-study.

"The CWI exam does not test whether you can memorize D1.1. It tests whether you can find the right clause, apply it to a real scenario, and make a defensible accept or reject decision under time pressure."

D1.1:2025 Clause 8.1 defines the visual inspection acceptance criteria that CWI candidates must know — Table 8.1 is the most-referenced table on the exam

Reference data from AWS B5.1:2013 and AWS QC1. Not affiliated with AWS.