Which code book and which edition you need for the CWI exam
Quick answer
Which code book and edition do I need for the CWI exam?
The open-book portions of the AWS Certified Welding Inspector exam are administered to a specific edition of each code, and every endorsement pins its own edition. Buying the wrong edition is a common and expensive mistake. This dated table maps each endorsement to the exact edition AWS lists for the current exam window, checked against the official Exam References and Editions Guide.
The American Welding Society (AWS) administers the open-book parts of the Certified Welding Inspector (CWI) exam to a specific edition of each code, and every endorsement pins its own edition. The code books are your own purchase, and they are expensive, so buying the wrong year is a costly mistake people make often. The editions below are taken from the official AWS Exam References and Editions Guide, last updated August 1 2025, and were re-checked against the AWS pages on 2026-07-23. AWS can revise these when a new code edition is released, so confirm the edition on your own exam confirmation before you buy.
We publish which code and which edition each exam uses, because that is a fact. We never reproduce the copyrighted code text itself: that stays your own purchase from AWS, the American Petroleum Institute (API), or the American Society of Mechanical Engineers (ASME).
Endorsement code editions for the current exam window
| Endorsement | Code book | Edition AWS lists |
|---|---|---|
| Structural Steel (D1.1) | AWS D1.1 Structural Welding Code, Steel | AWS D1.1/D1.1M:2020 and :2025 (the exam is written to apply to either) |
| Structural Aluminum (D1.2) | AWS D1.2 Structural Welding Code, Aluminum | AWS D1.2/D1.2M:2014 |
| Bridge Welding (D1.5) | AWS D1.5 Bridge Welding Code | AASHTO/AWS D1.5/D1.5M:2020 |
| Railroad (D15.1) | AWS D15.1 Railroad Welding Specification | AWS D15.1/D15.1M:2019 |
| Aerospace (D17.1) | AWS D17.1 Fusion Welding for Aerospace Applications | AWS D17.1/D17.1M:2024 |
| Pipeline (API 1104) | API Standard 1104, Welding of Pipelines and Related Facilities | API 1104, 22nd Edition |
| ASME piping | ASME BPVC Section IX, ASME B31.1 Power Piping, ASME B31.3 Process Piping | Section IX 2023, B31.1 2024, B31.3 2024 |
The D1.1 line carries two editions because AWS states the structural steel exam is designed to apply to either the 2020 or the 2025 edition. If you already own the 2020 edition you do not need to re-buy for that reason alone, but confirm on your own exam confirmation.
The ASME piping endorsement pins three books at once
The combined ASME piping endorsement is the one that catches people out on cost, because it references three separate ASME publications, each a separate purchase: ASME Boiler and Pressure Vessel Code (BPVC) Section IX (2023), ASME B31.1 Power Piping (2024), and ASME B31.3 Process Piping (2024). The 60-question exam splits 26 questions on B31.1, 18 on Section IX, and 16 on B31.3. Budget for all three books, not one.
What Part B uses instead of a code book
The Part B practical is not a code exam. It is administered against the AWS Book of Specifications, a controlled document you use with a set of molded plastic weld replicas and inspection gauges at the test site. You do not buy a code edition for Part B; the Book of Specifications is provided for the exam. See the Part B practical walkthrough for what the kit contains.
Buy the book once, and buy the right year
The single most expensive edition mistake is buying last year’s API 1104 or an older D1.1 printing and discovering it on exam day. Confirm the edition against your own AWS exam confirmation letter, which lists the editions your specific exam is administered to, then buy. If you are still choosing an endorsement, the endorsement recommender maps your industry to the right code first, so you are not buying a book for an endorsement you did not need.
Source: AWS Exam References and Editions Guide (last updated August 1 2025) and the AWS CWI and SCWI endorsements pages, checked 2026-07-23. Editions can change when a code is re-issued; the date above is when each was last verified against the official source.