The Inspector's Role
The Welding Inspector's Role & Responsibilities
What a CWI actually does, the three exam parts, and the ethics that govern the job.
What a CWI Does
A Certified Welding Inspector verifies that welding is performed according to the applicable code, standard, or specification. The inspector's work spans three phases:
• BEFORE welding — review drawings and the WPS, check base metals, fit-up, joint preparation, and welder qualifications. • DURING welding — monitor preheat, interpass temperature, technique, and that the approved procedure is being followed. • AFTER welding — perform visual inspection, witness NDE, evaluate results against acceptance criteria, and document everything.
Inspection is about verification and documentation — not doing the welding yourself.
The Three Parts of the Exam
The AWS CWI exam has three parts:
• PART A — Fundamentals: welding processes, terms, symbols, metallurgy, and inspection principles (closed book). • PART B — Practical: hands-on with a 'Book of Specifications' and inspection tools, measuring and evaluating sample welds. • PART C — Code Book: open-book application of a specific code (such as AWS D1.1 Structural Welding Code — Steel).
You must pass all three parts.
Ethics & Responsibility
A CWI must act with integrity. Findings must be based on facts and the code — not pressure from the contractor or the schedule. The inspector reports what the evidence shows, accepts or rejects work against the written acceptance criteria, and never falsifies records.
The inspector's authority comes from the contract documents and the referenced code. If it isn't in the code or the specification, it isn't a valid basis for rejection.
📖 Key Terms
- WPS
- Welding Procedure Specification — the written document giving the variables for making a code-compliant weld.
- Acceptance criteria
- The standards a weld must meet to be accepted, defined by the applicable code.
- Code / standard / specification
- The documents that define the rules a weld must satisfy.
- Discontinuity vs. defect
- A discontinuity is any interruption in the weld; it becomes a defect only when it exceeds the acceptance criteria.
💡 Exam Tips
- ▸Inspection happens before, during, AND after welding — not just at the end.
- ▸A discontinuity is only a 'defect' when it exceeds the code's acceptance criteria.
- ▸Rejection must be based on the code or specification, never personal opinion or schedule pressure.
- ▸Know the three exam parts: A (fundamentals), B (practical), C (code book).