IIW IWI-C study guide
IIW IWI-C · Work through your exam, one topic at a time.
The International Welding Inspector Comprehensive (IWI-C) is the highest of the three IIW inspector qualifications, sitting above the Standard and Basic levels. It is aimed at engineers and senior inspection staff who already understand welding processes and want responsibility for procedure qualification, inspection planning, defect acceptance decisions and the contractual side of welded fabrication. The IIW IWI-C study guide has 8 sections and about 2,723 words.
01Welding Processes and Equipment
This domain tests whether you can choose a process for a joint, material and production context and defend the equipment settings from first principles. Expect quantitative items on power-source characteristics, duty cycle, deposition rate, heat input and process efficiency.
351 words, about 2 min02Materials and Their Behaviour During Welding
This domain tests metallurgical reasoning: why a joint cracks, what happens in the heat-affected zone (HAZ), and which consumable, preheat or interpass control reduces risk. For carbon-manganese steels the IIW carbon equivalent is CE = C + Mn/6 + (Cu + Ni)/15 + (Cr + Mo + V)/5, in wt%.
339 words, about 2 min03Construction and Design of Welded Structures
This domain tests whether you can read a welded detail as a designer does: load path, joint type, weld size, symbol and failure mode. Static strength and fatigue are both examinable, and ISO 2553 symbols are assumed knowledge.
351 words, about 2 min04Fabrication, Welding Procedure and Welder Qualification
This domain tests the qualification chain and the responsibilities attached to it: preliminary WPS, procedure qualification record, WPS, welder qualification and production control. ISO 15614-1 is a common route for procedure qualification of steels: a pWPS is used to make a test piece, which is tested to produce a WPQR; the WPS is then written from the qualified range.
342 words, about 2 min05Inspection, Testing and Quality Assurance
This domain tests how inspection is planned and evidenced, not just how a single test is performed. The exam expects you to link the inspection and test plan (ITP) to specification requirements, hold points and records.
340 words, about 2 min06Non-Destructive Testing and Defect Evaluation
This domain tests method selection and the interpretation of indications against acceptance criteria. You need to know what each method can and cannot find, and how defect type, orientation and location influence detection.
340 words, about 2 min07Health, Safety and Environmental Protection
This domain tests hazard recognition and control in welding operations. The exam expects specific controls, not slogans: fume extraction, radiation protection, electrical safety, fire prevention and confined-space procedure.
333 words, about 2 min08Codes, Standards and Legal/Contractual Responsibilities
This domain tests how standards and contracts allocate responsibility. The exam expects you to know which document governs what, and who must sign or approve.
327 words, about 2 min