AWS D1.1

AWS D1.1 governs the welding of steel structures — buildings, bridges and other structural steel work — covering design, workmanship, qualification and inspection requirements specific to structural applications.

It applies to steel structures within its stated thickness and material limits, using the welding processes it recognizes. Pressure equipment, piping and several other specialized categories fall outside its scope and are governed by other codes.

Structural welding differs from pressure-equipment welding in what failure risk looks like and how it is controlled — D1.1 reflects that with its own qualification, inspection and acceptance-criteria framework tailored to structural steel.

Like Section IX, D1.1 requires qualified welding procedures and qualified welders, but defines its own variables, testing methods and acceptance limits suited to structural work rather than deferring to the ASME approach.

The code sets out visual and nondestructive inspection requirements and acceptance criteria for completed structural welds, tied to the statically or cyclically loaded nature of the connection being made.

Projects sometimes reference both AWS D1.1 and ASME Section IX where structural and pressure-retaining work coexist, or apply ISO 9606-1 welder qualifications on international contracts — coordinating which standard governs which scope is a project-level decision.

This page is an original, summary-level overview prepared for orientation purposes. It is not a substitute for the official AWS D1.1/D1.1M Structural Welding Code — Steel, which should be consulted directly for any actual qualification or fabrication work.