A "useful" understanding of this code relies on its three primary functional areas:

What specific of the AWS D1.1 code does your project contract require?

For a WPS to be "prequalified," it must strictly adhere to all the limitations defined in Clause 5 of the code:

Specific rules for welding shear studs.

AWS D1.1 defines the responsibilities of inspectors and the acceptance criteria for welds. Mandatory for all welds.