The type of drawings used to verify the location of structural members according to the Specification for Structural Steel Buildings are?

The correct choice is the fabricators' shop and erection drawings because these types of drawings provide detailed information about the dimensions, materials, and assembly of structural components. They illustrate how individual pieces will fit together and clarify the arrangement of members in the overall structure, ensuring compliance with the specifications outlined in the Specification for Structural Steel Buildings. These drawings are critical during the fabrication and erection phases as they guide the fabrication process and help ensure that structural members are installed correctly according to the design intent.

Fabricators' shop drawings are created before the actual construction begins and focus on how the individual components will be manufactured. Erection drawings complement this by detailing how those components will be assembled on-site, including their locations and relationships to other elements. This specificity is essential for achieving structural integrity and for meeting code compliance during the construction process.

In contrast, blueprints and engineering designs are broader and may not include the specific assembly details needed for installation verification. Architect's plans typically focus on the aesthetic aspects and may not provide the detailed specifications necessary for structural members. Erector's sketches could be informal and used on-site, but they lack the precision and formal approval associated with fabricators' shop and erection drawings, making them less reliable for the task of verifying member location.