Dimensional control is the process of measuring and verifying the accuracy of structural components to ensure they conform to design specifications. It plays a crucial role in steel structure construction by minimizing errors, ensuring proper alignment, and maintaining structural integrity.

Steel structure surveying involves the measurement, inspection, and assessment of steel frameworks in construction projects. It ensures that the structural components are installed correctly, aligned properly, and comply with design specifications and safety standards.

Metrology is the application of precision measurement techniques in surveying to ensure accurate mapping, construction, and engineering processes. It combines principles from metrology (the science of measurement) with surveying (the practice of determining positions on Earth) to achieve highly accurate spatial data.

Setting out refers to the process of transferring a design or plan onto the ground during construction projects. It involves measuring and marking key reference points and lines that guide the construction of buildings, roads, bridges, and other structures. This ensures that the construction is carried out according to the planned design, both in terms of size and location.

3D scanning in surveying is a technology-driven method for capturing high-precision, three-dimensional data of physical objects, terrains, and structures. It utilizes laser scanners, photogrammetry, or LiDAR (Light Detection and Ranging) to create accurate digital representations of real-world environments.